In this paper a new combination Radial Basis Function Neural Network and p-q Power Theory (RBFNN-PQ) proposed to control shunt active power filters (SAPF). The recommended system has better specifications in comparison with other control methods. In the proposed combination an RBF neural network is employed to extract compensation reference current when supply voltages are distorted and/or unbalance sinusoidal. In order to make the employed model much simpler and tighter an adaptive algorithm for RBF network is proposed. The proposed RBFNN filtering algorithm is based on efficient training methods called hybrid learning method.The method requires a small size network, very robust, and the proposed algorithms are very effective. Extensive simulations are carried out with PI as well as RBFNN controller for p-q control strategies by considering different voltage conditions and adequate results were presented.
Performance Analysis Of PV Interfaced Neural Network Based Hybrid Active Powe...IJERA Editor
This paper presents a comparative analysis of neural network controlled PV interfaced hybrid active power filter designed for harmonic compensation for nonlinear load.The neural network has been chosen for reference current generation because of its fast adaptiveness, simple calculation and high accuracy to eliminate harmonics.This paper shows a novel approach to interface PV array to hybrid active power filter to keep the capacitor voltage stable. To obtain efficient output from PV Array Maximum power point tracking (MPPT) is employed in it. MPPT is able to extract maximum possible power from PV Array of change in atmospheric condition. Simulation and analysis of hybrid active power filter and PV Array is done under nonlinear load, sudden change in load and unbalanced load conditions. The detailed simulation results have been presented to validate the proposed methodology.
Convergence Problems Of Contingency Analysis In Electrical Power Transmission...CSCJournals
Contingency analysis is a tool used by power system engineers for planning and assessing
power system reliability. The conventional analytical method which is mathematical model based,
is not only tedious and time consuming in view of the large number of components in the network
but always left some critical components unassessed due to non-convergence of the power flow
analysis of such, hence the contingency analysis of such system could not be said to be
completed.
In this work, contingency analysis of line components of a standard IEEE-30 Bus and real 330-kV
Nigerian Transmission Company of Nigeria (TCN) network (28Bus) systems were investigated
using Radial Basis Function Neural Network (RBF-NN) which is artificial intelligence based.
The contingency analysis was carried out by solving the non-linear algebraic equations of steady
state model for the standard IEEE-30 Bus and TCN-28 Bus power networks using NewtonRaphson
(N-R) power flow method. RBF-NN method was used for the computation of Reactive
and Active performance indices (PIR and PIA ) which were ranked in order to reveal the criticality
of each line outage. Simulation was carried out using MATLAB R2013a version. The nonconverged
lines in both systems were reinforced and re-analysed. The results of contingency
analyses of the reinforced systems show more robust systems with complete line ranking.
The extensive use of non-linear loads in industry becomes increasingly a serious problem that affects the quality of energy delivered to customers. Therefore, the shunt active power filter (SAPF) has emerged as an important industrial tool to eliminate induced harmonic currents and compensating of reactive power. This paper proposes an improved control configuration for SAPF based on a modern technique called predictive direct power control (Predictive-DPC). The principle of this control is based on the direct regulation of the instantaneous active and reactive powers to guarantee a good energy quality on the grid side. For this purpose the appropriate average voltage vector which cancels power tracking errors is calculated by a simple predictive model at the bigining of each control period. This type of control includes various features such as the lack of look up table (LUTs) and closed current loops and the constant switching frequency is achieved through the use of PWM modulation. The results of the simulation process show a high performance in the steady and transient state function for predictive-DPC control that might be a reasonable alternative to conventional DPC in the field of active power filtering.
Artificial Intelligence Technique based Reactive Power Planning Incorporating...IDES Editor
Reactive Power Planning is a major concern in the
operation and control of power systems This paper compares
the effectiveness of Evolutionary Programming (EP) and
New Improved Differential Evolution (NIMDE) to solve
Reactive Power Planning (RPP) problem incorporating
FACTS Controllers like Static VAR Compensator (SVC),
Thyristor Controlled Series Capacitor (TCSC) and Unified
power flow controller (UPFC) considering voltage stability.
With help of Fast Voltage Stability Index (FVSI), the critical
lines and buses are identified to install the FACTS controllers.
The optimal settings of the control variables of the generator
voltages,transformer tap settings and allocation and parameter
settings of the SVC,TCSC,UPFC are considered for reactive
power planning. The test and Validation of the proposed
algorithm are conducted on IEEE 30–bus system and 72-bus
Indian system.Simulation results shows that the UPFC gives
better results than SVC and TCSC and the FACTS controllers
reduce the system losses.
A fault-tolerant photovoltaic integrated shunt active power filter with a 27-...IJECEIAES
This paper introduces a fault-tolerant shunt active power filter (SAPF). The novility in of this work is that it poposes a solutions to increase the reliability of shunt active power filter to maintain its operation under a single-phase open-circuit fault in the SAPF. This will increase the reliability of the whole power system. The SAPF is composed of a 4-leg 27-level inverter based on asymmetric cascaded H-bridge topology. If an open-circuit fault is introduced to the operation of the SAPF, a special control technique will be implemented and the redundant leg of the SAPF will be activated. The faulttolerant SAPF can do many tasks under healthy operating conditions and post and open circuit fault depending on the state of charge (SOC) of the batteries. It can mitigate harmonics in the power system, improve power factor in the system by injecting reactive power, and inject real power to the system. The proposed SAPF is tested and simulated in MATLAB/Simulink and the results have shown a significant improvement in total harmonics distortion (THD) of the source current from 13.9% to 3.9% under the normal operating condition and from 42% to 8.4% post and open circuit fault.
Neural Network based p-q-r Theory for Harmonic Reduction and Neutral Current ...IJECEIAES
The power quality compensator chosen in this paper is a DSTATCOM which integrates a three phase four leg Voltage Source Converter (VSC) with a DC capacitor. The major role of the DSTATCOM is to mitigate the components of harmonic/reactive current present in the line current thereby shapes the grid current to be sinusoidal and improves the power factor nearly unity under varying conditions. In addition DSATATCOM mitigates neutral current (I ) and balances the load currents under unbalanced conditions in three phase four wire (3P4W) distribution system. The control strategy proposed for the DSTATCOM is a Neural Network (NN) based p-q-r theory with two Artificial Neural Network (ANN) controllers for a 3P4W distribution system. The reference signal for 3P3W Shunt Active Power Filter (SAPF) is calculated by implementing an ANN controller. The alleviation of I sn under unbalanced condition is achieved by another ANN controller which produces reference signal for the 1Φ APF. The performance of the proposed DSTATCOM is analysed for various conditions through simulations in MATLAB SIMULINK and the simulation results justify the effectiveness of the propounded NN based control algorithm for DSTATCOM. sn
A Study of Load Flow Analysis Using Particle Swarm OptimizationIJERA Editor
Load flow study is done to determine the power system static states (voltage magnitudes and voltage angles) at each bus to find the steady state working condition of a power system. It is important and most frequently car-ried out study performed by power utilities for power system planning, optimization, operation and control. In this project a Particle Swarm Optimization (PSO) is proposed to solve load flow problem under different load-ing/ contingency conditions for computing bus voltage magnitudes and angles of the power system. With the increasing size of power system, this is very necessary to finding the solution to maximize the utilization of ex-isting system and to provide adequate voltage support. For this the good voltage profile is must. STATCOM, if placed optimally can be effective in providing good voltage profile and in turn resulting into stable power sys-tem. The study presents a hybrid particle swarm based methodology for solving load flow in electrical power systems. Load flow is an electrical engineering well-known problem which provides the system status in the steady-state and is required by several functions performed in power system control centers.
Performance Analysis Of PV Interfaced Neural Network Based Hybrid Active Powe...IJERA Editor
This paper presents a comparative analysis of neural network controlled PV interfaced hybrid active power filter designed for harmonic compensation for nonlinear load.The neural network has been chosen for reference current generation because of its fast adaptiveness, simple calculation and high accuracy to eliminate harmonics.This paper shows a novel approach to interface PV array to hybrid active power filter to keep the capacitor voltage stable. To obtain efficient output from PV Array Maximum power point tracking (MPPT) is employed in it. MPPT is able to extract maximum possible power from PV Array of change in atmospheric condition. Simulation and analysis of hybrid active power filter and PV Array is done under nonlinear load, sudden change in load and unbalanced load conditions. The detailed simulation results have been presented to validate the proposed methodology.
Convergence Problems Of Contingency Analysis In Electrical Power Transmission...CSCJournals
Contingency analysis is a tool used by power system engineers for planning and assessing
power system reliability. The conventional analytical method which is mathematical model based,
is not only tedious and time consuming in view of the large number of components in the network
but always left some critical components unassessed due to non-convergence of the power flow
analysis of such, hence the contingency analysis of such system could not be said to be
completed.
In this work, contingency analysis of line components of a standard IEEE-30 Bus and real 330-kV
Nigerian Transmission Company of Nigeria (TCN) network (28Bus) systems were investigated
using Radial Basis Function Neural Network (RBF-NN) which is artificial intelligence based.
The contingency analysis was carried out by solving the non-linear algebraic equations of steady
state model for the standard IEEE-30 Bus and TCN-28 Bus power networks using NewtonRaphson
(N-R) power flow method. RBF-NN method was used for the computation of Reactive
and Active performance indices (PIR and PIA ) which were ranked in order to reveal the criticality
of each line outage. Simulation was carried out using MATLAB R2013a version. The nonconverged
lines in both systems were reinforced and re-analysed. The results of contingency
analyses of the reinforced systems show more robust systems with complete line ranking.
The extensive use of non-linear loads in industry becomes increasingly a serious problem that affects the quality of energy delivered to customers. Therefore, the shunt active power filter (SAPF) has emerged as an important industrial tool to eliminate induced harmonic currents and compensating of reactive power. This paper proposes an improved control configuration for SAPF based on a modern technique called predictive direct power control (Predictive-DPC). The principle of this control is based on the direct regulation of the instantaneous active and reactive powers to guarantee a good energy quality on the grid side. For this purpose the appropriate average voltage vector which cancels power tracking errors is calculated by a simple predictive model at the bigining of each control period. This type of control includes various features such as the lack of look up table (LUTs) and closed current loops and the constant switching frequency is achieved through the use of PWM modulation. The results of the simulation process show a high performance in the steady and transient state function for predictive-DPC control that might be a reasonable alternative to conventional DPC in the field of active power filtering.
Artificial Intelligence Technique based Reactive Power Planning Incorporating...IDES Editor
Reactive Power Planning is a major concern in the
operation and control of power systems This paper compares
the effectiveness of Evolutionary Programming (EP) and
New Improved Differential Evolution (NIMDE) to solve
Reactive Power Planning (RPP) problem incorporating
FACTS Controllers like Static VAR Compensator (SVC),
Thyristor Controlled Series Capacitor (TCSC) and Unified
power flow controller (UPFC) considering voltage stability.
With help of Fast Voltage Stability Index (FVSI), the critical
lines and buses are identified to install the FACTS controllers.
The optimal settings of the control variables of the generator
voltages,transformer tap settings and allocation and parameter
settings of the SVC,TCSC,UPFC are considered for reactive
power planning. The test and Validation of the proposed
algorithm are conducted on IEEE 30–bus system and 72-bus
Indian system.Simulation results shows that the UPFC gives
better results than SVC and TCSC and the FACTS controllers
reduce the system losses.
