Due to environmental concern and certain constraint on building a new power plant, renewable energy particularly distributed generation photovoltaic (DGPV) has becomes one of the promising sources to cater the increasing energy demand of the power system. Furthermore, with appropriate location and sizing, the integration of DGPV to the grid will enhance the voltage stability and reduce the system losses. Hence, this paper proposed a new algorithm for DGPV optimal location and sizing of a transmission system based on minimization of Fast Voltage Stability Index (FVSI) with considering the system constraints. Chaotic Mutation Immune Evolutionary Programming (CMIEP) is developed by integrating the piecewise linear chaotic map (PWLCM) in the mutation process in order to increase the convergence rate of the algorithm. The simulation was applied on the IEEE 30 bus system with a variation of loads on Bus 30. The simulation results are also compared with Evolutionary Programming (EP) and Chaotic Evolutionary Programming (CEP) and it is found that CMIEP performed better in most of the cases.
This paper presents the implementation of multiple distributed generations planning in distribution system using computational intelligence technique. A pre-developed computational intelligence optimization technique named as Embedded Meta EP-Firefly Algorithm (EMEFA) was utilized to determine distribution loss and penetration level for the purpose of distributed generation (DG) installation. In this study, the Artificial Neural Network (ANN) was used in order to solve the complexity of the multiple DG concepts. EMEFA-ANN was developed to optimize the weight of the ANN to minimize the mean squared error. The proposed method was validated on IEEE 69 Bus distribution system with several load variations scenario. The case study was conducted based on the multiple unit of DG in distribution system by considering the DGs are modeled as type I which is capable of injecting real power. Results obtained from the study could be utilized by the utility and energy commission for loss reduction scheme in distribution system.
Investigation of overvoltage on square, rectangular and L-shaped ground grid...IJECEIAES
Ground grid system is important for preventing the hazardous effects of overvoltage in high voltage substations due to fault current perhaps from lightning strike or device malfunction. Therefore, this study aimed to investigate the effects of overvoltage on square, rectangular and L-shaped ground grids with ground rods being distributed in mesh-pattern by using alternate transients program/electromagnetic transients program (ATP/EMTP) program. The models were simulated in the cases that 25 kAfault current being injected into the center or one of the corners of ground grids. The results showed that the highest level of overvoltage (6.3349 kV) was detected at the corner of rectangular ground grid when the fault current was injected into its corner. However, the lowest level of overvoltage was found when the fault current was injected into the center of square ground grid. The results from this study indicated that ATP/EMTP program was useful for preliminary investigation of overvoltage on ground grids of different shapes. The obtained knowledge could be beneficial for further designing of ground grid systems of high voltage substations to receive the minimal damages due to fault current.
Single core configurations of saturated core fault current limiter performanc...IJECEIAES
Economic growth with industrialization and urbanization lead to an extensive increase in power demand. It forced the utilities to add power generating facilities to cause the necessary demand-generation balance. The bulk power generating stations, mostly interconnected, with the penetration of distributed generation result in an enormous rise in the fault level of power networks. It necessitates for electrical utilities to control the fault current so that the existing switchgear can continue its services without upgradation or replacement for reliable supply. The deployment of fault current limiter (FCL) at the distribution and transmission networks has been under investigation as a potential solution to the problem. A saturated core fault current limiter (SCFCL) technology is a smart, scalable, efficient, reliable, and commercially viable option to manage fault levels in existing and future MV/HV supply systems. This paper presents the comparative performance analysis of two single-core SCFCL topologies impressed with different core saturations. It has demonstrated that the single AC winding configuration needs more bias power for affecting the same current limiting performance with an acceptable steady-state voltage drop contribution. The fault state impedance has a transient nature, and the optimum bias selection is a critical design parameter in realizing the SCFCL applications.
