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.
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.
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.
Power quality improvement of grid interconnected distribution system using fs...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Coordinated planning in improving power quality considering the use of nonlin...IJECEIAES
Power quality has an important role in the distribution of electrical energy. The use of non-linear load can generate harmonic spread which can reduce the power quality in the radial distribution system. This research is in form of coordinated planning by combining distributed generation placement, capacitor placement and network reconfiguration to simultaneously minimize active power losses, total harmonic distortion (THD), and voltage deviation as an objective function using the particle swarm optimization method. This optimization technique will be tested on two types of networks in the form 33-bus and 69-bus IEEE Standard Test System to show effectiveness of the proposed method. The use of MATLAB programming shows the result of simulation of increasing power quality achieved for all scenario of proposed method.
Power quality improvement of grid interconnected distribution system using fs...eSAT Journals
Abstract This paper presents a fuzzy step size least mean square (LMS) algorithm for grid connected renewable energy source. The main objective is to mitigate the harmonics and the neutral current compensation. The conventional controllers may fail due to the rapid change in the dynamics of the highly non-linear system. The fuzzy step size least mean square (FSS-LMS) algorithm in handling theuncertainties and learning from the processes is proved to be advantageous while the inverter operating at fluctuatingoperating conditions. The inverter is controlled tocompensate the harmonics and current imbalance of a three phase four wire non-linear load with generatedrenewable power injection in to the grid.The grid will always supply/absorb a balanced set offundamental currents at unity power factor even in the presence of three phase four wire non-linear unbalance load at point of common coupling(PCC).The proposed system is developed and simulated inMATLAB/SimPowerSystem environment under differentoperating conditions.
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.
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.
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.
Power quality improvement of grid interconnected distribution system using fs...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Coordinated planning in improving power quality considering the use of nonlin...IJECEIAES
Power quality has an important role in the distribution of electrical energy. The use of non-linear load can generate harmonic spread which can reduce the power quality in the radial distribution system. This research is in form of coordinated planning by combining distributed generation placement, capacitor placement and network reconfiguration to simultaneously minimize active power losses, total harmonic distortion (THD), and voltage deviation as an objective function using the particle swarm optimization method. This optimization technique will be tested on two types of networks in the form 33-bus and 69-bus IEEE Standard Test System to show effectiveness of the proposed method. The use of MATLAB programming shows the result of simulation of increasing power quality achieved for all scenario of proposed method.
Power quality improvement of grid interconnected distribution system using fs...eSAT Journals
Abstract This paper presents a fuzzy step size least mean square (LMS) algorithm for grid connected renewable energy source. The main objective is to mitigate the harmonics and the neutral current compensation. The conventional controllers may fail due to the rapid change in the dynamics of the highly non-linear system. The fuzzy step size least mean square (FSS-LMS) algorithm in handling theuncertainties and learning from the processes is proved to be advantageous while the inverter operating at fluctuatingoperating conditions. The inverter is controlled tocompensate the harmonics and current imbalance of a three phase four wire non-linear load with generatedrenewable power injection in to the grid.The grid will always supply/absorb a balanced set offundamental currents at unity power factor even in the presence of three phase four wire non-linear unbalance load at point of common coupling(PCC).The proposed system is developed and simulated inMATLAB/SimPowerSystem environment under differentoperating conditions.
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.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
A NOVEL TCHNOLOGY FOR HARMONICS AND UNBALANCE COMPENSATION IN ELECTRIC TRACTI...ijiert bestjournal
Power quality problems in power systems have been i mproved due to nonlinear loads. To compensate these problems Direct Power Compensator was proposed in this paper. A Direct Power Compensator (DPC) is proposed in this paper to elim inate the harmonic currents,compensate power factor and voltage unbalance problems created by th e nonlinear loads present in three phase systems. A DPC contains back to back converter by sharing th e same dc link power and v/v transformer to provide a voltage balance in transmission line. Hys teresis harmonic current regulator is used to produce pulse for back to back converter. A control ler maintains the dc-link voltage and compensates the power factor,harmonic currents. A comparative analysis for traction system with and without DPC was performed using MATLAB Simulink . Simulation results show the controller advantages and the applicability of the proposed me thod in railway systems.
Harmonic analysis and Power factor improvement with UPQC under two Novel cont...IJERA Editor
This paper presents unified power quality conditioner (UPQC)for power quality improvements in terms of
harmonics compensation and power factor correction in a three-phase four-wire distribution system.The UPQC
is implemented with PWM controlled voltage source converter (VSC) and switching patterns are generated
through Indirect PI and Synchronous Reference Frame controller. The selected topology for voltage source
converter is the three-leg and six-leg VSC for Indirect PI and Synchronous reference frame (SRF) control
strategies respectively. The behavior of UPQC has been analyzed by considering a case study with switching of
three phase half bridge diode rectifier and a parallel star connected unbalanced R-L loads. Harmonic spectrum
of the source current and load voltage are compared in between without UPQC and with UPQC by considering
both control strategies. The complete system has been modeled using MATLAB software with its stimulus’s
sim power system toolboxes.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Abstract: In this paper three phase load flow analysis on four bus system using Mi Power software is reformed. As power system never operates under steady state condition therefore single phase load flow analysis doesn’t provide accurate results. Hence three phase load flow analysis which can be performed under different contingencies, provide data when system is unbalanced. The system is analysing on the basis of parameter values in MW & MVAR for transmission line and generator buses. Harmonic values of resistance, reactance, and susceptance can predict the condition of small and large kind of system network. This type of analysis is useful for solving the power flow problem in different power systems which will useful to calculate the unknown parameter.
Comparative analysis of improved high performance direct power control of thr...eSAT Journals
Abstract
Direct Power Control with switching table control produces irregular ripples and variable switching frequency. In the improved DPC of PWM rectifiers using fractional control period of the active voltage vector and the rest period for the null vector not only makes it line side inductance independent of the circuit and is very simple to implement due to the duty cycle concept. By simulation it is identified that the level of distortion as well as regulation of the DC link voltage with control of power factor improves the overall performance of the drive. The improved Direct Power Control (DPC) PWM methodology is comprehensively analyzed and studied for three phase rectifiers and compared with the classical DPC with PLL. The MATLAB simulations shows the effectiveness in obtaining unity power factor and constant dc link voltage control. The power ripples are considerably reduced and input sinusoidal grid currents are obtained.
Keywords— Direct power control, instantaneous active and reactive power, pulse width modulation, duty cycle, dc link control, unity power factor
A voltage sensitivity index application for power system load shedding consid...IJAEMSJORNAL
This paper proposes a method for calculating the minimum amount of power load needed to shed and distributing it for each load bus in order to recover the frequency and voltage back to the allowable range. Based on the consideration of the primary control of the turbine governor and the reserve power of the generators for secondary control, the minimum amount of load shedding was calculated in order to recover the frequency of the power system. Computation and analysis of Voltage Sensitivity Index (VSI) of the load bus to prioritize distribution of the amount power load shedding at these positions. The lower the load bus have the Voltage Sensitivity Index (VSI), the higher the amount of load shedding will shed and vice versa. With this technique, frequency and voltage value are still within allowable range, and a large amount of load shedding could be avoided, hence, saved from economic losses, and customer service interruption. The effectiveness of the proposed method tested on the IEEE 37 bus 9 generators power system standard has demonstrated the effectiveness of this method.