A fault-tolerant photovoltaic integrated shunt active power filter with a 27-...IJECEIAES
This paper introduces a fault-tolerant shunt active power filter (SAPF). The novility in of this work is that it poposes a solutions to increase the reliability of shunt active power filter to maintain its operation under a single-phase open-circuit fault in the SAPF. This will increase the reliability of the whole power system. The SAPF is composed of a 4-leg 27-level inverter based on asymmetric cascaded H-bridge topology. If an open-circuit fault is introduced to the operation of the SAPF, a special control technique will be implemented and the redundant leg of the SAPF will be activated. The faulttolerant SAPF can do many tasks under healthy operating conditions and post and open circuit fault depending on the state of charge (SOC) of the batteries. It can mitigate harmonics in the power system, improve power factor in the system by injecting reactive power, and inject real power to the system. The proposed SAPF is tested and simulated in MATLAB/Simulink and the results have shown a significant improvement in total harmonics distortion (THD) of the source current from 13.9% to 3.9% under the normal operating condition and from 42% to 8.4% post and open circuit fault.
Neural Network based p-q-r Theory for Harmonic Reduction and Neutral Current ...IJECEIAES
The power quality compensator chosen in this paper is a DSTATCOM which integrates a three phase four leg Voltage Source Converter (VSC) with a DC capacitor. The major role of the DSTATCOM is to mitigate the components of harmonic/reactive current present in the line current thereby shapes the grid current to be sinusoidal and improves the power factor nearly unity under varying conditions. In addition DSATATCOM mitigates neutral current (I ) and balances the load currents under unbalanced conditions in three phase four wire (3P4W) distribution system. The control strategy proposed for the DSTATCOM is a Neural Network (NN) based p-q-r theory with two Artificial Neural Network (ANN) controllers for a 3P4W distribution system. The reference signal for 3P3W Shunt Active Power Filter (SAPF) is calculated by implementing an ANN controller. The alleviation of I sn under unbalanced condition is achieved by another ANN controller which produces reference signal for the 1Φ APF. The performance of the proposed DSTATCOM is analysed for various conditions through simulations in MATLAB SIMULINK and the simulation results justify the effectiveness of the propounded NN based control algorithm for DSTATCOM. sn
A Study of Load Flow Analysis Using Particle Swarm OptimizationIJERA Editor
Load flow study is done to determine the power system static states (voltage magnitudes and voltage angles) at each bus to find the steady state working condition of a power system. It is important and most frequently car-ried out study performed by power utilities for power system planning, optimization, operation and control. In this project a Particle Swarm Optimization (PSO) is proposed to solve load flow problem under different load-ing/ contingency conditions for computing bus voltage magnitudes and angles of the power system. With the increasing size of power system, this is very necessary to finding the solution to maximize the utilization of ex-isting system and to provide adequate voltage support. For this the good voltage profile is must. STATCOM, if placed optimally can be effective in providing good voltage profile and in turn resulting into stable power sys-tem. The study presents a hybrid particle swarm based methodology for solving load flow in electrical power systems. Load flow is an electrical engineering well-known problem which provides the system status in the steady-state and is required by several functions performed in power system control centers.
A Novel Study on Bipolar High Voltage Direct Current Transmission Lines Prote...IJECEIAES
In long dc transmission lines identification of fault is important for transferring a large amount of power. In bipolar Line commutated converter transmission lines are subjected to harsh weather condition so accurate and rapid clearance of fault is essential. A comparative study of the bipolar system with both converters healthy and one converter tripped is studied. Most of the research paper has focussed on transmission line faults in bipolar mode but none of them had focussed when HVDC system works in monopolar mode after the fault. In the proposed scheme the voltage signals are extracted from both poles of the rectifier ends and are processed to identify the faults in transmission lines.The Artificial neural network is utilised in detecting the fault in both bipolar and monopolar system. Since it can identify the relationship between input and output data to detect the fault pattern it can be utilised under all conditions. Moreover, benefits of the proposed method are its accuracy, no requirement of the communication system as it acquires data from one end and has a reach setting of 99%.
Optimal Placement of DG for Loss Reduction and Voltage Sag Mitigation in Radi...IDES Editor
This paper presents the need to operate the power
system economically and with optimum levels of voltages has
further led to an increase in interest in Distributed
Generation. In order to reduce the power losses and to improve
the voltage in the distribution system, distributed generators
(DGs) are connected to load bus. To reduce the total power
losses in the system, the most important process is to identify
the proper location for fixing and sizing of DGs. It presents a
new methodology using a new population based meta heuristic
approach namely Artificial Bee Colony algorithm(ABC) for
the placement of Distributed Generators(DG) in the radial
distribution systems to reduce the real power losses and to
improve the voltage profile, voltage sag mitigation. The power
loss reduction is important factor for utility companies because
it is directly proportional to the company benefits in a
competitive electricity market, while reaching the better power
quality standards is too important as it has vital effect on
customer orientation. In this paper an ABC algorithm is
developed to gain these goals all together. In order to evaluate
sag mitigation capability of the proposed algorithm, voltage
in voltage sensitive buses is investigated. An existing 20KV
network has been chosen as test network and results are
compared with the proposed method in the radial distribution
system.
Design and Performance Analysis of Genetic based PID-PSS with SVC in a Multi-...IDES Editor
Damping of power system oscillations with the help
of proposed optimal Proportional Integral Derivative Power
System Stabilizer (PID-PSS) and Static Var Compensator
(SVC)-based controllers are thoroughly investigated in this
paper. This study presents robust tuning of PID-PSS and
SVC-based controllers using Genetic Algorithms (GA) in
multi machine power systems by considering detailed model
of the generators (model 1.1). The effectiveness of FACTSbased
controllers in general and SVC-based controller in
particular depends upon their proper location. Modal
controllability and observability are used to locate SVC–based
controller. The performance of the proposed controllers is
compared with conventional lead-lag power system stabilizer
(CPSS) and demonstrated on 10 machines, 39 bus New England
test system. Simulation studies show that the proposed genetic
based PID-PSS with SVC based controller provides better
performance.
Line Losses in the 14-Bus Power System Network using UPFCIDES Editor
Controlling power flow in modern power systems
can be made more flexible by the use of recent developments
in power electronic and computing control technology. The
Unified Power Flow Controller (UPFC) is a Flexible AC
transmission system (FACTS) device that can control all the
three system variables namely line reactance, magnitude and
phase angle difference of voltage across the line. The UPFC
provides a promising means to control power flow in modern
power systems. Essentially the performance depends on proper
control setting achievable through a power flow analysis
program. This paper presents a reliable method to meet the
requirements by developing a Newton-Raphson based load
flow calculation through which control settings of UPFC can
be determined for the pre-specified power flow between the
lines. The proposed method keeps Newton-Raphson Load Flow
(NRLF) algorithm intact and needs (little modification in the
Jacobian matrix). A MATLAB program has been developed to
calculate the control settings of UPFC and the power flow
between the lines after the load flow is converged. Case studies
have been performed on IEEE 5-bus system and 14-bus system
to show that the proposed method is effective. These studies
indicate that the method maintains the basic NRLF properties
such as fast computational speed, high degree of accuracy and
good convergence rate.
This work presents a study of the three-phase parallel active power filter and the various controllers used in its control. Moreover, in order to improve the quality of electrical energy, by making it conform to the new normative constraints, we have also been led to develop and apply advanced automation methods. In this framework, this paper reports of several regulatory structures : fuzzy logic, PWM, new space vector PWM (NSVPWM), space vector PWM (SVPWM), HYSTERESIS moreover, in order to produce a parallel active filter, a thorough study of experimental feasibility was carried out, taking into account the industrial constraints of the product both in its design and its application.
PV Source Integrated Micro-Grid for Power Quality Improvement using MPPT Tech...Niteesh Shanbog
The demand for Electrical energy is increasing day by day as it can be easily converted to another form of energy. All consumers expect Electrical energy with high power quality. Most of the commercial and industrial loads are inductive in nature and need power electronic circuits/ controllers to get smooth control of the equipment. This, in turn, leads to the injection of harmonics into the system, hence the power quality is affected. The above problem needs to be addressed and eliminated. In this paper, a shunt active power filter is used to mitigate the harmonics. Id-Iq control is used to analyse the performance of the filter and is simulated using MATLAB software. The MPPT controller is used to improving the power quality of the system.
A Novel Distribution System Power Flow Algorithm using Forward Backward Matri...iosrjce
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This paper proposes a Wavelet based Adaptive Neuro-Fuzzy Inference System (WANFIS) applied to forecast the wind power and enhance the accuracy of one step ahead with a 10 minutes resolution of real time data collected from a wind farm in North India. The proposed method consists two cases. In the first case all the inputs of wind series and output of wind power decomposition coefficients are carried out to predict the wind power. In the second case all the inputs of wind series decomposition coefficients are carried out to get wind power prediction. The performance of proposed WANFIS is compared to Wavelet Neural Network (WNN) and the results of the proposed model are shown superior to compared methods.
CONTROL OF BATTERY OPERATED SYSTEM WITH A DC-DC BOOSTCONVERTER FED DSTATCOM U...ijiert bestjournal
This paper presents a comprehensive survey of DSTATCOM control strategies put forward recently. It is
aimed at providing a broad perspective on the status of DSTATCOM control methods to researchers and
application engineers dealing with harmonic suppression issues. Many control techniques have been
designed, developed, and realized for active filters in recent years. The proposed DSTATCOM consists of a
three-leg Voltage Source Converter (VSC) with a dc bus capacitor. The PV array or battery operated boost
converter is proposed to maintain the dc link voltage of the dc bus capacitor for continuous compensation
for the load. This paper presents to evaluate the performance comparison of two control strategies for
extracting the reference currents to control the proposed DSTATCOM. The two control methods are
Synchronous Reference Frame (SRF) theory and IcosΦ algorithm. The performance of the DSTATCOM is
validated using MATLAB software with its simulink and Power System Block set (PSB) toolboxes. The
simulation results for the two control methods are compared to validate the superior performance of the
IcosΦ algorithm.
Hysteresis Current Control Based Shunt Active Power Filter for Six Pulse Ac/D...IJERA Editor
In this paper the simulation of Shunt Active power Filter using P-Q theory and PI controller has been presented. This SAPF compensates the harmonic currents drawn by three phase six pulse AC/DC converter. The process of compensation is done by calculating the instantaneous reactive power losses using p-q theory and the PI controller to reduce the ripple voltage of the dc capacitor of the PWM-VSI. This approach is different from conventional approach and provides very effective solution. In this simulation we use hysteresis band current controller (HCC) for switching the VSI inverter. The simulation has been done for both steady state and transient conditions.
REDUCTION IN THE TRANSIENT TIME OF SHUNT ACTIVE FILTERS USING INTELLIGENT CON...ijscmc
This paper deals with the implementation of new proposed strategy for the reduction in the transient time of
shunt active filter using intelligent controllers. Intelligent control is a class of control techniques that use
various AI computing approaches like fuzzy logic, neural network, evolutionary computation, genetic
algorithm etc. The proposed strategy works on the principle of energy of the capacitor to maintain the DClink
voltage of shunt connected active filter and thus reduces the transient time whenever there is sudden
change in the load. A comparison using the PI controller, Fuzzy logic controller and Artificial neural
controller has been made using MATLAB Simulink Power System Toolbox.
An Improved Double Fuzzy PI Controller For Shunt Active Power Filter DC Bus R...IJPEDS-IAES
This paper targets to demonstrate the importance of the choice of the
algorithm references detection to be applied with a double fuzzy PI corrector
(DFPI) for the control and the regulation of a shunt active power filter
(SAPF) DC bus voltage. In a previous work, the synchronous reference
frame (SRF) algorithm was applied and gave satisfactory results. In the
present paper, the SRF is compared to the positive sequence of the
fundamental of the source voltage algorithm (PSF) which offered better
results regarding the power quality of the considered main utility feeding a
variable DC RL load throughout a diode bridge. The results were carried out
using computer simulation performed under MATLAB/Simulink
environment. To make the obtained results more convenient, a comparison
between the couples (SRF, PI), (PSF, PI), (SRF, DFPI), (PSF, DFPI) is added
to prove the effectiveness of the couple (PSF, DFPI) in satisfying the
compromise between a good regulation of the SAPF DC bus voltage and a
good quality of filtering resulting in an improved quality of power.