Power system operation considering detailed modelling of the natural gas supp...IJECEIAES
The energy transition from fossil-fuel generators to renewable energies represents a paramount challenge. This is mainly due to the uncertainty and unpredictability associated with renewable resources. A greater flexibility is requested for power system operation to fulfill demand requirements considering security and economic restrictions. In particular, the use of gas-fired generators has increased to enhance system flexibility in response to the integration of renewable energy sources. This paper provides a comprehensive formulation for modeling a natural gas supply network to provide gas for thermal generators, considering the use of wind power sources for the operation of the electrical system over a 24-hour period. The results indicate the requirements of gas with different wind power level of integration. The model is evaluated on a network of 20 NG nodes and on a 24-bus IEEE RTS system with various operative settings during a 24-hour period.
Performance comparison of distributed generation installation arrangement in ...journalBEEI
Placing Distributed Generation (DG) into a power network should be planned wisely. In this paper, the comparison of having different installation arrangement of real-power DGs in transmission system for loss control is presented. Immune-brainstorm-evolutionary programme (IBSEP) was chosen as the optimization technique. It is found that optimizing fixed-size DGs locations gives the highest loss reduction percentage. Apart from that, scattered small-sized DGs throughout a network minimizes transmission loss more than allocating one biger-sized DG at a location.
VOLTAGE PROFILE IMPROVEMENT AND LINE LOSSES REDUCTION USING DG USING GSA AND ...Journal For Research
In recent years, the power industry has experienced significant changes on the power distribution systems primarily due to the implementation of smart-grid technology and the incremental implementation of distributed generation. Distributed Generation (DG) is simply defined as the decentralization of power plants by placing smaller generating units closer to the point of consumption, traditionally ten mega-watts or smaller. The distribution power system is generally designed for radial power flow, but with the introduction of DG, power flow becomes bidirectional. Therefore this thesis focuses on testing various indices and using effective techniques for the optimal placement and sizing of the DG unit by minimizing power losses and voltage deviation. A 14-bus radial distribution system has been taken as the test system. The feasibility of the work lies on the fast execution of the programs as it would be equipped with the real time operation of the distribution system and it is seen that execution of the DG placement is quite fast and feasible with the optimization techniques used in this work.
Optimal SVC allocation via symbiotic organisms search for voltage security im...TELKOMNIKA JOURNAL
It is desirable that a power system operation is in a normal operating condition. However, the increase of load demand in a power system has forced the system to operate near to its stability limit whereby an increase in load poses a threat to the power system security. In solving this issue, optimal reactive power support via SVC allocation in a power system has been proposed. In this paper, Symbiotic Organisms Search (SOS) algorithm is implemented to solve for optimal allocation of SVC in the power system. IEEE 26 Bus Reliability Test System is used as the test system. Comparative studies are also conducted concerning Particle Swarm Optimization (PSO) and Evolutionary Programming (EP) techniques based on several case studies. Based on the result, SOS has proven its superiority by producing higher quality solutions compared to PSO and EP. The results of this study can benefit the power system operators in planning for optimal power system operations.
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.
This paper presents the implementation of multiple distributed generations planning in distribution system using computational intelligence technique. A pre-developed computational intelligence optimization technique named as Embedded Meta EP-Firefly Algorithm (EMEFA) was utilized to determine distribution loss and penetration level for the purpose of distributed generation (DG) installation. In this study, the Artificial Neural Network (ANN) was used in order to solve the complexity of the multiple DG concepts. EMEFA-ANN was developed to optimize the weight of the ANN to minimize the mean squared error. The proposed method was validated on IEEE 69 Bus distribution system with several load variations scenario. The case study was conducted based on the multiple unit of DG in distribution system by considering the DGs are modeled as type I which is capable of injecting real power. Results obtained from the study could be utilized by the utility and energy commission for loss reduction scheme in distribution system.