Static VAR Compensators (SVCs) is a Flexible Alternating Current Transmission System (FACTS) device that can control the power flow in transmission lines by injecting capacitive or inductive current components at the midpoint of interconnection line or in load areas. This device is capable of minimizing the overall system losses and concurrently improves the voltage stability. A line index, namely SVSI becomes indicator for the placement of SVC and the parameters of SVCs are tuned by using the multi-objective evolutionary programming technique, effectively able to control the power. The algorithm was tested on IEEE-30 Bus Reliability Test System (RTS). Comparative studies were conducted based on the performance of SVC in terms of their location and sizing for installations in power system.
Series of blackouts encountered in recent years in power system have been occurred because either of voltage or angle instability or both together was not detected within time and progressive voltage or angle instability further degraded the system condition, because of increase in loading. This paper presents the real-time assessment methodology of voltage stability using Phasor Measurement Unit (PMU) with observability of load buses only in power network. PMUs are placed at strategically obtained location such that minimum number of PMU’s can make all load buses observable. Data obtained by PMU’s are used for voltage stability assessment with the help of successive change in the angle of bus voltage with respect to incremental load, which is used as on-line voltage stability predictor (VSP). The real-time voltage phasors obtained by PMU’s are used as real time voltage stability indicator. The case study has been carried out on IEEE-14 bus system and IEEE-30 bus systems to demonstrate the results.
Heuristic remedial actions in the reliability assessment of high voltage dire...IJECEIAES
Planning of high voltage direct current (HVDC) grids requires inclusion of reliability assessment of alternatives under study. This paper proposes a methodology to evaluate the adequacy of voltage source converter/VSCHVDC networks. The methodology analyses the performance of the system using N-1 and N-2 contingencies in order to detect weaknesses in the DC network and evaluates two types of remedial actions to keep the entire system under the acceptable operating limits . The remedial actions are applied when a violation of these limits on the DC system occurs; those include topology changes in the network and adjustments of power settings of VSC converter stations. The CIGRE B4 DC grid test system is used for evaluating the reliability/adequacy performance by means of the proposed methodology in this paper. The proposed remedial actions are effective for all contingencies; then, numerical results are as expected. This work is useful for planning and operation of grids based on VSC-HVDC technology.
Load shedding in power system considering the generator control and AHP algor...IJAEMSJORNAL
This paper proposes the load shedding method with considering the ranking load importance factors. The amount of shedding power is calculated based on the Primary and Secondary adjustments to restore the system’s frequency back to allowed range. The ranking and distribution shedding power on each load bus will be prosed based on the AHP algorithm. Loads with the smaller importance factor will have priority to be shed with the larger amount of shedding power and vice versa. The experimental and simulated results will be estimated on IEEE 37- bus system, the results show that the proposed method can help the frequency restores back to nominal range and reduce damages compared to the UFLS method.
Average dynamical frequency behaviour for multi-area islanded micro-grid netw...TELKOMNIKA JOURNAL
A micro-grid is a part of power system which able to operates in grid or islanding mode. The most important variable that able to give us information about the stability in islanded micro-grid network is the frequency dynamical responses. The frequency analysis for multi-area micro-grid network model may involve a complicated of mathematical equations. This makes the researcher intending to omit several unnecessary parameters in order to simplify the equations. The purpose of this paper is to show an approach to derive the mathematical equations to represent the average behavior of frequency dynamical responses for two different micro-grid areas. Both of networks are assumed to have non-identical distributed generator behavior with different parameters. The prime mover and speed governor systems are augmented with the general swing equation. The tie line model and the information of rotor angle was considered. Then, in the last section, the comparison between this technique with the conventional approach using centre of inertia (COI) technique was defined.
A Novel Approach for Allocation of Optimal Capacitor and Distributed Generati...paperpublications3
Abstract: Distributed generation (DG) units, based on their interfacing technology are divided into synchronous generator interfaced DGs, asynchronous generator interfaced DGs and inverter interfaced DGs. This paper presents two algorithms for allocation of optimal capacitor and distributed generation on radial distribution system. These algorithms predict requirement of reactive vars and real power and supplied via capacitor banks and distributed generation. This arrangement reduces transmission losses and voltage stability problem. Developed algorithm has been implemented on two IEEE 69 nodes and 52 nodes systems.
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.
Grid Interconnection of Renewable Energy Sources at the Distribution Level Wi...Pradeep Avanigadda
Renewable energy resources (RES) are being increasingly
connected in distribution systems utilizing power electronic
converters. This paper presents a novel control strategy for
achieving maximum benefits from these grid-interfacing inverters
when installed in 3-phase 4-wire distribution systems. The inverter
is controlled to perform as a multi-function device by incorporating
active power filter functionality. The inverter can thus be
utilized as: 1) power converter to inject power generated from
RES to the grid, and 2) shunt APF to compensate current unbalance,
load current harmonics, load reactive power demand and
load neutral current. All of these functions may be accomplished
either individually or simultaneously. With such a control, the
combination of grid-interfacing inverter and the 3-phase 4-wire
linear/non-linear unbalanced load at point of common coupling
appears as balanced linear load to the grid. This new control
concept is demonstrated with extensive MATLAB/Simulink simulation
studies and validated through digital signal processor-based
laboratory experimental results.
Index Terms—Active power filter
Hybrid energy storage system control analogous to power quality enhancement o...IJECEIAES
Increasing nonlinear loads and power electronic converters lead to various power quality issues in microgrids (MGs). The interlinking converters (ILCs) can participate in these systems to harmonic control and power quality enhancement. However, ILC participation deteriorates the dc link voltage, system stability, and storage lifetime due to oscillatory current phenomena. To address these problems, a new control strategy for a hybrid energy storage system (HESS) is proposed to eliminate the adverse effects of the harmonic control operation of ILC. Specifically, battery and super-capacitor (SC) are used as HESSs that provide low and high power frequency load, respectively. The proposed strategy tries to compensate the current oscillation imposed by ILC with fuzzy control of HESS. In this method, a proportional-resonant (PR) controller integrated with harmonic compensator (HC) is employed to control the ILC for power quality enhancement and oscillatory current elimination. The main advantages of the proposed strategy are to reduce DGs power fluctuations, precise DC bus voltage regulation for generation and load disturbances, improved grid power quality under nonlinear load and transition conditions. The performance of the proposed method for isolated and grid-connected modes is verified using simulation studies in the MATLAB software environment.