Performance Evaluation of GA optimized Shunt Active Power Filter for Constant...ijeei-iaes
Sinusoidal Current Control strategy for extracting reference currents for shunt active power filters have been modified using Genetic Algorithm and its performances have been compared. The acute analysis of Comparison of the compensation capability based on THD and speedwell be done, and recommendations will be given for the choice of technique to be used. The simulated results using MATLAB model are shown, and they will undoubtedly prove the importance of the proposed control technique of aircraft shunt APF.
The Green Energy sources (solar, wind) are performing a vigorous role to reach the electrical power demand. Due to the presence of non-linear loads, reactive loads in the distribution system and the injection of wind power into the grid integrated system results power quality issues like current harmonics, voltage fluctuations, reactive power demand etc. This paper mainly investigates the designing and satisfactory performance evaluation of solar farm as PV-STATCOM (Static Synchronous Compensator) for enhancement of power quality in grid tie system by using MATLAB environment (Simulink). The proportional and integral (PI) Controller and Hysteresis Current Controller (HCC) were effectively utilized to inject the desired current from voltage source converter (VSC) based PV-STATCOM at PCC for the mitigation of quality related problems in the proposed test system.
This paper presents the control for Shunt Active Power (SAPF) filter in photovoltaic (PV) systems connected to the grid. The proposed configuration of the system consists of a photovoltaic array that connected to the grid through the three-phase inverter topology that also serves as an active filter. Photovoltaic is coupled in parallel with the direct curret (DC) side of the active filter. With this configuration, can be obtained three advantages, namely the elimination of harmonic currents caused by nonlinear load, reactive power injection, and injection of active power generated photovoltaic. The p-q Theory is used to calculate the harmonic reference current to be used to control the active filter coupled fotovoltaic in generating anti-harmonic currents. The results show that system can reduce harmonic distortion from THD 27.22% to be THD 1.05%, whereas when the active power from photovoltaic injected, the THD become 2.01%. Power sharing can also be seen from this study.
Power System State Estimation - A ReviewIDES Editor
The aim of this article is to provide a comprehensive
survey on power system state estimation techniques. The
algorithms used for finding the system states under both static
and dynamic state estimations are discussed in brief. The
authors are opinion that the scope of pursuing research in the
area of state estimation with PMU and SCADA measurements
is the state of the art and timely.
Comparison of Two Compensation Control Strategies for Shunt Active Power Filt...ijtsrd
Use of nonlinear loads has been increased in large extent in industries now-a-days which injects harmonic currents in supply system. These harmonics creates power quality issue. Shunt Active Power Filter (SAPF) is the popular and efficient solution to reduce these harmonics. SAPF can overcome voltage sag, eliminate harmonics and improves power factor. SAPF reduces total harmonic distortion (THD) to acceptable level. Reference current generation is the heart of APF. Reference current generation using instantaneous reactive power (IRP) theory is presented in this paper. IRP theory is widely used to control active power filters (APFs). Modeling of this technique is implemented in MATLABsimulink. The system is experimentally implemented using DS1104 card of d SPACE system. Mr. Amit Kumar Rajan | Dr. E Vijay Kumar"Comparison of Two Compensation Control Strategies for Shunt Active Power Filter in three Systems" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, URL: http://www.ijtsrd.com/papers/ijtsrd18198.pdf http://www.ijtsrd.com/engineering/electrical-engineering/18198/comparison-of-two-compensation-control-strategies-for-shunt-active-power-filter-in-three-systems/mr-amit-kumar-rajan
Optimal Location of Multi-types of FACTS Devices using Genetic Algorithm IJORCS
The problem of improving the voltage profile and reducing power loss in electrical networks is a task that must be solved in an optimal manner. Therefore, placement of FACTS devices in suitable location can lead to control in-line flow and maintain bus voltages in desired level and reducing losses is required. This paper presents one of the heuristic methods i.e. a Genetic Algorithm to seek the optimal location of FACTS devices in a power system. Proposed algorithm is tested on IEEE 30 bus power system for optimal location of multi-type FACTS devices and results are presented.
Performance Analysis Of PV Interfaced Neural Network Based Hybrid Active Powe...IJERA Editor
This paper presents a comparative analysis of neural network controlled PV interfaced hybrid active power filter designed for harmonic compensation for nonlinear load.The neural network has been chosen for reference current generation because of its fast adaptiveness, simple calculation and high accuracy to eliminate harmonics.This paper shows a novel approach to interface PV array to hybrid active power filter to keep the capacitor voltage stable. To obtain efficient output from PV Array Maximum power point tracking (MPPT) is employed in it. MPPT is able to extract maximum possible power from PV Array of change in atmospheric condition. Simulation and analysis of hybrid active power filter and PV Array is done under nonlinear load, sudden change in load and unbalanced load conditions. The detailed simulation results have been presented to validate the proposed methodology.
Power Quality Improvement in Distribution System using ANN Based Shunt Active...IAES-IJPEDS
This paper focuses on an Artificial Neural Network (ANN) controller based Shunt Active Power Filter (SAPF) for mitigating the harmonics of the distribution system. To increase the performance of the conventional controller and take advantage of smart controllers, a feed forward-type (trained by a back propagation algorithm) ANN-based technique is implemented in shunt active power filters for producing the controlled pulses required for IGBT inverter. The proposed approach mainly work on the principle of capacitor energy to maintain the DC link voltage of a shunt connected filter and thus reduces the transient response time when there is abrupt variation in the load. The entire power system block set model of the proposed scheme has been developed in MATLAB environment. Simulations are carried out by using MATLAB, it is noticed that the %THD is reduced to 2.27% from 29.71% by ANN controlled filter. The simulated experimental results also show that the novel control method is not only easy to be computed and implemented, but also very successful in reducing harmonics.
A Novel Study on Bipolar High Voltage Direct Current Transmission Lines Prote...IJECEIAES
In long dc transmission lines identification of fault is important for transferring a large amount of power. In bipolar Line commutated converter transmission lines are subjected to harsh weather condition so accurate and rapid clearance of fault is essential. A comparative study of the bipolar system with both converters healthy and one converter tripped is studied. Most of the research paper has focussed on transmission line faults in bipolar mode but none of them had focussed when HVDC system works in monopolar mode after the fault. In the proposed scheme the voltage signals are extracted from both poles of the rectifier ends and are processed to identify the faults in transmission lines.The Artificial neural network is utilised in detecting the fault in both bipolar and monopolar system. Since it can identify the relationship between input and output data to detect the fault pattern it can be utilised under all conditions. Moreover, benefits of the proposed method are its accuracy, no requirement of the communication system as it acquires data from one end and has a reach setting of 99%.
Optimal Placement of DG for Loss Reduction and Voltage Sag Mitigation in Radi...IDES Editor
This paper presents the need to operate the power
system economically and with optimum levels of voltages has
further led to an increase in interest in Distributed
Generation. In order to reduce the power losses and to improve
the voltage in the distribution system, distributed generators
(DGs) are connected to load bus. To reduce the total power
losses in the system, the most important process is to identify
the proper location for fixing and sizing of DGs. It presents a
new methodology using a new population based meta heuristic
approach namely Artificial Bee Colony algorithm(ABC) for
the placement of Distributed Generators(DG) in the radial
distribution systems to reduce the real power losses and to
improve the voltage profile, voltage sag mitigation. The power
loss reduction is important factor for utility companies because
it is directly proportional to the company benefits in a
competitive electricity market, while reaching the better power
quality standards is too important as it has vital effect on
customer orientation. In this paper an ABC algorithm is
developed to gain these goals all together. In order to evaluate
sag mitigation capability of the proposed algorithm, voltage
in voltage sensitive buses is investigated. An existing 20KV
network has been chosen as test network and results are
compared with the proposed method in the radial distribution
system.
Design and Performance Analysis of Genetic based PID-PSS with SVC in a Multi-...IDES Editor
Damping of power system oscillations with the help
of proposed optimal Proportional Integral Derivative Power
System Stabilizer (PID-PSS) and Static Var Compensator
(SVC)-based controllers are thoroughly investigated in this
paper. This study presents robust tuning of PID-PSS and
SVC-based controllers using Genetic Algorithms (GA) in
multi machine power systems by considering detailed model
of the generators (model 1.1). The effectiveness of FACTSbased
controllers in general and SVC-based controller in
particular depends upon their proper location. Modal
controllability and observability are used to locate SVC–based
controller. The performance of the proposed controllers is
compared with conventional lead-lag power system stabilizer
(CPSS) and demonstrated on 10 machines, 39 bus New England
test system. Simulation studies show that the proposed genetic
based PID-PSS with SVC based controller provides better
performance.
Line Losses in the 14-Bus Power System Network using UPFCIDES Editor
Controlling power flow in modern power systems
can be made more flexible by the use of recent developments
in power electronic and computing control technology. The
Unified Power Flow Controller (UPFC) is a Flexible AC
transmission system (FACTS) device that can control all the
three system variables namely line reactance, magnitude and
phase angle difference of voltage across the line. The UPFC
provides a promising means to control power flow in modern
power systems. Essentially the performance depends on proper
control setting achievable through a power flow analysis
program. This paper presents a reliable method to meet the
requirements by developing a Newton-Raphson based load
flow calculation through which control settings of UPFC can
be determined for the pre-specified power flow between the
lines. The proposed method keeps Newton-Raphson Load Flow
(NRLF) algorithm intact and needs (little modification in the
Jacobian matrix). A MATLAB program has been developed to
calculate the control settings of UPFC and the power flow
between the lines after the load flow is converged. Case studies
have been performed on IEEE 5-bus system and 14-bus system
to show that the proposed method is effective. These studies
indicate that the method maintains the basic NRLF properties
such as fast computational speed, high degree of accuracy and
good convergence rate.
This work presents a study of the three-phase parallel active power filter and the various controllers used in its control. Moreover, in order to improve the quality of electrical energy, by making it conform to the new normative constraints, we have also been led to develop and apply advanced automation methods. In this framework, this paper reports of several regulatory structures : fuzzy logic, PWM, new space vector PWM (NSVPWM), space vector PWM (SVPWM), HYSTERESIS moreover, in order to produce a parallel active filter, a thorough study of experimental feasibility was carried out, taking into account the industrial constraints of the product both in its design and its application.
PV Source Integrated Micro-Grid for Power Quality Improvement using MPPT Tech...Niteesh Shanbog
The demand for Electrical energy is increasing day by day as it can be easily converted to another form of energy. All consumers expect Electrical energy with high power quality. Most of the commercial and industrial loads are inductive in nature and need power electronic circuits/ controllers to get smooth control of the equipment. This, in turn, leads to the injection of harmonics into the system, hence the power quality is affected. The above problem needs to be addressed and eliminated. In this paper, a shunt active power filter is used to mitigate the harmonics. Id-Iq control is used to analyse the performance of the filter and is simulated using MATLAB software. The MPPT controller is used to improving the power quality of the system.
A Novel Distribution System Power Flow Algorithm using Forward Backward Matri...iosrjce
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
This paper proposes a Wavelet based Adaptive Neuro-Fuzzy Inference System (WANFIS) applied to forecast the wind power and enhance the accuracy of one step ahead with a 10 minutes resolution of real time data collected from a wind farm in North India. The proposed method consists two cases. In the first case all the inputs of wind series and output of wind power decomposition coefficients are carried out to predict the wind power. In the second case all the inputs of wind series decomposition coefficients are carried out to get wind power prediction. The performance of proposed WANFIS is compared to Wavelet Neural Network (WNN) and the results of the proposed model are shown superior to compared methods.