Investigation of overvoltage on square, rectangular and L-shaped ground grid...IJECEIAES
Ground grid system is important for preventing the hazardous effects of overvoltage in high voltage substations due to fault current perhaps from lightning strike or device malfunction. Therefore, this study aimed to investigate the effects of overvoltage on square, rectangular and L-shaped ground grids with ground rods being distributed in mesh-pattern by using alternate transients program/electromagnetic transients program (ATP/EMTP) program. The models were simulated in the cases that 25 kAfault current being injected into the center or one of the corners of ground grids. The results showed that the highest level of overvoltage (6.3349 kV) was detected at the corner of rectangular ground grid when the fault current was injected into its corner. However, the lowest level of overvoltage was found when the fault current was injected into the center of square ground grid. The results from this study indicated that ATP/EMTP program was useful for preliminary investigation of overvoltage on ground grids of different shapes. The obtained knowledge could be beneficial for further designing of ground grid systems of high voltage substations to receive the minimal damages due to fault current.
Single core configurations of saturated core fault current limiter performanc...IJECEIAES
Economic growth with industrialization and urbanization lead to an extensive increase in power demand. It forced the utilities to add power generating facilities to cause the necessary demand-generation balance. The bulk power generating stations, mostly interconnected, with the penetration of distributed generation result in an enormous rise in the fault level of power networks. It necessitates for electrical utilities to control the fault current so that the existing switchgear can continue its services without upgradation or replacement for reliable supply. The deployment of fault current limiter (FCL) at the distribution and transmission networks has been under investigation as a potential solution to the problem. A saturated core fault current limiter (SCFCL) technology is a smart, scalable, efficient, reliable, and commercially viable option to manage fault levels in existing and future MV/HV supply systems. This paper presents the comparative performance analysis of two single-core SCFCL topologies impressed with different core saturations. It has demonstrated that the single AC winding configuration needs more bias power for affecting the same current limiting performance with an acceptable steady-state voltage drop contribution. The fault state impedance has a transient nature, and the optimum bias selection is a critical design parameter in realizing the SCFCL applications.
Power system operation considering detailed modelling of the natural gas supp...IJECEIAES
The energy transition from fossil-fuel generators to renewable energies represents a paramount challenge. This is mainly due to the uncertainty and unpredictability associated with renewable resources. A greater flexibility is requested for power system operation to fulfill demand requirements considering security and economic restrictions. In particular, the use of gas-fired generators has increased to enhance system flexibility in response to the integration of renewable energy sources. This paper provides a comprehensive formulation for modeling a natural gas supply network to provide gas for thermal generators, considering the use of wind power sources for the operation of the electrical system over a 24-hour period. The results indicate the requirements of gas with different wind power level of integration. The model is evaluated on a network of 20 NG nodes and on a 24-bus IEEE RTS system with various operative settings during a 24-hour period.
Performance comparison of distributed generation installation arrangement in ...journalBEEI
Placing Distributed Generation (DG) into a power network should be planned wisely. In this paper, the comparison of having different installation arrangement of real-power DGs in transmission system for loss control is presented. Immune-brainstorm-evolutionary programme (IBSEP) was chosen as the optimization technique. It is found that optimizing fixed-size DGs locations gives the highest loss reduction percentage. Apart from that, scattered small-sized DGs throughout a network minimizes transmission loss more than allocating one biger-sized DG at a location.
VOLTAGE PROFILE IMPROVEMENT AND LINE LOSSES REDUCTION USING DG USING GSA AND ...Journal For Research
In recent years, the power industry has experienced significant changes on the power distribution systems primarily due to the implementation of smart-grid technology and the incremental implementation of distributed generation. Distributed Generation (DG) is simply defined as the decentralization of power plants by placing smaller generating units closer to the point of consumption, traditionally ten mega-watts or smaller. The distribution power system is generally designed for radial power flow, but with the introduction of DG, power flow becomes bidirectional. Therefore this thesis focuses on testing various indices and using effective techniques for the optimal placement and sizing of the DG unit by minimizing power losses and voltage deviation. A 14-bus radial distribution system has been taken as the test system. The feasibility of the work lies on the fast execution of the programs as it would be equipped with the real time operation of the distribution system and it is seen that execution of the DG placement is quite fast and feasible with the optimization techniques used in this work.