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.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
A NOVEL TCHNOLOGY FOR HARMONICS AND UNBALANCE COMPENSATION IN ELECTRIC TRACTI...ijiert bestjournal
Power quality problems in power systems have been i mproved due to nonlinear loads. To compensate these problems Direct Power Compensator was proposed in this paper. A Direct Power Compensator (DPC) is proposed in this paper to elim inate the harmonic currents,compensate power factor and voltage unbalance problems created by th e nonlinear loads present in three phase systems. A DPC contains back to back converter by sharing th e same dc link power and v/v transformer to provide a voltage balance in transmission line. Hys teresis harmonic current regulator is used to produce pulse for back to back converter. A control ler maintains the dc-link voltage and compensates the power factor,harmonic currents. A comparative analysis for traction system with and without DPC was performed using MATLAB Simulink . Simulation results show the controller advantages and the applicability of the proposed me thod in railway systems.
Harmonic analysis and Power factor improvement with UPQC under two Novel cont...IJERA Editor
This paper presents unified power quality conditioner (UPQC)for power quality improvements in terms of
harmonics compensation and power factor correction in a three-phase four-wire distribution system.The UPQC
is implemented with PWM controlled voltage source converter (VSC) and switching patterns are generated
through Indirect PI and Synchronous Reference Frame controller. The selected topology for voltage source
converter is the three-leg and six-leg VSC for Indirect PI and Synchronous reference frame (SRF) control
strategies respectively. The behavior of UPQC has been analyzed by considering a case study with switching of
three phase half bridge diode rectifier and a parallel star connected unbalanced R-L loads. Harmonic spectrum
of the source current and load voltage are compared in between without UPQC and with UPQC by considering
both control strategies. The complete system has been modeled using MATLAB software with its stimulus’s
sim power system toolboxes.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Abstract: In this paper three phase load flow analysis on four bus system using Mi Power software is reformed. As power system never operates under steady state condition therefore single phase load flow analysis doesn’t provide accurate results. Hence three phase load flow analysis which can be performed under different contingencies, provide data when system is unbalanced. The system is analysing on the basis of parameter values in MW & MVAR for transmission line and generator buses. Harmonic values of resistance, reactance, and susceptance can predict the condition of small and large kind of system network. This type of analysis is useful for solving the power flow problem in different power systems which will useful to calculate the unknown parameter.
Comparative analysis of improved high performance direct power control of thr...eSAT Journals
Abstract
Direct Power Control with switching table control produces irregular ripples and variable switching frequency. In the improved DPC of PWM rectifiers using fractional control period of the active voltage vector and the rest period for the null vector not only makes it line side inductance independent of the circuit and is very simple to implement due to the duty cycle concept. By simulation it is identified that the level of distortion as well as regulation of the DC link voltage with control of power factor improves the overall performance of the drive. The improved Direct Power Control (DPC) PWM methodology is comprehensively analyzed and studied for three phase rectifiers and compared with the classical DPC with PLL. The MATLAB simulations shows the effectiveness in obtaining unity power factor and constant dc link voltage control. The power ripples are considerably reduced and input sinusoidal grid currents are obtained.
Keywords— Direct power control, instantaneous active and reactive power, pulse width modulation, duty cycle, dc link control, unity power factor
A voltage sensitivity index application for power system load shedding consid...IJAEMSJORNAL
This paper proposes a method for calculating the minimum amount of power load needed to shed and distributing it for each load bus in order to recover the frequency and voltage back to the allowable range. Based on the consideration of the primary control of the turbine governor and the reserve power of the generators for secondary control, the minimum amount of load shedding was calculated in order to recover the frequency of the power system. Computation and analysis of Voltage Sensitivity Index (VSI) of the load bus to prioritize distribution of the amount power load shedding at these positions. The lower the load bus have the Voltage Sensitivity Index (VSI), the higher the amount of load shedding will shed and vice versa. With this technique, frequency and voltage value are still within allowable range, and a large amount of load shedding could be avoided, hence, saved from economic losses, and customer service interruption. The effectiveness of the proposed method tested on the IEEE 37 bus 9 generators power system standard has demonstrated the effectiveness of this method.
Static VAR Compensators (SVCs) is a Flexible Alternating Current Transmission System (FACTS) device that can control the power flow in transmission lines by injecting capacitive or inductive current components at the midpoint of interconnection line or in load areas. This device is capable of minimizing the overall system losses and concurrently improves the voltage stability. A line index, namely SVSI becomes indicator for the placement of SVC and the parameters of SVCs are tuned by using the multi-objective evolutionary programming technique, effectively able to control the power. The algorithm was tested on IEEE-30 Bus Reliability Test System (RTS). Comparative studies were conducted based on the performance of SVC in terms of their location and sizing for installations in power system.
Series of blackouts encountered in recent years in power system have been occurred because either of voltage or angle instability or both together was not detected within time and progressive voltage or angle instability further degraded the system condition, because of increase in loading. This paper presents the real-time assessment methodology of voltage stability using Phasor Measurement Unit (PMU) with observability of load buses only in power network. PMUs are placed at strategically obtained location such that minimum number of PMU’s can make all load buses observable. Data obtained by PMU’s are used for voltage stability assessment with the help of successive change in the angle of bus voltage with respect to incremental load, which is used as on-line voltage stability predictor (VSP). The real-time voltage phasors obtained by PMU’s are used as real time voltage stability indicator. The case study has been carried out on IEEE-14 bus system and IEEE-30 bus systems to demonstrate the results.
Heuristic remedial actions in the reliability assessment of high voltage dire...IJECEIAES
Planning of high voltage direct current (HVDC) grids requires inclusion of reliability assessment of alternatives under study. This paper proposes a methodology to evaluate the adequacy of voltage source converter/VSCHVDC networks. The methodology analyses the performance of the system using N-1 and N-2 contingencies in order to detect weaknesses in the DC network and evaluates two types of remedial actions to keep the entire system under the acceptable operating limits . The remedial actions are applied when a violation of these limits on the DC system occurs; those include topology changes in the network and adjustments of power settings of VSC converter stations. The CIGRE B4 DC grid test system is used for evaluating the reliability/adequacy performance by means of the proposed methodology in this paper. The proposed remedial actions are effective for all contingencies; then, numerical results are as expected. This work is useful for planning and operation of grids based on VSC-HVDC technology.
Load shedding in power system considering the generator control and AHP algor...IJAEMSJORNAL
This paper proposes the load shedding method with considering the ranking load importance factors. The amount of shedding power is calculated based on the Primary and Secondary adjustments to restore the system’s frequency back to allowed range. The ranking and distribution shedding power on each load bus will be prosed based on the AHP algorithm. Loads with the smaller importance factor will have priority to be shed with the larger amount of shedding power and vice versa. The experimental and simulated results will be estimated on IEEE 37- bus system, the results show that the proposed method can help the frequency restores back to nominal range and reduce damages compared to the UFLS method.