CONTROL OF BATTERY OPERATED SYSTEM WITH A DC-DC BOOSTCONVERTER FED DSTATCOM U...ijiert bestjournal
This paper presents a comprehensive survey of DSTATCOM control strategies put forward recently. It is
aimed at providing a broad perspective on the status of DSTATCOM control methods to researchers and
application engineers dealing with harmonic suppression issues. Many control techniques have been
designed, developed, and realized for active filters in recent years. The proposed DSTATCOM consists of a
three-leg Voltage Source Converter (VSC) with a dc bus capacitor. The PV array or battery operated boost
converter is proposed to maintain the dc link voltage of the dc bus capacitor for continuous compensation
for the load. This paper presents to evaluate the performance comparison of two control strategies for
extracting the reference currents to control the proposed DSTATCOM. The two control methods are
Synchronous Reference Frame (SRF) theory and IcosΦ algorithm. The performance of the DSTATCOM is
validated using MATLAB software with its simulink and Power System Block set (PSB) toolboxes. The
simulation results for the two control methods are compared to validate the superior performance of the
IcosΦ algorithm.
Hysteresis Current Control Based Shunt Active Power Filter for Six Pulse Ac/D...IJERA Editor
In this paper the simulation of Shunt Active power Filter using P-Q theory and PI controller has been presented. This SAPF compensates the harmonic currents drawn by three phase six pulse AC/DC converter. The process of compensation is done by calculating the instantaneous reactive power losses using p-q theory and the PI controller to reduce the ripple voltage of the dc capacitor of the PWM-VSI. This approach is different from conventional approach and provides very effective solution. In this simulation we use hysteresis band current controller (HCC) for switching the VSI inverter. The simulation has been done for both steady state and transient conditions.
REDUCTION IN THE TRANSIENT TIME OF SHUNT ACTIVE FILTERS USING INTELLIGENT CON...ijscmc
This paper deals with the implementation of new proposed strategy for the reduction in the transient time of
shunt active filter using intelligent controllers. Intelligent control is a class of control techniques that use
various AI computing approaches like fuzzy logic, neural network, evolutionary computation, genetic
algorithm etc. The proposed strategy works on the principle of energy of the capacitor to maintain the DClink
voltage of shunt connected active filter and thus reduces the transient time whenever there is sudden
change in the load. A comparison using the PI controller, Fuzzy logic controller and Artificial neural
controller has been made using MATLAB Simulink Power System Toolbox.
An Improved Double Fuzzy PI Controller For Shunt Active Power Filter DC Bus R...IJPEDS-IAES
This paper targets to demonstrate the importance of the choice of the
algorithm references detection to be applied with a double fuzzy PI corrector
(DFPI) for the control and the regulation of a shunt active power filter
(SAPF) DC bus voltage. In a previous work, the synchronous reference
frame (SRF) algorithm was applied and gave satisfactory results. In the
present paper, the SRF is compared to the positive sequence of the
fundamental of the source voltage algorithm (PSF) which offered better
results regarding the power quality of the considered main utility feeding a
variable DC RL load throughout a diode bridge. The results were carried out
using computer simulation performed under MATLAB/Simulink
environment. To make the obtained results more convenient, a comparison
between the couples (SRF, PI), (PSF, PI), (SRF, DFPI), (PSF, DFPI) is added
to prove the effectiveness of the couple (PSF, DFPI) in satisfying the
compromise between a good regulation of the SAPF DC bus voltage and a
good quality of filtering resulting in an improved quality of power.
Performance Evaluation of GA optimized Shunt Active Power Filter for Constant...ijeei-iaes
Sinusoidal Current Control strategy for extracting reference currents for shunt active power filters have been modified using Genetic Algorithm and its performances have been compared. The acute analysis of Comparison of the compensation capability based on THD and speedwell be done, and recommendations will be given for the choice of technique to be used. The simulated results using MATLAB model are shown, and they will undoubtedly prove the importance of the proposed control technique of aircraft shunt APF.
The Green Energy sources (solar, wind) are performing a vigorous role to reach the electrical power demand. Due to the presence of non-linear loads, reactive loads in the distribution system and the injection of wind power into the grid integrated system results power quality issues like current harmonics, voltage fluctuations, reactive power demand etc. This paper mainly investigates the designing and satisfactory performance evaluation of solar farm as PV-STATCOM (Static Synchronous Compensator) for enhancement of power quality in grid tie system by using MATLAB environment (Simulink). The proportional and integral (PI) Controller and Hysteresis Current Controller (HCC) were effectively utilized to inject the desired current from voltage source converter (VSC) based PV-STATCOM at PCC for the mitigation of quality related problems in the proposed test system.
This paper presents the control for Shunt Active Power (SAPF) filter in photovoltaic (PV) systems connected to the grid. The proposed configuration of the system consists of a photovoltaic array that connected to the grid through the three-phase inverter topology that also serves as an active filter. Photovoltaic is coupled in parallel with the direct curret (DC) side of the active filter. With this configuration, can be obtained three advantages, namely the elimination of harmonic currents caused by nonlinear load, reactive power injection, and injection of active power generated photovoltaic. The p-q Theory is used to calculate the harmonic reference current to be used to control the active filter coupled fotovoltaic in generating anti-harmonic currents. The results show that system can reduce harmonic distortion from THD 27.22% to be THD 1.05%, whereas when the active power from photovoltaic injected, the THD become 2.01%. Power sharing can also be seen from this study.
Power System State Estimation - A ReviewIDES Editor
The aim of this article is to provide a comprehensive
survey on power system state estimation techniques. The
algorithms used for finding the system states under both static
and dynamic state estimations are discussed in brief. The
authors are opinion that the scope of pursuing research in the
area of state estimation with PMU and SCADA measurements
is the state of the art and timely.
Comparison of Two Compensation Control Strategies for Shunt Active Power Filt...ijtsrd
Use of nonlinear loads has been increased in large extent in industries now-a-days which injects harmonic currents in supply system. These harmonics creates power quality issue. Shunt Active Power Filter (SAPF) is the popular and efficient solution to reduce these harmonics. SAPF can overcome voltage sag, eliminate harmonics and improves power factor. SAPF reduces total harmonic distortion (THD) to acceptable level. Reference current generation is the heart of APF. Reference current generation using instantaneous reactive power (IRP) theory is presented in this paper. IRP theory is widely used to control active power filters (APFs). Modeling of this technique is implemented in MATLABsimulink. The system is experimentally implemented using DS1104 card of d SPACE system. Mr. Amit Kumar Rajan | Dr. E Vijay Kumar"Comparison of Two Compensation Control Strategies for Shunt Active Power Filter in three Systems" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, URL: http://www.ijtsrd.com/papers/ijtsrd18198.pdf http://www.ijtsrd.com/engineering/electrical-engineering/18198/comparison-of-two-compensation-control-strategies-for-shunt-active-power-filter-in-three-systems/mr-amit-kumar-rajan
Optimal Location of Multi-types of FACTS Devices using Genetic Algorithm IJORCS
The problem of improving the voltage profile and reducing power loss in electrical networks is a task that must be solved in an optimal manner. Therefore, placement of FACTS devices in suitable location can lead to control in-line flow and maintain bus voltages in desired level and reducing losses is required. This paper presents one of the heuristic methods i.e. a Genetic Algorithm to seek the optimal location of FACTS devices in a power system. Proposed algorithm is tested on IEEE 30 bus power system for optimal location of multi-type FACTS devices and results are presented.
Performance Analysis Of PV Interfaced Neural Network Based Hybrid Active Powe...IJERA Editor
This paper presents a comparative analysis of neural network controlled PV interfaced hybrid active power filter designed for harmonic compensation for nonlinear load.The neural network has been chosen for reference current generation because of its fast adaptiveness, simple calculation and high accuracy to eliminate harmonics.This paper shows a novel approach to interface PV array to hybrid active power filter to keep the capacitor voltage stable. To obtain efficient output from PV Array Maximum power point tracking (MPPT) is employed in it. MPPT is able to extract maximum possible power from PV Array of change in atmospheric condition. Simulation and analysis of hybrid active power filter and PV Array is done under nonlinear load, sudden change in load and unbalanced load conditions. The detailed simulation results have been presented to validate the proposed methodology.
Power Quality Improvement in Distribution System using ANN Based Shunt Active...IAES-IJPEDS
This paper focuses on an Artificial Neural Network (ANN) controller based Shunt Active Power Filter (SAPF) for mitigating the harmonics of the distribution system. To increase the performance of the conventional controller and take advantage of smart controllers, a feed forward-type (trained by a back propagation algorithm) ANN-based technique is implemented in shunt active power filters for producing the controlled pulses required for IGBT inverter. The proposed approach mainly work on the principle of capacitor energy to maintain the DC link voltage of a shunt connected filter and thus reduces the transient response time when there is abrupt variation in the load. The entire power system block set model of the proposed scheme has been developed in MATLAB environment. Simulations are carried out by using MATLAB, it is noticed that the %THD is reduced to 2.27% from 29.71% by ANN controlled filter. The simulated experimental results also show that the novel control method is not only easy to be computed and implemented, but also very successful in reducing harmonics.
Power Quality Improvement in Power System using UPFCijtsrd
Occurrence of a fault in a power system causes transients. To stabilize the system, Power System Stabilizer (PSS) and Automatic Voltage Regulator (AVR) are used. Load flow analysis is done to analyze the transients introduced in the system due to the occurrence of faults. The Flexible Alternating Current Transmission (FACTS) devices such as UPFC are becoming important in suppressing power system oscillations and improving system damping. The UPFC is a solid-state device, which can be used to control the active and reactive power. This paper considers a power system as a case study for investigating the performance of UPFC is achieving stability. By using a UPFC the oscillation introduced by the faults, the voltage deviations and speed deviations can be damped out quickly than a system without a UPFC. The effectiveness of UPFC in suppressing power system oscillation is investigated by analyzing their voltage deviations and reactive power support in this paper. A proportional integral (PI) controller has been employed for the UPFC. It is also shown that a UPFC can control independently the real and reactive power flow in a transmission line. Navneet Kaur | Gagan Deep Yadav"Power Quality Improvement in Power System using UPFC" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-1 , December 2017, URL: http://www.ijtsrd.com/papers/ijtsrd7139.pdf http://www.ijtsrd.com/engineering/electrical-engineering/7139/power-quality-improvement-in-power-system-using-upfc/navneet-kaur
Harmonic Suppression of Shunt Hybrid Filter using LQR-PSO based IJECEIAES
In linear quadratic regulator (LQR), two different weighting matrices play an important role in presenting the performance of this controller. Instead of using classic common approach, which is trial and error method, this study proposes a particle swarm optimization (PSO) algorithm to track the best solution of the weighting matrices. The proposed algorithm is tested on shunt hybrid active power filter (APF) to mitigate the harmonic contents in voltage and current signals in a nonlinear load system. The modeling work of this proposed system is simulated using MATLAB/Simulink software. From the simulation, the obtained results proved that using PSO in tuning the LQR controller produce smoother nonlinear voltage and current signals. In fact, the amount of current to be injected into network can be reduced up to 95%. Besides, less time is consumed during searching the optimum weighting matrices using the proposed approach.