Optimal SVC allocation via symbiotic organisms search for voltage security im...TELKOMNIKA JOURNAL
It is desirable that a power system operation is in a normal operating condition. However, the increase of load demand in a power system has forced the system to operate near to its stability limit whereby an increase in load poses a threat to the power system security. In solving this issue, optimal reactive power support via SVC allocation in a power system has been proposed. In this paper, Symbiotic Organisms Search (SOS) algorithm is implemented to solve for optimal allocation of SVC in the power system. IEEE 26 Bus Reliability Test System is used as the test system. Comparative studies are also conducted concerning Particle Swarm Optimization (PSO) and Evolutionary Programming (EP) techniques based on several case studies. Based on the result, SOS has proven its superiority by producing higher quality solutions compared to PSO and EP. The results of this study can benefit the power system operators in planning for optimal power system operations.
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.
Resource aware wind farm and D-STATCOM optimal sizing and placement in a dist...IJECEIAES
Doubly fed induction generators (DFIG) based wind farms are capable of providing reactive power compensation. Compensation capability enhancement using reactors such as distributed static synchronous compensator (D-STATCOM) while connecting distribution generation (DG) systems to grid is imperative. This paper presents an optimal placement and sizing of offshore wind farms in a coastal distribution system that is emulated on an IEEE 33 bus system. A multi-objective formulation for optimal placement and sizing of the offshore wind farms with both the location and size constraints is developed. Teaching learning algorithm is used to optimize the multi-objective function constraining on the capacity and location of the offshore wind farms. The proposed formulation is a multi-objective problem for placement of the wind generator in the power system with dynamic wind supply to the power system. The random wind speed is generated as the input and the wind farm output generated to perform the optimal sizing and placement in the distributed system. MATLAB based simulation developed is found to be efficient and robust.
A NOVEL CONTROL STRATEGY FOR POWER QUALITY IMPROVEMENT USING ANN TECHNIQUE FO...IJERD Editor
The proposed system presents power-control strategies of a Micro grid-connected hybrid generation
system with versatile power transfer. This hybrid system allows maximum utilization of freely available
renewable energy sources like wind and photovoltaic energies. For this, an adaptive MPPT algorithm along with
standard perturbs and observes method will be used for the system.
The inverter converts the DC output from non-conventional energy into useful AC power for the
connected load. This hybrid system operates under normal conditions which include normal room temperature
in the case of solar energy and normal wind speed at plain area in the case of wind energy. However, designing
an optimal micro grid is not an easy task, due to the fact that primary energy carriers are changeable and
uncontrollable, as is the demand. Traditional design and optimization tools, developed for controlled power
sources, cannot be employed here. Simulation methods seem to be the best solution.
The dynamic model of the proposed system is first elaborated in the stationary reference frame and
then transformed into the synchronous orthogonal reference frame. The transformed variables are used in
control of the voltage source converter as the heart of the interfacing system between DG resources and utility
grid. By setting an appropriate compensation current references from the sensed load currents in control circuit
loop of DG, the active, reactive, and harmonic load current components will be compensated with fast dynamic
response, thereby achieving sinusoidal grid currents in phase with load voltages, while required power of the
load is more than the maximum injected power of the DG to the grid. In addition, the proposed control method
of this paper does not need a phase-locked loop in control circuit and has fast dynamic response in providing
active and reactive power components of the grid-connected loads.