Average dynamical frequency behaviour for multi-area islanded micro-grid netw...TELKOMNIKA JOURNAL
A micro-grid is a part of power system which able to operates in grid or islanding mode. The most important variable that able to give us information about the stability in islanded micro-grid network is the frequency dynamical responses. The frequency analysis for multi-area micro-grid network model may involve a complicated of mathematical equations. This makes the researcher intending to omit several unnecessary parameters in order to simplify the equations. The purpose of this paper is to show an approach to derive the mathematical equations to represent the average behavior of frequency dynamical responses for two different micro-grid areas. Both of networks are assumed to have non-identical distributed generator behavior with different parameters. The prime mover and speed governor systems are augmented with the general swing equation. The tie line model and the information of rotor angle was considered. Then, in the last section, the comparison between this technique with the conventional approach using centre of inertia (COI) technique was defined.
A Novel Approach for Allocation of Optimal Capacitor and Distributed Generati...paperpublications3
Abstract: Distributed generation (DG) units, based on their interfacing technology are divided into synchronous generator interfaced DGs, asynchronous generator interfaced DGs and inverter interfaced DGs. This paper presents two algorithms for allocation of optimal capacitor and distributed generation on radial distribution system. These algorithms predict requirement of reactive vars and real power and supplied via capacitor banks and distributed generation. This arrangement reduces transmission losses and voltage stability problem. Developed algorithm has been implemented on two IEEE 69 nodes and 52 nodes systems.
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.
Grid Interconnection of Renewable Energy Sources at the Distribution Level Wi...Pradeep Avanigadda
Renewable energy resources (RES) are being increasingly
connected in distribution systems utilizing power electronic
converters. This paper presents a novel control strategy for
achieving maximum benefits from these grid-interfacing inverters
when installed in 3-phase 4-wire distribution systems. The inverter
is controlled to perform as a multi-function device by incorporating
active power filter functionality. The inverter can thus be
utilized as: 1) power converter to inject power generated from
RES to the grid, and 2) shunt APF to compensate current unbalance,
load current harmonics, load reactive power demand and
load neutral current. All of these functions may be accomplished
either individually or simultaneously. With such a control, the
combination of grid-interfacing inverter and the 3-phase 4-wire
linear/non-linear unbalanced load at point of common coupling
appears as balanced linear load to the grid. This new control
concept is demonstrated with extensive MATLAB/Simulink simulation
studies and validated through digital signal processor-based
laboratory experimental results.
Index Terms—Active power filter
Hybrid energy storage system control analogous to power quality enhancement o...IJECEIAES
Increasing nonlinear loads and power electronic converters lead to various power quality issues in microgrids (MGs). The interlinking converters (ILCs) can participate in these systems to harmonic control and power quality enhancement. However, ILC participation deteriorates the dc link voltage, system stability, and storage lifetime due to oscillatory current phenomena. To address these problems, a new control strategy for a hybrid energy storage system (HESS) is proposed to eliminate the adverse effects of the harmonic control operation of ILC. Specifically, battery and super-capacitor (SC) are used as HESSs that provide low and high power frequency load, respectively. The proposed strategy tries to compensate the current oscillation imposed by ILC with fuzzy control of HESS. In this method, a proportional-resonant (PR) controller integrated with harmonic compensator (HC) is employed to control the ILC for power quality enhancement and oscillatory current elimination. The main advantages of the proposed strategy are to reduce DGs power fluctuations, precise DC bus voltage regulation for generation and load disturbances, improved grid power quality under nonlinear load and transition conditions. The performance of the proposed method for isolated and grid-connected modes is verified using simulation studies in the MATLAB software environment.
Load frequency control in co ordination with frequency controllable hvdc link...eSAT Journals
Abstract
In this paper decentralized load frequency control (LFC) for suppression of oscillations in multi-area power systems using fuzzy logic
controller was studied. A three area system is considered in which areas 1 and 2 and areas 1 and 3 are connected by HVDC
transmission links and areas 2 and 3 are connected by normal AC tie-line. The performance of the fuzzy logic controller is compared
with the conventional PI controller and the simulation results shows that fuzzy logic controller is very effective enhancing better
damping performance in non-linear conditions.
Keywords: Load Frequency Control, High Voltage Direct Current transmission Link, Proportional Integral Controller,
Fuzzy Logic Control.
ER Publication,
IJETR, IJMCTR,
Journals,
International Journals,
High Impact Journals,
Monthly Journal,
Good quality Journals,
Research,
Research Papers,
Research Article,
Free Journals, Open access Journals,
erpublication.org,
Engineering Journal,
Science Journals,
Adaptive Fuzzy PID Based Control Strategy For 3Phase 4Wire Shunt Active Filte...IJERA Editor
This paper presents a new control strategy for controlling the shunt active power filter to compensate reactive
power and to reduce the unwanted harmonics in the grid current. Shunt active filter act as a current source which
is connected in parallel with a non-linear load and controlled to produce the required compensating current. The
proposed control strategy is based on the fuzzy PID controller which is used for determining the reference
compensating currents of the three-phase shunt active power filters. Simulations are carried out using
MATLAB/SIMULINK to verify the performance of the proposed controller. The output shows the controller has
fast dynamic response high accuracy of tracking DC voltage reference and robust to load parameters variations
To eliminate the adverse effect from parameter variations as well as distorted grid conditions, a current control scheme of an LCL-filtered grid-connected inverter using a discrete integral sliding mode control (ISMC) and resonant compensation is presented. The proposed scheme is constructed based on the cascaded multiloop structure, in which three control loops are composed of grid-side current control, capacitor voltage control, and inverter-side current control. An active damping to suppress the resonance caused by LCL filter can be effectively realized by means of the inverter-side feedback control loop. Furthermore, the seamless transfer operation between the grid-connected mode and islanded mode is achieved by the capacitor voltage control loop. To retain a high tracking performance and robustness of the ISMC as well as an excellent harmonic compensation capability of the resonant control (RC) scheme at the same time, two control methods are combined in the proposed current controller. As a result, the proposed scheme yields a high quality of the injected grid currents and fast dynamic response even under distorted grid conditions. Furthermore, to reduce the number of sensors, a discrete-time reduced-order state observer is introduced. Simulation and experimental results are presented to demonstrate the effectiveness of the proposed scheme.
The use of distributed generation (DG) within distribution systems has increased for the last two decades due to worldwide increase in demand for electricity and governmental policy change from “conventional” energy to “green” energy. High levels of penetration of DG have many significant benefits but also come with many drawbacks such as voltage drop and power losses. This study presents the impact of DG at different locations in a distribution feeder in terms of the feeder voltage profile. A radial distribution system is simulated using PSCAD/EMTDC simulation software while changing the size and location of DG in the system. The obtained results are used for better understanding on the impact of DG on voltage profile in radial distribution feeder.
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.
4.power quality improvement in dg system using shunt active filterEditorJST
Injection of power generated by the wind turbine system into an electric grid mainly effects the power quality. The performance of this wind turbine and its power quality is determined on the basis of its measurement of power ratings as per IEEE standards. The influence of the wind turbine in the grid system concerning the power quality measurements are the active power, reactive power, variation of voltage, flicker, harmonics, and electrical behavior of switching operation. To mitigate the power quality problems this paper proposes the shunt compensator techniques. Here, the proposed system is verified experimentally using both STATCOM and TSC compensators. This control schemes for grid connected wind energy system is simulated using Matlab/Simulink.