Modeling & Analysis of Shunt Active Power Filter Using IRP Theory Fed to Indu...IJERA Editor
Utility distribution networks have sensitive industrial loads and critical commercial operations suffer from various types of outages and service interruptions which can cost significant financial losses. Because of sensitivity of consumers on power quality and advancement in power electronics. Active power filter technology is the most efficient way to compensate reactive power and cancel out low order harmonics generated by nonlinear loads. The shunt active power filter was considered to be the most basic configuration for the APF. This paper reviews the basic principle of shunt active power filter, along with the current tracking circuit based on the instantaneous reactive power theory and the main circuit performing as an inverter with PWM hysteresis control. The instantaneous active and reactive current component (id-iq) method and instantaneous active and reactive power (p-q) method are two control strategies which are extensively used in active filters. A shunt active filter based on the instantaneous active and reactive current component (id-iq) method is proposed. This method aims to compensate harmonic and first harmonic unbalance. A Comprehensive control method is analyzed and a harmonic Compensation simulation is conducted, the result of which verifies The harmonic detection algorithm is well-proposed and the power Quality of the grid is overall-enhanced. The results are obtained using MATLAB/SIMULINK software.
Performance Enhancement in Active Power Filter (APF) by FPGA Implementation IJECEIAES
The generated electrical power in present days is not able to meet its end-user requirement as power demand is gradually increasing and expected to be increasing more in future days. In the power quality management, the parameters/factors like harmonic currents (HC) and reactive power (RP) yields the major issues in the power distribution units causing transformer heating, line losses, and machine vibration. To overcome these issues, several control mechanisms have been presented and implemented in recent past. The control algorithm based on synchronous reference frame (SRF) offers a better response by dividing the HC and RP. But the SRF based control algorithm requires better synchronization among the utility voltage and input current. To achieve this, the existing researches have used digital signal processing (DSP) and microcontroller, but these systems fail to provide better performance as they face issues like limited sampling time, less accuracy, and high computational complexity. Thus, to enhance the performance of active power filter (APF), we present an FPGA based approach. Also, to validate the performance of the proposed approach, we have used Xilinx 14.7 and Modelsim (6.3f) simulator and compared with other previous work. From the results analysis, it is found that the approach has good performance.
This paper presents a grid-connected photovoltaic system (PV) used as a shunt active power filter (SAPF) to provide the power factor correction, harmonic elimination, reactive power compensation and to simultaneously supply power from a PV system to the utility. A direct power control (DPC) method is used for controlling the system to feed the photovoltaic energy in synchronization with grid and provide power quality improvement. The PI parameters of DC-link voltage controller are tuned using the Particle Swarm Optimization (PSO) algorithm without the need for an exact mathematical model of system. This PI-PSO controller gives better results for robustness, harmonic minimization and reduces the overshoot and undershoots of PI controller. The overall control of system is tested in Matlab/Simulink environment. Then, the simulations results demonstrate the robustness and feasibility of proposed method.
Study of the performance of fault-tolerant multi-level inverter included in s...IJECEIAES
Nowadays, the large number of shunt active power filters (SAPF) is installed in many grid networks to eliminate the source currents harmonics and enhance power quality. These filters are installed in different places according to the filtration requirements. The connection between SAPF and grid network has a negative effect during the open-circuit fault of the insulated gate bipolar transistor (IGBT) switch of the SAPF. This paper proposes the application of the new diagnostic method based on the trigonometric circle and mean value variations techniques to the early detection and precise location of the open-circuit fault of the IGBT switches, and the inclusion of the modified reconfigurable inverter topology to allow the perfect continuity of the filter currents, and improve the diagnostic of the open-circuit fault. A single-sided amplitude spectrum technique (SSAS) is applied on the source currents to get the THDi% value. The obtained simulation results prove, the great success of the proposed diagnostic method, the ability of the modified reconfigurable inverter to be adapted to the grid network, the short response time between the diagnosis and the reconfiguration process is about 7 ms which is very sufficient to guarantee the rapid continuity of the shunt active power filter.
A Technique for Shunt Active Filter meld micro grid SystemIJERA Editor
The proposed system presents a control technique for a micro grid connected hybrid generation system ith case study interfaced with a three phase shunt active filter to suppress the current harmonics and reactive power present in the load using PQ Theory with ANN controller. This Hybrid Micro Grid is developed using freely renewable energy resources like Solar Photovoltaic (SPV) and Wind Energy (WE). To extract the maximum available power from PV panels and wind turbines, Maximum power point Tracker (MPPT) has been included. This MPPT uses the “Standard Perturbs and Observe” technique. By using PQ Theory with ANN Controller, the Reference currents are generated which are to be injected by Shunt active power filter (SAPF)to compensate the current harmonics in the non linear load. Simulation studies shows that the proposed control technique performs non-linear load current harmonic compensation maintaining the load current in phase with the source voltage.
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Power electronics play a significant role in different areas of technology, more usage of power electronic devices lead to more harmonic content and various power quality issues in the system. Therefore, power quality gains more significance in the current era of research. Power electronics equipment’s with non-linear loads concludes with more harmonic disturbances and lower power factor. Harmonic impurities are the major problem ingredient due to the connection of non-linear load. To lessen the harmonics usually passive filters are used. The major objective of this work is to monitor and analyse the power quality of uninterrupted power supply by means of DAQ system that gathers real time data on the system and then the data is analysed using National Instruments LabVIEW. Once power quality analysis is done, a new technique of filter implementation using output transformer of the UPS was explored and passive filter was simulated using MATLAB/Simulink and then simulated filter was implemented in order to achieve power quality improvement.
Comparison of Soft Computing Techniques applied in High Frequency Aircraft Sy...ijeei-iaes
Sinusoidal Current Control strategy for extracting reference currents for shunt active power filters have been optimized using Fuzzy Logic control and Adaptive Tabu search Algorithm and their performances have been compared. The acute analysis of Comparison of the compensation capability based on THD and speedwell be done, and recommendations will be given for the choice of technique to be used. The simulated results using MATLAB model are shown, and they will undoubtedly prove the importance of the proposed control technique of aircraft shunt APF.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Similar to Shunt Active Filter Based on Radial Basis Function Neural Network and p-q Power Theory (20)
The aim of this research is the speed tracking of the permanent magnet synchronous motor (PMSM) using an intelligent Neural-Network based adapative backstepping control. First, the model of PMSM in the Park synchronous frame is derived. Then, the PMSM speed regulation is investigated using the classical method utilizing the field oriented control theory. Thereafter, a robust nonlinear controller employing an adaptive backstepping strategy is investigated in order to achieve a good performance tracking objective under motor parameters changing and external load torque application. In the final step, a neural network estimator is integrated with the adaptive controller to estimate the motor parameters values and the load disturbance value for enhancing the effectiveness of the adaptive backstepping controller. The robsutness of the presented control algorithm is demonstrated using simulation tests. The obtained results clearly demonstrate that the presented NN-adaptive control algorithm can provide good trackingperformances for the speed trackingin the presence of motor parameter variation and load application.
This paper presents a fast and accurate fault detection, classification and direction discrimination algorithm of transmission lines using one-dimensional convolutional neural networks (1D-CNNs) that have ingrained adaptive model to avoid the feature extraction difficulties and fault classification into one learning algorithm. A proposed algorithm is directly usable with raw data and this deletes the need of a discrete feature extraction method resulting in more effective protective system. The proposed approach based on the three-phase voltages and currents signals of one end at the relay location in the transmission line system are taken as input to the proposed 1D-CNN algorithm. A 132kV power transmission line is simulated by Matlab simulink to prepare the training and testing data for the proposed 1D- CNN algorithm. The testing accuracy of the proposed algorithm is compared with other two conventional methods which are neural network and fuzzy neural network. The results of test explain that the new proposed detection system is efficient and fast for classifying and direction discrimination of fault in transmission line with high accuracy as compared with other conventional methods under various conditions of faults.
Among the most widespread renewable energy sources is solar energy; Solar panels offer a green, clean, and environmentally friendly source of energy. In the presence of several advantages of the use of photovoltaic systems, the random operation of the photovoltaic generator presents a great challenge, in the presence of a critical load. Among the most used solutions to overcome this problem is the combination of solar panels with generators or with the public grid or both. In this paper, an energy management strategy is proposed with a safety aspect by using artificial neural networks (ANNs), in order to ensure a continuous supply of electricity to consumers with a maximum solicitation of renewable energy.
In this paper, the artificial neural network (ANN) has been utilized for rotating machinery faults detection and classification. First, experiments were performed to measure the lateral vibration signals of laboratory test rigs for rotor-disk-blade when the blades are defective. A rotor-disk-blade system with 6 regular blades and 5 blades with various defects was constructed. Second, the ANN was applied to classify the different x- and y-axis lateral vibrations due to different blade faults. The results based on training and testing with different data samples of the fault types indicate that the ANN is robust and can effectively identify and distinguish different blade faults caused by lateral vibrations in a rotor. As compared to the literature, the present paper presents a novel work of identifying and classifying various rotating blade faults commonly encountered in rotating machines using ANN. Experimental data of lateral vibrations of the rotor-disk-blade system in both x- and y-directions are used for the training and testing of the network.
This paper focuses on the artificial bee colony (ABC) algorithm, which is a nonlinear optimization problem. is proposed to find the optimal power flow (OPF). To solve this problem, we will apply the ABC algorithm to a power system incorporating wind power. The proposed approach is applied on a standard IEEE-30 system with wind farms located on different buses and with different penetration levels to show the impact of wind farms on the system in order to obtain the optimal settings of control variables of the OPF problem. Based on technical results obtained, the ABC algorithm is shown to achieve a lower cost and losses than the other methods applied, while incorporating wind power into the system, high performance would be gained.
The significance of the solar energy is to intensify the effectiveness of the Solar Panel with the use of a primordial solar tracking system. Here we propounded a solar positioning system with the use of the global positioning system (GPS) , artificial neural network (ANN) and image processing (IP) . The azimuth angle of the sun is evaluated using GPS which provide latitude, date, longitude and time. The image processing used to find sun image through which centroid of sun is calculated and finally by comparing the centroid of sun with GPS quadrate to achieve optimum tracking point. Weather conditions and situation observed through AI decision making with the help of IP algorithms. The presented advance adaptation is analyzed and established via experimental effects which might be made available on the memory of the cloud carrier for systematization. The proposed system improve power gain by 59.21% and 10.32% compare to stable system (SS) and two-axis solar following system (TASF) respectively. The reduced tracking error of IoT based Two-axis solar following system (IoT-TASF) reduces their azimuth angle error by 0.20 degree.
Kosovo has limited renewable energy resources and its power generation sector is based on fossil fuels. Such a situation emphasizes the importance of active research and efficient use of renewable energy potential. According to the analysis of meteorological data for Kosovo, it can be concluded that among the most attractive potential wind power sites are the locations known as Kitka (42° 29' 41" N and 21° 36' 45" E) and Koznica (42° 39′ 32″ N, 21° 22′30″E). The two terrains in which the analysis was carried out are mountain areas, with altitudes of 1142 m (Kitka) and 1230 m (Koznica). the same measuring height, about 84 m above the ground, is obtained for these average wind speeds: Kitka 6,667 m/s and Koznica 6,16 m/s. Since the difference in wind speed is quite large versus a difference in altitude that is not being very large, analyses are made regarding the terrain characteristics including the terrain relief features. In this paper it will be studied how much the roughness of the terrain influences the output energy. Also, that the assumption to be taken the same as to how much they will affect the annual energy produced.