Decentralised PI controller design based on dynamic interaction decoupling in...IJECEIAES
An enhanced method for design of decenralised proportional integral (PI) controllers to control various variables of flotation columns is proposed. These columns are multivariable processes characterised by multiple interacting manipulated and controlled variables. The control of more than one variable is not an easy problem to solve as a change in a specific manipulated variable affects more than one controlled variable. Paper proposes an improved method for design of decentralized PI controllers through the introduction of decoupling of the interconnected model of the process. Decoupling the system model has proven to be an effective strategy to reduce the influence of the interactions in the closed-loop control and consistently to keep the system stable. The mathematical derivations and the algorithm of the design procedure are described in detail. The behaviour and performance of the closed-loop systems without and with the application of the decoupling method was investigated and compared through simulations in MATLAB/Simulink. The results show that the decouplers - based closedloop system has better performance than the closed-loop system without decouplers. The highest improvement (2 to 50 times) is in the steady-state error and 1.2 to 7 times in the settling and rising time. Controllers can easily be implemented.
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.
Design methodology of smart photovoltaic plant IJECEIAES
In this article, we present a new methodology to design an intelligent photovoltaic power plant connected to an electrical grid with storage to supply the laying hen rearing centers. This study requires a very competent design methodology in order to optimize the production and consumption of electrical energy. Our contribution consists in proposing a robust dimensioning synthesis elaborated according to a data flow chart. To achieve this objective, the photovoltaic system was first designed using a deterministic method, then the software "Homer" was used to check the feasibility of the design. Then, controllers (fuzzy logic) were used to optimize the energy produced and consumed. The power produced by the photovoltaic generator (GPV) is optimized by two fuzzy controllers: one to extract the maximum energy and another to control the batteries. The energy consumed by the load is optimized by a fuzzy controller that regulates the internal climate of the livestock buildings. The proposed control strategies are developed and implemented using MATLAB/Simulink.
Frequency regulation service of multiple-areas vehicle to grid application in...IJECEIAES
Regarding a potential of electric vehicles, it has been widely discussed that the electric vehicle can be participated in electricity ancillary services. Among the ancillary service products, the system frequency regulation is often considered. However, the participation in this service has to be conformed to the hierarchical frequency control architecture. Therefore, the vehicle to grid (V2G) application in this article is proposed in the term of multiple-areas of operation. The multiple-areas in this article are concerned as parking areas, which the parking areas can be implied as a V2G operator. From that, V2G operator can obtain the control signal from hierarchical control architecture for power sharing purpose. A power sharing concept between areas is fulfilled by a proposed adaptive droop factor based on battery state of charge and available capacity of parking area. A nonlinear multiplier factor is used for the droop adaptation. An available capacity is also applied as a limitation for the V2G operation. The available capacity is analyzed through a stochastic character. As the V2G application has to be cooperated with the hierarchical control functions, i.e. primary control and secondary control, then the effect of V2G on hierarchical control functions is investigated and discussed.
Real Coded Genetic Algorithm Based Improvement of Efficiency in Interleaved B...IJPEDS-IAES
The reliability, efficiency, and controllability of Photo Voltaic power systems can be increased by embedding the components of a Boost Converter. Currently, the converter technology overcomes the main problems of manufacturing cost, efficiency and mass production. Issue to limit the life span of a Photo Voltaic inverter is the huge electrolytic capacitor across the Direct Current bus for energy decoupling. This paper presents a two-phase interleaved boost converter which ensures 180 angle phase shift between the two interleaved converters. The Proportional Integral controller is used to reshape that the controller attempts to minimize the error by adjusting the control inputs and also real coded genetic algorithm is proposed for tuning of controlling parameters of Proportional Integral controller. The real coded genetic algorithm is applied in the Interleaved Boost Converter with Advanced Pulse Width Modulation Techniques for improving the results of efficiency and reduction of ripple current. Simulation results illustrate the improvement of efficiency and the diminution of ripple current.
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.
Laboratory investigation of the impact of air pollution on partial discharge ...IJECEIAES
Studying the discharge characteristics of transmission line insulators in the presence of pollution, particularly when the contaminated layer is wet by rain, fog or condensation, is necessary for selecting the proper insulation. Therefore, identifying the major air pollutants as well as the most effective ones on the discharge performance of outdoor insulators is mandatory. A systematic approach has been proposed to evaluate the impact of dominant air pollutants of an area on partial discharge (P.D) inception voltage of specimen insulators. Based on the suggested method, determining the pollution constituents, defining the dominant pollutant of the area, finding the most commonly used insulators for medium and above distribution voltages within the geographical boundaries of the Central Province of Iran, as well as examining the effect of dominant air pollutant of the region on partial discharge inception voltage of designated insulators by laboratory measurements, are the necessary steps toward a comprehensive study of the subject.