Power quality optimization using a novel backstepping control of a three-phas...IJECEIAES
A novel nonlinear backstepping controller based on direct current (DC) link voltage control is proposed in three-phase grid-connected solar photovoltaic (PV) systems to control the active and reactive power flow between the PV system and the grid with improved power quality in terms of pure sinusoidal current injection with lower total harmonic distortion (THD), as well as to ensure unity power factor, or to compensate for reactive power required by the load, i.e., the electrical grid. The output power of the PV array is supplied to the grid through a boost converter with maximum power point tracking (MPPT) control and an inverter. Simulation results of the proposed controller show good robustness under nominal conditions, parameter variations, and load disturbances, which presents the main advantage of this controller as compared to an existing controller. The performance of this work was evaluated using a MATLAB/Simulink environment.
Design and Simulation of a Three Phase Power Converter Connected To a Distrib...IJERA Editor
The distributed generation systems based on renewable energy sources (photovoltaic, fuel cells, and storage systems such as ultra capacitors and batteries) are of great interest due to their low environmental impact and technical advantages such as improvements in voltage levels and reduced power losses when a distributed generation system is installed in radial lines. Two control algorithms were proposed to improve the grid-connected and intentional-islanding operations methods, in which the distributed generation system must detect the situation and switch from power or current to voltage as a control variable to provide constant rms voltage to the local loads. The power flow between the grid and the distributed generation is controlled by applying a power/voltage method that regulates the amplitude and the displacement of the grid voltage synthesized by the distributed generation, while a phase-locked loop algorithm is used to synchronize the grid and distributed generation.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Stability Improvement in Grid Connected Multi Area System using ANFIS Based S...IJMTST Journal
Generally, the non-conventional energy sources are being extensively used in case of power electronic
converter based distribution systems. This paper mainly focuses on the wind energy system integrating with
grid connected system and also improvement of power quality features. The wind energy power plant is
modelled based on associated equations. For improving this power quality problems, this paper proposes the
concepts of shunt converter controllers. This paper also proposes the concepts of ANFIS based Static
Compensator. And also the results are compared for this cases. Thus with such a control, a balanced load
currents are obtained even in the presence of non-linear load. The experimental setup is done in Matlab and
verified the simulation results
Power Quality Improvement of Grid Interconnection of renewable Energy Based D...IJERA Editor
This paper presents a grid interfacing inverter which compensates power quality problems and also interface Renewable Energy Sources with the help of electric grid. Renewable Energy Sources are being increasingly connected in distribution system utilizing power electronic converters. Grid interfacing inverter can be used: 1) To improve the transfer of active power harvested from RES; 2) To meet load reactive power demand support ; 3) To reduce current harmonics by incorporating the current harmonic compensator at point of common coupling(PCC) ; 4) current unbalance and neutral current compensation in case of 3-phase 4-wire system. The fuzzy logic can be used in many applications especially, when the process/models are complex to analyse by using classical methods. Mainly fuzzy logic controller is used to control DC capacitor voltage. Simulations are carried out using MATLAB/SIMULINK to verify the performance of the controller. The output shows the controller has fast dynamic response high accuracy of tracking DC voltage reference and robust to load parameters variations.
This paper presents a thorough control structure of the distributed generators inside the microgrid during both grid-connected and islanded operation modes. These control structures of the DGs voltage source inverters are implemented in synchronous reference frame (SRF) and controlled using linear PI controllers. By implementing the control structures, the desired real and reactive power can be efficiently transferred to the local loads and the utility load by the microgrid generating units. A modified droop control technique is introduced to facilitate the microgrid performance during both modes of operation. The active and reactive power sharing of the load demand between the utility grid and the microgrid can be performed by this drop control technique during the islanded mode. The system performance during intentional islanding event and utility load increase is investigated. The effectiveness of the offered control structures is confirmed through simulation results during both modes of operation.
Advance Technology in Application of Four Leg Inverters to UPQCIJPEDS-IAES
This article presents a novel application of four leg inverter with
conventional Sinusoidal Pulse Width Modulation (SPWM) Scheme to
Unified Power Quality Conditioner (UPQC). The Power Quality problem
became burning issues since the starting of high voltage AC transmission
system. Hence, in this article it has been discussed to mitigate the PQ issues
in high voltage AC systems through a three phase Unified Power Quality
Conditioner (UPQC) under various conditions, such as harmonic mitigation
scheme, non linear loads, sag and swell conditions as well. Also, it proposes
to control harmoincs with various artificial intelligent techniques. Thus
application of these control technique such as Neural Networks (ANN)
Fuzzy Logic makes the system performance in par with the standards
and also compared with existing system. The simulation results based on
MATLAB/Simulink are discussed in detail to support the concept developed
in the paper.
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
To view the webinar recording, go to:
https://www.rttsweb.com/jmeter-integration-webinar
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
Software Delivery At the Speed of AI: Inflectra Invests In AI-Powered QualityInflectra
In this insightful webinar, Inflectra explores how artificial intelligence (AI) is transforming software development and testing. Discover how AI-powered tools are revolutionizing every stage of the software development lifecycle (SDLC), from design and prototyping to testing, deployment, and monitoring.
Learn about:
• The Future of Testing: How AI is shifting testing towards verification, analysis, and higher-level skills, while reducing repetitive tasks.
• Test Automation: How AI-powered test case generation, optimization, and self-healing tests are making testing more efficient and effective.
• Visual Testing: Explore the emerging capabilities of AI in visual testing and how it's set to revolutionize UI verification.
• Inflectra's AI Solutions: See demonstrations of Inflectra's cutting-edge AI tools like the ChatGPT plugin and Azure Open AI platform, designed to streamline your testing process.
Whether you're a developer, tester, or QA professional, this webinar will give you valuable insights into how AI is shaping the future of software delivery.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
DevOps and Testing slides at DASA ConnectKari Kakkonen
My and Rik Marselis slides at 30.5.2024 DASA Connect conference. We discuss about what is testing, then what is agile testing and finally what is Testing in DevOps. Finally we had lovely workshop with the participants trying to find out different ways to think about quality and testing in different parts of the DevOps infinity loop.
1. G. KARTHIKEYAN
* et al.
ISSN:
2250
–
3676
[
IJESAT]
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE &
ADVANCED TECHNOLOGY
Volume
-
2, Issue
-
3,
61
2
–
6
1
8
2. IJESAT | May
-
Jun
2012
Available online @ http://www.ijesat.org
612
LOAD FREQUENCY CONTROL FOR THREE AREA SYSTEM WITH
TIME DELAYS USING FUZZY LOGIC CONTROLLER
G.Karthikeyan
1
,
S.Ramya
2
, Dr. S.Chandrasekar
3
1
Asst. professor(Sr. G), EEE,Sona College of Technology,Tamil Nadu,India,
gkarthikeyan_78@yahoo.com.
2
P.G Scholar, Sona College of Technology, Tamil Nadu, India,
sramyasct@yahoo.com.