Large-scale grid-tied photovoltaic (PV) station are increasing rapidly. However, this large penetration of PV system creates frequency fluctuation in the grid due to the intermittency of solar irradiance. Therefore, in this paper, a robust droop control mechanism of the battery energy storage system (BESS) is developed in order to damp the frequency fluctuation of the multi-machine grid system due to variable active power injected from the PV panel. The proposed droop control strategy incorporates frequency error signal and dead-band for effective minimization of frequency fluctuation. The BESS system is used to consume/inject an effective amount of active power based upon the frequency oscillation of the grid system. The simulation analysis is carried out using PSCAD/EMTDC software to prove the effectiveness of the proposed droop control-based BESS system. The simulation result implies that the proposed scheme can efficiently curtail the frequency oscillation.
This study investigates experimentally the performance of two-dimensional solar tracking systems with reflector using commercial silicon based photovoltaic module, with open and closed loop control systems. Different reflector materials were also investigated. The experiments were performed at the Hashemite University campus in Zarqa at a latitude of 32⁰, in February and March. Photovoltaic output power and performance were analyzed. It was found that the modified photovoltaic module with mirror reflector generated the highest value of power, while the temperature reached a maximum value of 53 ̊ C. The modified module suggested in this study produced 5% more PV power than the two-dimensional solar tracking systems without reflector and produced 12.5% more PV power than the fixed PV module with 26⁰ tilt angle.
This paper focuses on the modeling and control of a wind energy conversion chain using a permanent magnet synchronous machine. This system behaves a turbine, a generator, DC/DC and DC/AC power converters. These are connected on both sides to the DC bus, where the inverter is followed by a filter which is connected to the grid. In this paper, we have been used two types of controllers. For the stator side converter, we consider the Takagi-Sugeno approach where the parameters of controller have been computed by the theory of linear matrix inequalities. The stability synthesis has been checked using the Lyapunov theory. According to the grid side converter, the proportional integral controller is exploited to keep a constant voltage on the DC bus and control both types of powers. The simulation results demonstrate the robustness of the approach used.
The development of modeling wind speed plays a very important in helping to obtain the actual wind speed data for the benefit of the power plant planning in the future. The wind speed in this paper is obtained from a PCE-FWS 20 type measuring instrument with a duration of 30 minutes which is accumulated into monthly data for one year (2019). Despite the many wind speed modeling that has been done by researchers. Modeling wind speeds proposed in this study were obtained from the modified Rayleigh distribution. In this study, the Rayleigh scale factor (Cr) and modified Rayleigh scale factor (Cm) were calculated. The observed wind speed is compared with the predicted wind characteristics. The data fit test used correlation coefficient (R2), root means square error (RMSE), and mean absolute percentage error (MAPE). The results of the proposed modified Rayleigh model provide very good results for users.
This paper deals with an advanced design for a pump powered by solar energyto supply agricultural lands with water and also the maximum power point is used to extract the maximum value of the energy available inside the solar panels and comparing between techniques MPPT such as Incremental conductance, perturb & observe, fractional short current circuit, and fractional open voltage circuit to find the best technique among these. The solar system is designed with main parts: photovoltaic (PV) panel, direct current/direct current (DC/DC) converter, inverter, filter, and in addition, the battery is used to save energy in the event that there is an increased demand for energy and not to provide solar radiation, as well as saving energy in the case of generation more than demand. This work was done using the matrix laboratory (MATLAB) simulink program.
The objective of this paper is to provide an overview of the current state of renewable energy resources in Bangladesh, as well as to examine various forms of renewable energies in order to gain a comprehensive understanding of how to address Bangladesh's power crisis issues in a sustainable manner. Electricity is currently the most useful kind of energy in Bangladesh. It has a substantial influence on a country's socioeconomic standing and living standards. Maintaining a stable source of energy at a cost that is affordable to everyone has been a constant battle for decades. Bangladesh is blessed with a wealth of natural resources. Bangladesh has a huge opportunity to accelerate its economic development while increasing energy access, livelihoods, and health for millions of people in a sustainable way due to the renewable energy system.
When the irradiance distribution over the photovoltaic panels is uniform, the pursuit of the maximum power point is not reached, which has allowed several researchers to use traditional MPPT techniques to solve this problem Among these techniques a PSO algorithm is used to have the maximum global power point (GMPPT) under partial shading. On the other hand, this one is not reliable vis-à-vis the pursuit of the MPPT. Therefore, in this paper we have treated another technique based on a new modified PSO algorithm so that the power can reach its maximum point. The PSO algorithm is based on the heuristic method which guarantees not only the obtaining of MPPT but also the simplicity of control and less expensive of the system. The results are obtained using MATLAB show that the proposed modified PSO algorithm performs better than conventional PSO and is robust to different partial shading models.
A stable operation of wind turbines connected to the grid is an essential requirement to ensure the reliability and stability of the power system. To achieve such operational objective, installing static synchronous compensator static synchronous compensator (STATCOM) as a main compensation device guarantees the voltage stability enhancement of the wind farm connected to distribution network at different operating scenarios. STATCOM either supplies or absorbs reactive power in order to ensure the voltage profile within the standard-margins and to avoid turbine tripping, accordingly. This paper present new study that investigates the most suitable-location to install STATCOM in a distribution system connected wind farm to maintain the voltage-levels within the stability margins. For a large-scale squirrel cage induction generator squirrel-cage induction generator (SCIG-based) wind turbine system, the impact of STATCOM installation was tested in different places and voltage-levels in the distribution system. The proposed method effectiveness in enhancing the voltage profile and balancing the reactive power is validated, the results were repeated for different scenarios of expected contingencies. The voltage profile, power flow, and reactive power balance of the distribution system are observed using MATLAB/Simulink software.
The electrical and environmental parameters of polymer solar cells (PSC) provide important information on their performance. In the present article we study the influence of temperature on the voltage-current (I-V) characteristic at different temperatures from 10 °C to 90 °C, and important parameters like bandgap energy Eg, and the energy conversion efficiency η. The one-diode electrical model, normally used for semiconductor cells, has been tested and validated for the polemeral junction. The PSC used in our study are formed by the poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). Our technique is based on the combination of two steps; the first use the Least Mean Squares (LMS) method while the second use the Newton-Raphson algorithm. The found results are compared to other recently published works, they show that the developed approach is very accurate. This precision is proved by the minimal values of statistical errors (RMSE) and the good agreement between both the experimental data and the I-V simulated curves. The obtained results show a clear and a monotonic dependence of the cell efficiency on the studied parameters.
The inverter is the principal part of the photovoltaic (PV) systems that assures the direct current/alternating current (DC/AC) conversion (PV array is connected directly to an inverter that converts the DC energy produced by the PV array into AC energy that is directly connected to the electric utility). In this paper, we present a simple method for detecting faults that occurred during the operation of the inverter. These types of faults or faults affect the efficiency and cost-effectiveness of the photovoltaic system, especially the inverter, which is the main component responsible for the conversion. Hence, we have shown first the faults obtained in the case of the short circuit. Second, the open circuit failure is studied. The results demonstrate the efficacy of the proposed method. Good monitoring and detection of faults in the inverter can increase the system's reliability and decrease the undesirable faults that appeared in the PV system. The system behavior is tested under variable parameters and conditions using MATLAB/Simulink.
The electrical distribution network is undergoing tremendous modifications with the introduction of distributed generation technologies which have led to an increase in fault current levels in the distribution network. Fault current limiters have been developed as a promising technology to limit fault current levels in power systems. Though, quite a number of fault current limiters have been developed; the most common are the superconducting fault current limiters, solid-state fault current limiters, and saturated core fault current limiters. These fault current limiters present potential fault current limiting solutions in power systems. Nevertheless, they encounter various challenges hindering their deployment and commercialization. This research aimed at designing a bridge-type nonsuperconducting fault current limiter with a novel topology for distribution network applications. The proposed bridge-type nonsuperconducting fault current limiter was designed and simulated using PSCAD/EMTDC. Simulation results showed the effectiveness of the proposed design in fault current limiting, voltage sag compensation during fault conditions, and its ability not to affect the load voltage and current during normal conditions as well as in suppressing the source powers during fault conditions. Simulation results also showed very minimal power loss by the fault current limiter during normal conditions.
This paper provides a new approach to reducing high-order harmonics in 400 Hz inverter using a three-level neutral-point clamped (NPC) converter. A voltage control loop using the harmonic compensation combined with NPC clamping diode control technology. The capacitor voltage imbalance also causes harmonics in the output voltage. For 400 Hz inverter, maintain a balanced voltage between the two input (direct current) (DC) capacitors is difficult because the pulse width modulation (PWM) modulation frequency ratio is low compared to the frequency of the output voltage. A method of determining the current flowing into the capacitor to control the voltage on the two balanced capacitors to ensure fast response reversal is also given in this paper. The combination of a high-harmonic resonator controller and a neutral-point voltage controller working together on the 400 Hz NPC inverter structure is given in this paper.
Direct current (DC) electronic load is a useful equipment for testing the electrical system. It can emulate various load at a high rating. The electronic load requires a power converter to operate and a linear regulator is a common option. Nonetheless, it is hard to control due to the temperature variation. This paper proposed a DC electronic load using the boost converter. The proposed electronic load operates in the continuous current mode and control using the integral controller. The electronic load using the boost converter is compared with the electronic load using the linear regulator. The results show that the boost converter able to operate as an electronic load with an error lower than 0.5% and response time lower than 13 ms.
More from International Journal of Power Electronics and Drive Systems (20)
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
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fast Fourier transform (FFT) and wavelet transform (WT)) [4]-[8]. There are three main techniques for
extracting harmonics; (i) frequency domain, (ii) time domain, and (iii) artificial intelligence neural networks
techniques.Some drawbacks of using frequency domain techniques are leakage problems, the
synchronization between the sampling frequency and the fundamental frequency, the larger memory needed,
large number of computations, poor performance during transient, and the filters are not real time. With time
domain filters there is a tradeoff between the attenuation and phase delay (higher the attenuation, the lower
the phase delay and vice versa), and faster transition time can cause oscillations. The artificial intelligent
techniques overcome some of the disadvantages of non-parametric methods. The three main methods used in
artificial intelligence techniques are (i) adaptive linear neuron (ADALINE), (ii) the popular back propagation
neural networks (BPNN), and (iii) radial function basis neural networks (RBFNN) [9]-[14]. The ADALINE
is used as an online harmonics identifier, and its performance depends on the number of harmonics included
in its structure. The convergence of the ADALINE slows as the number of harmonics included increases and
also subjected to fall in local minima [9]-[12]. The BPNN on the other hand deals with harmonics detection
problem as a pattern recognition problem. It uses offline supervised training to identify selected harmonics.
The long training time required in BPNN and the chance of falling in local minima is always present [9]-[12].
The RBFNN has several advantages over ADALINE and BPNN; capable of approximating highly nonlinear
functions, its structural nature facilitates the training process because the training can be done in a sequential
manner, and the use of local approximation can give better generalization capabilities [11, 13,15].
In this paper, RBFNN is used to extract the total harmonics based on p-q theory [6,11, 13,15]. The
RBFNN training technique was based on separated and sequential method. The centers of the RBFNN are
selected based on K-means clustering method, and the weights of the networks were found based on the
direct inversion method.
Instantaneous active and reactive theory (p-q theory) was introduced by H. Akagi, Kawakawa, and
Nabae in 1984 [3]. Since then, many scientists and engineers made significant contributions to its
modifications in three-phase four-wire circuits and its applications to power electronic equipment. The p-q
theory [3] based on a set of instantaneous powers defined in the time domain. No restrictions are imposed on
the voltage and current waveforms, and it can be applied to three phase systems with or without neutral wire
for three phase generic voltage and current waveforms. Thus, it is valid not only in the steady state, but also
in the transient state.
The PI controller [5]-[7] requires precise linear mathematical models, which are difficult to obtain
and may not give satisfactory performance under parameter variations, load disturbance etc.The p-q control
strategy is unable to yield an adequate solution when source voltages are not ideal. PI controller fails to
respond quickly because of the non-linear nature of the system, so we are developing artificial intelligent
techniques to analyze the performance of the system under the distorted condition.