The gravitational search algorithm for incorporating TCSC devices into the sy...IJECEIAES
This paper proposes a gravitational search algorithm (GSA) to allocate the thyristor-controlled series compensator (TCSC) incorporation with the issue of reactive power management. The aim of using TCSC units in this study is to minimize active and reactive power losses. Reserve beyond the thermal border, enhance the voltage profile and increase transmission-lines flow while continuing the whole generation cost of the system a little increase compared with its single goal base case. The optimal power flow (OPF) described is a consideration for finding the best size and location of the TCSCs devices seeing techno-economic subjects for minimizing fuel cost of generation units and the costs of installing TCSCs devices. The GSA algorithm's high ability in solving the proposed multi-objective problem is tested on two 9 and 30 bus test systems. For each test system, four case studies are considered to represent both normal and emergency operating conditions. The proposed GSA method's simulation results show that GSA offers a practical and robust highquality solution for the problem and improves system performance.
Due to the ever-increasing energy demand, power system operators have attempted to cope with these demands while keeping the power system remain operable. Economic constraints have forced the power system operator to abandon their effort in expanding the power system. The increased load demand can cause the power system to suffer from voltage instability and voltage collapse, especially during contingency condition. Hence, a strategy is required to maintain the steady state operation of a power system. Various research has been conducted to tackle this problem. Therefore, this paper presents the implementation of Chaos Embedded Symbiotic Organisms Search technique to solve optimal FACTS device allocation problem in power transmission system. Various practical constraints are also considered in the optimisation process to emulate the real-life constraints in power system. The optimisation process is conducted on a 26-bus IEEE RTS has validated that the results obtained has not violated the power system stability. The results provided by the proposed optimisation technique has successfully improved the voltage profile and voltage security in the system. Comparative studies are also conducted involving Particle Swarm Optimization and Evolutionary Programming technique resulting good results agreement and superiority of the proposed technique. Results obtained from this study would be beneficial to the power system operators regarding optimisation in power system operation for the implementation in real power transmission network.
Optimal Configuration of Wind Farms in Radial Distribution System Using Parti...journalBEEI
Recently, a wide range of wind farm based distributed generations (DGs) are being integrated into distribution systems to fulfill energy demands and to reduce the burden on transmission corridors. The non-optimal configuration of DGs could severely affect the distribution system operations and control. Hence, the aim of this paper is to analyze the wind data in order to build a mathematical model for power output and pinpoint the optimal location. The overall objective is minimization of power loss reduction in distribution system. The five years of wind data was taken from 24o 44’ 29” North, 67o 35’ 9” East coordinates in Pakistan. The optimal location for these wind farms were pinpointed via particle swarm optimization (PSO) algorithm using standard IEEE 33 radial distribution system. The result reveals that the proposed method helps in improving renewable energy near to load centers, reduce power losses and improve voltage profile of the system. Moreover, the validity and performance of the proposed model were also compared with other optimization algorithms.
Introducing LQR-fuzzy for a dynamic multi area LFC-DR modelIJECEIAES
It is well known that Load Frequency Control (LFC) model plays a vital role in electric power system design and operation. In the literature, much research works has stated on the advantages and realization of DR (Demand Response), which has proved to be an important part of the future smart grid. In an interconnected power system, if a load demand changes randomly, both frequency and tie line power varies. LFC-DR model is tuned by standard controllers like PI, PD, PID controllers, as they have constant gains. Hence, they are incapable of acquiring desirable dynamic performance for an extensive variety of operating conditions and various load changes. This paper presents the idea of introducing a DR control loop in the traditional Multi area LFC model (called LFC -DR) using LQR- Fuzzy Logic Control. The effect of DR-CDL i.e. (Demand Response Communication Delay Latency) in the design is also considered and is linearized using Padé approximation. Simulation results shows that the addition of DR control loop with proposed controller guarantees stability of the overall closed-loop LFC-DR system which effectively improves the system dynamic performance and is superior over a classical controller at different operating scenarios.