3
Principal, Gnanamani College of Engineering, Tamil Nadu, India.
Abstract
The load
-
frequency control (LFC) is used to restore the balance between load and
generation in each control area by means of speed
3. control. The objective of LFC is to minimize the transient deviations and steady
state error to zero in advance. This paper i
nvestigates
LFC with time delays using
proportional integral (
PI) Controller and fuzzy logic controller for three area system using
MATLAB/SIMLINK. In this proposed system Area 1 and 2, Area 2 and 3 are
connected by frequency controllable High Voltage Dire
ct
Current transmission links and Area 2 and 3 is connected by normal AC tie
-
line. By using the system interconnections as the HVDC
link, the tie
-
line power modulation of HVDC link through interconnections is possible. The
advantage of incorporating time d
elays is
important for satisfactory dynamical responses. The HVDC transmission link is
to transfer power over long distance without an
y
frequency deviation.
Index Terms:
K
LFC,
ACE, Time delay, HVDC tie line
.
---------------------------------------------------------------------------------
***
----------------------------------------------------------------------------
4. 1. INTRODUCTION
Frequency changes in an interconnected powe
r system are the
direct result of imbalance between electrical load and the power
supplied by generators connected to the systems [6]. The
quality of power generating system is defined by three factors:
constancy of frequency, constancy of voltage and leve
l of
reliability. In actual power system operations, the load is
changing continuously and randomly, resulting in the
deviations of load frequency and the tie
-
line power between
any two areas from scheduled generation quantities. The aim of
LFC is to regul
ate the frequency to the nominal value and to
maintain the interchange power between control areas [9]. The
network frequency is maintained constant in order to run power
systems in parallel operation and also operating various motors
at desired speed in t
he system.
LFC is a very important factor in power system operation and
control for supplying sufficient and reliable electric power with
good quality. The main advantage of HVDC link is the
enhanced damping of AC transmission using power modulation
via a
n HVDC link in a parallel AC
-
DC interconnected power
5. system [11]. When an AC power system is subjected to a load
disturbance the system frequency may deviate from normal
operating frequency and it directly interrupt the operation of
power
and error
system.
To overcome this problem HVDC link
is mostly preferred in parallel with AC transmission line.
Normally LFC systems use PI controllers. Since they are
designed using a linear model, the non linearity’s of the system
are not considered [6] and these control
lers are commonly
tuned based on classical ,experience and trial and error
approach, They are incapable of obtaining good dynamical
performance in a multi area power system [1].
Now
-
a
-
days the LFC systems are faced by new uncertainties in
the electrical m
arket. To meet these uncertainties and to support
the control process an open communication infra structure is
important. In conventional LFC schemes dedicated
communication channels are used for transmit the
measurements to the control centre and then to
the generator
unit. The communication delays are considered as significant
uncertainties in the LFC due to the complexity of the power
6. system and cause the system instability. This also degrades the
system performance.
Thus the analysis of LFC model in th
e presence of time delays
is most important. Now
-
a
-
days many researchers concentrate
on LFC modelling/synthesis in the presence of time delays [1]
-
[5]. They mainly focused on the network delay models and the
communication network requirements.
In this paper, the power system with three areas having two
reheat turbine and one non reheat turbine is considered in
simulation study with time delays using PI controller and fuzzy
G. KARTHIKEYAN
* et al.
ISSN:
2250
–
3676
[
IJESAT]
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE &
ADVANCED TECHNOLOGY
Volume
-
2, Issue
7. -
3,
61
2
–
6
1
8
IJESAT | May
-
Jun
2012
Available online @ http://www.ijesat.org
613
logic controller. In the proposed structure Area 1 and 2, Area 1
and 3 ar
ea connected by frequency controllable HVDC
transmission link and Area 2 and 3 is connected by normal tie
-
line. The advantage of using HVDC links is to reduce long
distance transmission cost and power loss [7]. The purpose of
using FLC is that it provides
fast response, adequate
disturbance rejection an also provides effective result for
complex and non linear model. Finally the results of PI and
FLC are considered as shown at simulation results. The
controller improves effectively the damping of the oscill
ations
after the load deviation in one of the areas in the interconnected
8. system compared to conventional controllers.
2
.
PROPOSED
CONTROL STRATEGY
2.1.
Modelling of power generating units
2.1.1
Speed governing syst
em model
When the generator electrical load exceeds, the electrical power
exceeds the mechanical power input. This is compensated by
the kinetic energy stored in the rotating system, this cause the
generator frequency to fall. Speed governor model sense the
machine
speed and adjust the input valve to change the
mechanical output and to restore frequency at nominal value.
∆
푃
푣
푠
=
1
1
+
휏
10. 푚
푠
=
1
1
+
휏
푡
푠
∆
푝
푣
푠
B)
Generator m
odel
T
he synchronous machine as an ac generator driven by a
turbine is the device, which converts mechanical energy into
electrical energy.
In power system if there is any
change in
load cause change in frequency or speed of the generator unit in
the system.
∆
11. 퐹
푠
=
1
2
퐻
푠
(
∆
푃
푚
푠
−
∆
푝
푒
푠
)
C)
Load model
The load on a power system comprises of a variety of electrical
devices. Some of them are purely resistive.
Some are motor
loads with variable power frequency characteristics, and others
12. exhibit quite different characteristics. Since motor loads are a
dominant part of the electrical load, there is a need
to model the
effect of a change in frequency on the net l
oad drawn by the
system. The relationship between the changes in load due to the
change in frequency is given by
∆
푃
퐿
푓
푟
푒
푞
=
퐷
∆
휔
2.2.
Mod
elling of interconnected system
In an interconnected or multi area system load change in one
area will affect the generation in all other interconnected areas.
Tie line power flow should also be taken into account other
than change in frequency.
13. 2.2.1
Tie
-
line model and bias control
In an interconnected power system, different areas are
connected with each other via tie
-
lines. When the frequencies
in two areas are different, a power exchange occurs through the
tie
-
line the two areas.
In normal operation the power on the tie
-
line follo
ws from equation.
푃
푡
푖
푒
푓
푙
표
푤
=
14. 1
푋
푡
푖
푒
(
훽
1
−
훽
2
)
This tie
-
line flow is a steady
-
state quantity. For purpose of
analysis here, we will perturb the above
eq
uation to obtain
deviations from nominal flow as a function of deviations in
phase angle from
nominal.
∆
푃
18. 휔
1
−
휔
2
)
Where T is the tie
-
line stiffness coefficient.
From the
above discussion it is clear that the tie
-
line power
error is the integral of the frequency difference between the two
areas.
Suppose now that we have an interconnected power system
broken into two areas each having one generator. The areas are
connected
by a single transmission line. The power flow over
the transmission line will appear as a positive load to one area
and an equal but negative load to the other, or vice versa,
depending on the direction of flow. The direction of flow will
be dictated by th
e relative phase angle between the areas, which
is determined by the relative speed
-
deviations in the areas
Consider a three area system interconnected via the tie
19. -
line and
hence at steady state the equation becomes,
∆
ω
1
=
∆
ω
2
=
∆
ω
3
=
∆
ω
푑
(
∆
휔
1
)
푑
푡
=
22. * et al.