2. INSTANTANEOUS ACTIVE AND REACTIVE POWER ( ) METHOD
The control block diagram for entire scheme is depicted in Figure 1.
Figure 1. Control block diagram for scheme
p
q
p0
ica*
icb*
icc*
icn*
ic*
ic*
PI
controller
-1
Vdc
Vdc*
ic0*
i0
∆Vdc Ploss
p
p0
vsa
vsb
vsc
iLa
iLb
iLc
+
_
a–b–c
––0 p–q–p0
Instantaneous
powers
calculation
–
Current
reference
calculation
a–b–c–n
Current
reference
calculation
a–b–c
––0
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The instantaneous load currents in three phases ( ) and source voltages in three phases( )
are tracked using sensors, followed by a coordinate transformation from to as follows.
[ ] √
[
√ √ √
√ √
]
[ ] ( )
[ ] √
[
√ √ √
√ √
]
[ ] ( )
The instantaneous values of active power ( ), reactive power ( ) and zero-sequence power ( ) are
calculated by multiplying the instantaneous components of currents and voltages as per (3). Each
of these powers has an oscillating/AC component and an average/DC component as shown in (4), (5) and (6).
[ ] √ [ ] [ ] ( )
̅ ̃ ( )
̅ ̃ ( )
̅̅̅ ̃ ( )
Here, ̅, ̅ and ̅̅̅ are AC components of , and respectively. Similarly, ̃, ̃ and ̃ represent
corresponding DC components.For reactive power and harmonic compensation, the entire reactive power ( )
and oscillating component of active power (̃) are utilized for calculation of reference filter currents in
coordinates using (7).
[ ]
√
[ ] [
̃ ̅
] ( )
The additional average power required to compensate for the losses occurring inside VSI due to the switching
of semiconductor devices is given by (8).
̅ ̅̅̅ ̅̅̅̅̅̅ ( )
Here, ̅̅̅ is the power required to maintain energy balance inside VSI. Whereas, ̅̅̅̅̅̅ is the average loss
occurring inside VSI,which is obtained from DC-link voltage regulator as per (9).
̅̅̅̅̅̅ ∫ ( )
Finally, reference filter currents in the four wires of VSI can be obtained by following (10) and (11).
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[ ] √
[
√
√
√
√
√
]
[ ] ( )
( )
3. MODIFIED METHOD
This scheme uses voltage harmonic filtering in order to make the source voltage sinusoidal; before
utilizing the same for calculation of instantaneous active and reactive powers. Control block diagram for the
entire method of reference current generation using modified scheme is illustrated in Figure 2.
Figure 2. Control block diagram for modified scheme
[ ] √ [ ]
[
√ √
]
[ ] ( )
[ ] [ ] [
̅̅̅
̅̅̅] ( )
This is followed by the same procedure of reference compensation current extraction as done in case of
conventional method.
4. RADIAL BASIS FUNCTION NETWORK
4.1. Structure of RBFNN
RBF is a new method of designing a neural network as a curve fitting problem in a high dimensional
space. According to this, learning is equivalent to find a surface in a multidimensional space that provides a
best fit to the training data. The motivation behind RBF is to interpolate the test data in a multidimensional
space.In a neural network the hidden units provides a set of functions that constitute an arbitrary „basis‟ for
the input pattern when they are expanded into the hidden space. These functions are called Radial basis
function (RBF).
The construction of RBF involves three layers with entirely different role, one input layer source
nodes with inputs I1, I2 , … , IN), one hidden layer has K neurons, and one output layer (with outputs y1, y2,
…, ym). The input-output mapping consists of two different transformations; nonlinear transformation from
p
q
ica*
icb*
icc*
icn*
ic*
ic*
PI
controller
-1
Vdc
Vdc*
ic0*
i0
∆Vdc Ploss
p
iLa
iLb
iLc
+
_
a–b–c
––0
d–q
–
p–q
Instant.
powers
calculation
–
Current
reference
calculation
a–b–c–n
Current
reference
calculation
vsa
vsb
vsc
vd
vq
vd
vq
a–b–c
d–q
Modificationtop-q scheme
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the input layer to the hidden layer and linear transformation between hidden and output layers. The
connection between the input and hidden layers is called centers and the connection between the hidden and
output layers is called weights.The overall response of the RBF network is
∑ (‖ ‖ ) (14)
here „n‟ is the number of computing units „c‟ is the RBF center, is the width of the units and „w‟ is the
weight. All widths have same value. The basis functions are usually selected as Gaussian. Although other
choices could be made for the basis function Gaussians are almost always used as they enjoy several
desirable properties from point of view of interpolation and regularization theory.
Figure 3. Basic structure for an adaptive RBF network
For RBF network determining the number and location of center is a difficult part of design.
Clustering techniques are commonly used to reduce the number of centers to a single point. Whether the RBF
network can realize optimal solution depends crucially on whether the centers can be positioned correctly or
not.During the training period the position of each RBF center is defined by the transmission of known data
sequence. The center position can be approximated as closely as desired by clustering or averaging the
centers found during several repetitions.
4.2. Learning Algorithm
The unit centers should be placed in those regions of the input space where data is present.
Unfortunately, this means that as the input vector dimension grows the number of required units‟ increases
very rapidly. Another reason for using a large number of local units before linear combination is given by
Cover‟s separatebility theorem, which states that in general, a complex pattern classification problem cast in
high dimensional space none linearly is more likely to be linearly separable then in low dimensional space.
This increase in the number of units is the price to be paid for a structure whose weight can be trained much
faster than in conventional the multilayer neural network.
The RBF learning algorithm is usually decoupled in two steps. First clustering is performed on the
input vectors to determine the unit centers and radij and then output weights are adjusted [11, 13, 15]. The
first step is accomplished using an unsupervised clustering algorithm and radij are chosen with k-nearest
neighbor heuristic. Then keeping the center and radij fixed the weights are computed in closed form using
desired output. The weights matrix w is given by
W= (15)
Where D is the desired output vector for l training data samples set. The summation of the outputs of the
RBFNN model is equal to the reference signal R(k). In this case the error E(k) equal to zero and no change in
the RBFNN weight
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( ) ( ) * ( ) ( ) (k)} (16)
The error E(k) is used to update the weights vectors based on the least-mean- square-error algorithm.
( ) ( ) (17)
( ) ( ) (18)
where ηj is the regulation factor for the jth output node.The weights updating will continue until the error
E(k) become zero again.
5. METHODOLOGY
5.1. RBFN For p-q Theory
The three phase source voltages and load currents are sampled and used to calculate the
instantaneous active power p and imaginary power q based on p-q theory. Clark transformation is used to
transform the voltages and currents from a-b-c domain to α-β domain as shown in (1) and (2). The p and q
are calculated from α-β domain voltages and currents as shown in (3). The reference current in α-β domain
can be calculated as shown in (7) and then the reference current in a-b-c domain can be calculated as shown
in (11).
5.2. Building the Delay Buffer
Instantaneous active power Sampled at constant rate and passed through the first input first output
(FIFO) buffer to create a delayed vector with length N which match the length of the input vector of RBFNN.
At any instant the FIFO buffer will contain N data samples. The training data samples for l training data
samples is written in matrix form and given by
11 12 1
21 22 2
1 2
1 2
....
....
.... . . ....
. . ....
....
l
l
l
N N Nl
p p p
p p p
X x x x
p p p
(19)
5.3. Finding the Desired Output
For each xj fast Fourier transform (FFT) is used to find the constant (DC) part of the active power
(which represents the power due to the fundamental components). The constant part obtained from applying
the FFT on x’s data become the desired output mentioned in [10] and given as equation (20). since the
number of the output nodes is one only the DC component of FFT is taken which is a scalar quantity.
FFT{ }= (20)
5.4. Training Data Generation
For the Extraction of sequence currents, the inputs are the three phase current and the corresponding
outputs. The required inputs and outputs are generated in MATLAB program. In the program the input
currents are initialized to zero, and incremented in steps. By taking one thousand samples in a cycle and
arranging them in a vector of three rows, outputs arranged in required vector size depends on the number of
the outputs. The input vector size and output vector size must have the same number of columns. The training
data is generated for ideal and distorted conditions.
The training of the network was done with MATLAB program. First clustering was performed on
the input vectors to determine the unit centers and radii and then output weights are adjusted. This was
accomplished using unsupervised clustering algorithm and radij are chosen with K-nearest neighbor
heuristic. Then, keeping the center and radij fixed the weights are computed in closed form using the desired
output. The training was done for both ideal and distorted source voltage conditions. After training the
network was simulated with trained inputs, If the network errors are within the predefined range, then the
architecture is suitable, otherwise the network architecture must be changed. After training the architecture is
converted to simulink block.
7. IJPEDS ISSN: 2088-8694
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673
6. SIMULATION RESULTS AND DISCUSSION
Extensive investigations are carried out by performing simulations in order to find out the
effectiveness of the three discussed APF control schemes. System configuration of shunt APF along with
three-phase and single-phase nonlinear diode rectifier loads is depicted in Figure 4.
Figure 4. Three-phase four-wire APF system configuration with nonlinear loads
The values of system parameters used for simulation are indicated in Table 1. Demonstration is
done under two different conditions of supply voltage. For ideal supply, completely balanced and sinusoidal
voltage of RMS is considered. Distorted supply condition is created by incorporating 3rd harmonic
component into the supply voltage.
Table 1. Values of system parameters used in simulation
Parameter Notation Value
Supply frequency
Source impedance ( ) ( )
Load-1 parameters ( ),( ) ( ) ( )
Load-2 parameters ( ),( ) ( ) ( )
Load-3 parameters
( ),
( )
( )
( )
DC-link capacitance
Reference DC-link voltage
AC-side filter parameters ( ),( ) ( ) ( )
Initially, only Load-1 is put into operation until ,to evaluate the harmonic compensation
capability. Performance under dynamic conditions is observed by sudden switching on of Load-2 and 3 at
for compensation of current harmonics, neutral current and unbalanced source current resulted due
to the single-phase load (Load-3).
Simulation results for APF employing , modified and RBFNN-PQ control schemes
under ideal supply voltage condition are shown in Figures 5. The supply voltage ( ), load current ( ),
compensation currents in phases , and ( ), neutral current ( ) and source current ( )
waveforms are presented in top to bottom order. The nature of source current before compensation is exactly
same as the load current. Neutral current, that is the current flowing in neutral conductor comes into
significance only during the time unbalance in load current exists, that is from to .
The current harmonics, neutral current and unbalance have been successfully cancelled with all the three
control methods.
Simulation results for APF employing , modified and RBFNN-PQ control schemes
under distorted supply voltage condition are shown in Figure 6. It depicts the supply voltage ( ), load
current ( ), compensation currents in phases , and ( ), neutral current ( ) and source current
isa
isb
isc
iLa
iLb
iLc
Rs
ica
icb
icc
Rc
RL1
4-Leg
VSI
Cdc
Vdc
Switchingsignals
Ls
LL1
Lc
a
b
c
+
_
Rdc1
Ldc1
RL2 LL2
a
b
c
+
_
Rdc2
Ldc2
Load-1
Load-2
Supply
RL3
c
n
+
_
Rdc3
Ldc3
Load-3
LL3
Cdc1
icn
RF
CF
a b c
isn
iLn
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674
( ) waveforms in top to bottom order. Current harmonics, neutral current and unbalance in source current
have been compensated employing all the discussed control schemes.
FFT analysis is performed in order to figure out the overall THD in the three phases of source
current under all the two supply conditions, before and after compensation with the three control schemes.