ISSN:
2250
–
3676
[
IJESAT]
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE &
ADVANCED TECHNOLOGY
Volume
-
2, Issue
-
3,
61
2
–
6
1
8
IJESAT | May
-
Jun
2012
Available online @ http://www.ijesat.org
614
I
f we consider the
23. 푖
푡
푕
control area, its net interchange equals
the sum of the megawatts on all m outgoing tie lines. As the
area control error
퐴
퐶
퐸
푖
ought to be reflective of the total
exchange of power it should thus be chosen of the form
퐴
퐶
퐸
푖
=
∆
푃
푖
푗
+
24. 퐵
푖
∆
푓
푖
푗
=
1
T
his error is added to the biased frequency error and the ACE.
The ACE is communicated
with all area generators that are
participating in the secondary LFC.
2.2.2
Three Area
LFC
Model
In an interconnected power system a group of generators are
closely coupled internally and swing in unison. The generator
turbines tend to have the same response
characteristics. Such a
group of generators are said to be coherent. This is referred to
as control area. The various control areas are generally
interconnected using transmission lines called “tie lines” which
allow the flow of active power from one area
to another when
25. required.
Fig 1:
Three area system
When an interconnected AC power system is subjected to a
load disturbance, system frequency may be considerably
disturbed and becomes oscillatory. By utilizing the system
interconnections as the
control channels of HVDC link, the tie
line power modulation of HVDC link through interconnections
is applicable for stabilizing the frequency oscillation of AC
system. The major advantages of HVDC link are long distance
overhead bulk power transmission, t
ransmission between
unsynchronized AC transmission and marine cable
transmission.
In this proposed model a HVDC transmission link is used to
transfer power from one area to another over a long distance
without any frequency deviation. Since it is frequenc
y
insensitive under the constant current control, Auxiliary
frequency controllers are widely used along with HVDC
transmission in order to improve the system performance.
These HVDC links are then frequency sensitive and may pose
some stability problems. A
load frequency controller corrects
any deviation of the power system after a change in load
demand.
Here each area requires only its local measurements. The
remote terminal measurements are avoided. The collection of
26. these local frequency controllers is
known as de
-
centralized
load frequency controller. In the presence of frequency
controllable HVDC links, frequency regulation of a receiving
area will cause frequency deviations in its sending ends. All the
local frequency controllers and affected AFC’s ar
e activated.
In this structure area 1 and 2 contain reheat type turbines and
area 3 uses non
-
reheat turbine. Area 2 and 3 are interconnected
through normal tie
-
line. It is assumed that both areas 2 and 3
may face large load changes that will cause a signi
ficant and
unacceptable frequency deviation. They are therefore linked to
area 1 via HVDC tie
-
lines for assistance in frequency
regulation.
2.3. Modelling of time delays
In this paper control delay is considered on the control input
and control output of
the LFC system. The delays on the
measured frequency and power tie
-
27. line flow from remote
terminal units to the control centre is considered on the area
control error(ACE) signal and the produced rise/lower signal
from the control centre to individual gene
ration units.
Fig 2:
Three control area with time delays
The communication delay is expressed by an exponential
function
푒
−
푠
휏
where
휏
gives the communication delay time
following a load disturbance with in a control area. The
frequency of the area
experiences a transient change and the
feedback mechanism comes into play and generates the
appropriate control
signal to make the generation readjust to
meet the load demand. The balance between the connected
control areas is achieved by detecting the fre
quency and tie
-
line
28. G. KARTHIKEYAN
* et al.
ISSN:
2250
–
3676
[
IJESAT]
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE &
ADVANCED TECHNOLOGY
Volume
-
2, Issue
-
3,
61
2
–
6
1
8
IJESAT | May
-
Jun
2012
Available online @ http://www.ijesat.org
615
power deviation via communication to generate the ACE signal
by PI and FLC and this control signal is submitted to the
29. participated generation companies via another communication
link, based on their participation factor.
2.3.1 Dynamic
model of LFC with time delay
For multi area LFC scheme, all generation units in each control
area are simplified as an equivalent generation unit. The
dynamic model of the multi
-
area power system including n
control areas as follows,
푥
푡
=
퐴
푥
푡
+
퐵
푢
푡
+
퐹
∆
푃
36. 푚
,
∆
푃
푣
,
∆
푃
푑
are
the deviations of frequency, the generator
mechanical output, valve position and load respectively.
ACE and
퐴
퐶
퐸
are the area control error and i
ts time
integration respectively.
Using ACE as the input the design for PI controller is as
follows,
푢
푡
=
51. area system the net tie
-
line power exchange
between each control area,
∆
푃
푡
푖
푒
푖
푛
푖
=
1
=
0
.
3.
CONFIGURATION OF POWER SYS
TEM
BASED ON PI AND FUZZY LOGIC
CONTROLLER
3.1
PI controller
The proportional plus integral controller produces an output
52. signal consisting of two terms
-
one proportional to error signal
and the other
proportional to the integral error signal.
The control input’s are,
푈
푖
−
퐾
푖
퐴
퐶
퐸
푖
푑
푡
휏
0
=
퐾
푖
56. 2, Issue
-
3,
61
2
–
6
1
8
IJESAT | May
-
Jun
2012
Available online @ http://www.ijesat.org
616
Fig 3:
Block diagram of single area PI controller.
In PI controller, the proportional term provides control action
equal to some multiple of the error and the integral term forces
steady state error to zero.
3.2
Fuzzy Logic Controller
Fuzzy logic controller’s (FL
C) are knowledge based controllers
usually derived from a knowledge acquisition process or
automatically synthesized from self
-
organizing control
architecture. It typically defines a non
57. -
linear mapping from the
system’s state space to the control space. Th
e advantages of
FLC’s are,
1) Controller parameters can be changed very quickly by the
system dynamics because no parameter estimation is required
in designing controller for non
-
linear system.
2) It provides an efficient way of coping with imperfec
t
information and offers flexibility in decision making process.
The basic configuration of fuzzy logic based LFC composes the
following components:
1)
A fuzzification interface.
2)
A knowledge base
3)
A decision making logic and
4)
A defuzzification interface
A unive
rsal mamdani type fuzzy controller has been simulated
for the LFC to damp out the oscillations due to instantaneous
perturbation as fast as possible. The parameters that affect the
system performance is considered as the inputs and they are
1)
58. The frequency e
rror
2)
The change of frequency error
The output of the controller is the incremental control action
i.e. incremental control output.
Fig 4:
Fuzzy logic controller for LFC
Here
푛
푒
,
푛
푐
푒
are scaling gains of error and change of error
and
푛
푢
,z
represent output control gain and maximum
membership function respectively
.
Fig 5:
Fuzzy Logic Controller Installed in
59. 푖
푡
푕
Area
Figure 5 describes the function of fuzzy logic controller in
power system. In this the tiangular membership function is
taken due its flexibility and also measurement of values is
accurate.
The next step is to fuzzifying the input
.
The universe of
discour
se of the inputs is divided into seven fuzzy sets of
triangular.
The first block inside the controller is Fuzzification,
which converts each piece of input data to degrees of
membership by a lookup in one or several membership
functions. The fuzzification
block thus matches the input data
with the conditions of the rules to determine how well the
condition of each rule matches that particular input instance.
There is a degree of membership for each linguistic term that
applies to that input variable.
Fig
7: Output control signal
Then rules are implemented to fuzzify the linguistic variables.
Fuzzy IF
60. -
THEN rules for LFC system is defined as follows,
If x is
퐴
푖
and y is
퐵
푖
then z is
퐶
푖
. The rules are created based on
mamdani type FLC. x is frequency
error and y is change in
frequency error.
NB
NM
NS
Z
PS
PM
PB
NB
NB
NB
NB
63. –
3676
[
IJESAT]
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE &
ADVANCED TECHNOLOGY
Volume
-
2, Issue
-
3,
61
2
–
6
1
8
IJESAT | May
-
Jun
2012
Available online @ http://www.ijesat.org
617
Finally defuzzification is done to get required crisp output. The
reverse of fuzzification is called Defuzzification. The use of
FLC produces required output in a linguistic variable. These
linguistic variables have to be transformed
to crisp output. The
centre of area defuzzification method is used.
64. The crisp output value u is the abscissa under the centre of
gravity of the fuzzy set,
푢
=
∀
휇
(
푥
푖
)
푥
푖
푖
휇
(
푥
푖
푖
)
Here
푥
푖
65. is a running point in a discrete universe, and
휇
푥
푖
is
its membership value in the membership function.
4.
SIMULATION RESULTS
The simulation results of three area system area are shown
below. In this six cases are considered based on the values used
for LFC parameters.
Case 1:
In this case we consider the
lowest parameters of three areas in
proposed structure.
Fig 8: Frequency deviation of 3 area system
-
case 1
Case 2:
Here nominal parameter is assumed to three areas.
Fig 11: Frequency deviation of 3 area system
-
case 4
Case 3:
Highest parameters are assumed to all three areas.
Fig 13: Frequency deviation of 3 area system
-
66. case 6
CONCLUSION
In this paper, three area load frequency control with time delays
are analysed using PI and fuzzy logic controller in co
-
ordination
with frequency controllable HVDC links. The results
are shown that by using the time delay the dynamic response of
the system will increase and the degradation in the system
performance can be compensated effectively using HVDC link.
By simulation study, t
he fuzzy logic controller is very effective
in suppressing the frequency oscillations caused by rapid load
disturbances and it will improve the system performance by
effectively reduce the overshoot compared to PI controller.
REFERENCES
[1] Hassan Bevrani
, Takashi Hiyama, “On Load
-
Frequency
Regulation with Time Delays: Design and Real
-
Time
Implementation”, IEEE transactions on energy conversion,
Vol.24, No. 1, March 2009.
[2] L. Jiang, W. Yao, J. Cheng and Q.H. Wu, “ Delay
-
dependent Stability for Load Fre
quency Control with Constant
67. and Time
-
Varying Delays”, IEEE transactions 2009.
[3] S. Bhowmik, K.Tomosovic, and A. Bose, “Communication
models for third party load frequency control”, IEEE
Trans.Power syst., vol. 19, no. 1, pp. 543
-
548, Feb. 2004.
[4] X.
Yu and K. Tomosovic, “Application of linear matrix
inequalities for load frequency control with communication
delays”, IEEE Trans.Power system technol., vol. 1, pp. 139
-
143, 2004.
[5] Kenji Okada, Gos Shirai and Ryuichi Yokoyana, “LFC
incorporating time
delay”, IEEE, Vol.75, July 1987.
G. KARTHIKEYAN
* et al.
ISSN:
2250
–
3676
[
IJESAT]
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE &
ADVANCED TECHNOLOGY
Volume
-
68. 2, Issue
-
3,
61
2
–
6
1
8
IJESAT | May
-
Jun
2012
Available online @ http://www.ijesat.org
618
[6] Z.B. Du, Y. Zhang, L. Liu, X.H. Guan, Y.X. Ni and F.F.
Wu, “Structure
-
preserved power
-
frequency slow dynamics
simulation of interconnected ac/dc power systems with AGC
consideration”, IEEE, June 2007.
[7]
IEEE
Committee Report, “HVDC controls for system
dynamic performance”, IEEE Transactions on Power Systems,
1992.
[8] P. Kundur
69. , “
Power System Stability and Control
”, New
York: McGraw
-
Hill, 1994.
[9] Nasser Jalleli, Donald N. Ewart, Lester H. Fink, Louis S.
Va
nslyck, “Understanding Automatic Generation Control”,
IEEE Transactions on power systems, vol. 7, No. 3, August
1992.
[10] Hadi Saadat, “Power System Analysis”, New Delhi:
McGraw
-
Hill, 2002.
[11] S. Ramesh, A. Krishnan, “Fuzzy Rule Based Load
Frequency C
ontrol in a Parallel AC
-
DC Interconnected Power
Systems through HVDC Link”, International Journal of
Computer Applications, 2010.
[12] C. Srinivasa Rao, Z. Naghizadeh, S. Mahdavi,
“Improvement of Dynamic Performance of Hydrothermal
System Under Open Marke
t Scenario Using Asynchronous Tie
-
lines”, World journal of modelling and simulation, 2007.
BIOGRAPHIES
70. G.Karthikeyan
was born in In
dia, in 1978.
He
received the B.E. degree in electrical
and electronics engineering from Mailam
Engineering
College
,
Mailam in 2003 and
M.E. degree in power systems engineering
from Sona college of Technology, Salem in
India, in 2006. Currently he is working as
Asst. Professor (Sr.G) at Sona college of
Technology in the department of Electrical and Electronics
Engineerin
g. His areas of research interest are power system
automation and artificial intelligence techniques applications in
electric power engineering.
S.Ramya
was born in India, in 1989. She
received the B.E.
degree in electrical and electronics engineering f
rom
Sona
College of Technology, Salem in 2010
.Currently she is pursuing
M.E. degree in
power systems engineering from Sona
71. college of Technology, Salem in India
.
Dr. S. Chandrasekar
was born in India, in
1975. He received the B.E. degree in
electrical
and electronics engineering from
Thiagarajar College Engineering Madurai
in 1996 and the M.E degree in power
system engineering from Coimbatore
Institute of Technology, Coimbatore in
India in 2001 and the Ph.D. degree from
the Indian Institute of Technolo
gy Madras, India in 2005. He
was a postdoctoral research fellow at the University of
Bologna, Italy from 2005 to 2006. Currently, he is working as a
Principal at Gnanamani College of Engineering. His research
interests include condition monitoring of power
apparatus and
systems, insulation engineering, signal processing and artificial
intelligence techniques applications in electric power
engineering.