The source current THDs without and with APF employing , modified and RBFNN-PQ control
schemes under ideal and distorted supply conditions are clearly presented in Table.2 and Table.3
respectively.
(a) (b) (c)
Figure 5. Ideal supply. Supply voltage ( ), load current ( ), compensation currents in phases , and
( ), neutral current ( ) and source current ( ) waveforms under ideal supply condition for APF
employing: (a) control scheme (b) modified control scheme (c) RBFNN-PQ control scheme
(a) (b) (c)
Figure 6. Distorted supply. Supply voltage ( ), load current ( ), compensation currents in phases , and
( ), neutral current ( ) and source current ( ) waveforms under distorted supply condition for
APF employing: (a) control scheme (b) modified control scheme (c) RBFNN-PQ control scheme
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-300
0
300
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-50
0
50
time (sec)
V
s
(Volts)
i
L
(Amp)
i
ca
(Amp)
i
cb
(Amp)
i
cc
(Amp)
i
n
(Amp)
i
s
(Amp)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-60
0
60
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0
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time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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300
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0
50
time (sec)
V
s
(Volts)
i
L
(Amp)
i
ca
(Amp)
i
cb
(Amp)
i
cc
(Amp)
i
n
(Amp)
i
s
(Amp)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-60
0
60
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-25
0
25
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-300
0
300
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-50
0
50
time (sec)
V
s
(Volts)
i
L
(Amp)
i
ca
(Amp)
i
cb
(Amp)
i
cc
(Amp)
i
n
(Amp)
i
s
(Amp)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-60
0
60
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-25
0
25
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-300
0
300
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-50
0
50
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-25
0
25
time (sec)
V
s
(Volts)
i
L
(Amp)
i
ca
(Amp)
i
cb
(Amp)
i
cc
(Amp)
i
n
(Amp)
i
s
(Amp)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-60
0
60
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-300
0
300
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-50
0
50
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-25
0
25
time (sec)
V
s
(Volts)
i
L
(Amp)
i
ca
(Amp)
i
cb
(Amp)
i
cc
(Amp)
i
n
(Amp)
i
s
(Amp)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-60
0
60
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-300
0
300
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-50
0
50
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-25
0
25
time (sec)
V
s
(Volts)
i
L
(Amp)
i
ca
(Amp)
i
cb
(Amp)
i
cc
(Amp)
i
n
(Amp)
i
s
(Amp)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-60
0
60
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
-40
0
40
time (sec)
0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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0
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0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2
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time (sec)
9. IJPEDS ISSN: 2088-8694
Shunt Active Filter Based On Radial Basis Function Neural Network … (Prakash Ch.Tah)
675
Table 2. Chart diagram showing source current THDs (in %) before and after compensation with ,
modified and RBFNN-PQ control schemes for simulations under ideal supply condition
Phase-a Phase-b Phase-c
Without APF 30.13 30.05 28.38
p-q Scheme 4.12 4.03 3.72
Modified p-q Scheme 3.41 3.46 3.14
RBFNN-PQ 3.07 3.03 2.94
Table 3. Chart diagram showing source current THDs (in %) before and after compensation with ,
modified and RBFNN-PQ control schemes for simulations under distorted supply condition.
Phase-a Phase-b Phase-c
Without APF 30.78 30.77 28.23
p-q Scheme 6.78 6.56 6.17
Modified p-q Scheme 4.39 4.31 4.05
RBFNN-PQ 3.62 3.54 3.68
It is clearly observed from the simulation results obtained under ideal supply that, the THD in
source current has been lowered down to nearly 3% with and modified schemes from the
uncompensated source current THD of nearly 30%. However, RBFNN-PQ scheme is found to be more
proficient, as it lowers down the source current THD to nearly 3.5% even during large change in load and
unbalanced loading conditions. Hence, all the control schemes are found to be successful in lowering down
the THDs in source current well below 5%. Under highly distorted supply, though modified scheme
works comparatively better than scheme, RBFNN-PQ scheme outperforms the other two schemes by
lowering down the source current THDs in three phases to 3.62%, 3.54% and 3.68% even under sudden load
change and unbalanced loading conditions.
7. CONCLUSION
A comparison between the Conventional p-q, modified p-q and RBFNN-PQ control schemes for
three-phase four-wire VSI-based APF is realized. The reference compensation currents for the four-wires are
extracted and Hysteresis PWM is carried out to generate switching signals for VSI. DC-link voltage has been
regulated successfully using a PSO-based PI controller, minimizing the undesirable power loss responsible
for degradation of APF performance, thereby providing optimal load compensation. MATLAB/Simulink
results showing the response of the control schemes under transient and steady-state conditions are presented.
All the control schemes discussed here are effective in harmonic compensation under ideal supply and satisfy
the IEEE-519 Standards on harmonic limits. Under distorted supply, though modified p-q scheme lowers
down the THD to values smaller than Conventional p-q, it fails to bring down the THD below 5%, which can
be seen from Table 3. In contrast, RBFNN-PQ scheme yields the lowest values of source current THDs. The
excessive neutral current has been compensated by all the control schemes under all kinds of supplies. This
proves that, RBFNN-PQ scheme is the best control scheme to be employed in shunt APF compared to the
other two mentioned control schemes.
REFERENCES
[1] H. Akagi, "New trends in active filters for power conditioning," Industry Applications, IEEE Transactions on, vol.
32, pp. 1312-1322, 1996.
[2] T. C. Green and J. H. Marks, "Control techniques for active power filters," Electric Power Applications, IEE
Proceedings, vol. 152, pp. 369-381, 2005.
[3] H. Akagi, H. Kanazawa and Y. Nabae, “Instantaneous Reactive Power Compensators Comprising Switching
Devices without Energy Storage Components,” IEEE Transactions on Industry Applications, vol. IA-20, no. 3, pp.
625-630, 1984.
[4] Z. Peng, et al., “Harmonic and Reactive Power Compensation Based on the Generalized Instantaneous Reactive
Power Theory for Three-Phase Four-Wire Systems,” IEEE Transactions on Power Electronics, vol. 13, no. 5, pp.
1174-1181, 1998.
[5] B. Singh, K. Al-Haddad and A. Chandra, "A review of active filters for power quality improvement," Industrial
Electronics, IEEE Transactions on, vol. 46, pp. 960-971, 1999.
[6] S. Mikkili and A. K. Panda, “Simulation and RTDS Hardware Implementation of SHAF for Mitigation of Current
Harmonics with p-q and id-iq Control Strategies Using PI Controller,” International Journal of Engineering,
Technology & Applied Science Research, vol. 1, no.3, 2011, pp. 54-62.
10. ISSN: 2088-8694
IJPEDS Vol. 8, No. 2, June 2017 : 667 – 676
676
[7] M. Suresh, A. K. Panda and Y. Suresh, “Fuzzy Controller Based 3-Phase 4-Wire Shunt Active Filter for Mitigation
of Current Harmonics with Combined p-q and id-iq Control Strategies,” Journal of Energy and Power Engineering,
Vol. 3, No. 1, 2011, pp. 43-52.
[8] Y.Kusuma Latha, Ch.Saibabu, Y.P.Obulesh” Control Strategy for Three Phase Shunt Active Power Filter with
Minimum Current Measurements,” International Journal of Electrical and Computer Engineering (IJECE), vol.1,
no.1, pp. 31-42, 2011.
[9] S. S. Haykin 1931-, Neural Networks: A Comprehensive Foundation /. Upper Saddle River, N.J.: Prentice Hall,
c1999.
[10] J.Moody, “Fast learning in networks of locally-tuned processing units”, Neural Computing, vol.1, pp.281, 1989.
[11] G. W. Chang, Cheng-I Chen and Yu-Feng Teng, "Radial-Basis-Function-Based Neural Network for Harmonic
Detection, “ IEEE Transactions on Industrial Electronics, vol. 57, pp. 2171-2179, 2010.
[12] A. Zouidi, F. Fnaiech, K. Al-Haddad and S. Rahmani, "Adaptive linear combiners a robust neural network
technique for on line harmonic tracking," Industrial Electronics, 2008. IECON 2008. 34th Annual Conference of
IEEE, pp. 530-534, 2008.
[13] R. Yousef, "Training radial basis function networks using reduced sets as center points," International Journal of
Information Technology, vol. 2, pp. 21, 2005.
[14] Mridul Jha, S.P. Dubey ,” Neuro-Fuzzy based Controller for a Three-Phase Four-Wire Shunt Active Power Filter”,
International Journal of Power Electronics and Drive System (IJPEDS), vol.1, no.2, pp. 148~155, 2011.
[15] G. W. Chang, C. I. Chen, Y. F. Teng ” An Application of Radial Basis Function Neural Network For Harmonics
Detection,” in Proc 2008 Harmonics and Quality of Power 13th International Conference, pp.1-5.
BIOGRAPHIES OF AUTHORS
Prakash Chandra Tah received his Bachelors in Electrical Engineering from Indira Gandhi
Institute of Technology,Odisha, India in 2002. He completed his Masters in Technology
(Electronics system and communication) from National Institute of Technology Rourkela,
Rourkela, India in 2005.He worked asSr. Lecturer and Assistant Professor for four year in the
Electrical and Electronics Engineering Dept. of KIIT University. Currently he is working as a
Sr.Tech.in Power and blowing station,Rourkela steel plant,SAIL. His current research interests
include power converters, active filtering, power conditioning, AC and DC drives, neural network
and fuzzy logic based controller design for Electrical drives, Genetic Algorithm Optimization.
Anup Kumar Panda:. He received the B.Tech in Electrical Engineering from Sambalpur
University, India in 1987. He received the M.Tech in Power Electronics and Drives from Indian
Institute of Technology, Kharagpur, India in 1993 and Ph.D. in 2001 from Utkal University. Join
as a faculty in IGIT, Sarang in 1990. Served there for eleven years and then join National Institute
of Technology, Rourkela in January 2001 as an assistant professor and currently continuing as a
Professor in the Department of Electrical Engineering. He has published over hundred articles in
journals and conferences. He has completed two MHRD projects and one NaMPET project.
Guided eight Ph.D. scholars and currently guiding twelve scholars in the area of Power
Electronics & Drives. His research interest includes Design of high frequency power conversion
circuits and Applications of Soft Computing Techniques, improvement in Multilevel Converter
Topology, Power Factor Improvement, Power quality Improvement in power system and Electric
drives.
Bibhu Prasad Panigrahi: He received the B.Sc.(Engineering) degree in Electrical Engineering with
Honors from VSSUT, Burla (then University College of Engineering, Burla, Sambalpur
University) Odisha, India in the year 1989 and the M.Tech. (Power Electronics and Power
Systems) degree from Indian Institute of Technology, Bombay, Mumbai, India in the year 1997.
He obtained his Ph.D. degree in Electrical Engineering from Indian Institute of Technology,
Kharagpur, India in the year 2007. He has worked as Assistant Engineer in Fertilizer Corporation
of India Limited for two years from 1989 to 1991. After spending few months as Executive
Trainee in Nuclear Power Corporation of India Limited, he switched over to academics and joined
Electrical Engineering Department of Indira Gandhi Institute of Technology (IGIT), Sarang,
Dhenkanal, Orissa (India) as a Lecturer in April 1992. In April 1997, he became Senior Lecturer
in the same department and in April 2002, he was promoted to Lecturer (Selection
Grade)/Assistant Professor. In March 2009, he joined as Professor in the same Electrical
Engineering Department of IGIT, Sarang and heading the department since then. He has published
forty nine research papers in various journals and conference proceedings both at national and
international level. His research interest includes Electrical Machines, Power Electronics and
Power System.