Network Reconfiguration in Distribution Systems Using Harmony Search AlgorithmIOSRJEEE
This manuscript explores feeder reconfiguration in distribution networks and presents an efficient method to optimize the radial distribution system by means of simultaneous reconfiguration. Network Reconfiguration of radial distribution system is a significant way of altering the power flow through the lines. This assessment presents a modern method to solve the network reconfiguration problem with an objective of minimizing real power loss and improving the voltage profile in radial distribution system (RDS). A precise and load flow algorithm is applied and the objective function is formulated to solve the problem which includes power loss minimization. HSA Algorithm is utilized to restructure and identify the optimal strap switches for minimization of real power loss in a distribution network.. The strategy has been tested on IEEE 33-bus and 69- bus systems to show the accomplishment and the adequacy of the proposed technique. The results demonstrate that a significant reduction in real power losses and improvement of voltage profiles.
An Adaptive Virtual Impedance Based Droop Control Scheme for Parallel Inverte...IAES-IJPEDS
This paper presents an adaptive virtual impedance based droop control
scheme for parallel inverter operation in low voltage microgrid. Because it is
essential to achieve power sharing between inverters in microgrid, various
droop control schemes have been proposed. In practice, the line impedance
between inverters and the point of common coupling (PCC) in microgrid are
not always equal. This imbalance in line impedance often results in a reactive
power mismatch among inverters. This problem has been solved by
introducing a virtual impedance loop in the conventional droop control
scheme. However, the reactive power sharing performance of this method is
still deteriorated when the line impedances change during operation. To
overcome such a problem, a new control scheme that is based on a virtual
impedance loop and an impedance estimation scheme is proposed.
To monitor the changes in line impedances, the impedance estimator is
implemented by using the output voltages and currents of inverters as well as
the voltages at the PCC. To compensate for the reactive power mismatch due
to the line impedance changes, the estimated line impedance is fed to the
virtual impedance loop in which it adjusts the virtual impedance value.
Comparative simulation results with the conventional ones verify the
effectiveness of the proposed adaptive virtual impedance based droop control
scheme.
Resource aware wind farm and D-STATCOM optimal sizing and placement in a dist...IJECEIAES
Doubly fed induction generators (DFIG) based wind farms are capable of providing reactive power compensation. Compensation capability enhancement using reactors such as distributed static synchronous compensator (D-STATCOM) while connecting distribution generation (DG) systems to grid is imperative. This paper presents an optimal placement and sizing of offshore wind farms in a coastal distribution system that is emulated on an IEEE 33 bus system. A multi-objective formulation for optimal placement and sizing of the offshore wind farms with both the location and size constraints is developed. Teaching learning algorithm is used to optimize the multi-objective function constraining on the capacity and location of the offshore wind farms. The proposed formulation is a multi-objective problem for placement of the wind generator in the power system with dynamic wind supply to the power system. The random wind speed is generated as the input and the wind farm output generated to perform the optimal sizing and placement in the distributed system. MATLAB based simulation developed is found to be efficient and robust.
A NOVEL CONTROL STRATEGY FOR POWER QUALITY IMPROVEMENT USING ANN TECHNIQUE FO...IJERD Editor
The proposed system presents power-control strategies of a Micro grid-connected hybrid generation
system with versatile power transfer. This hybrid system allows maximum utilization of freely available
renewable energy sources like wind and photovoltaic energies. For this, an adaptive MPPT algorithm along with
standard perturbs and observes method will be used for the system.
The inverter converts the DC output from non-conventional energy into useful AC power for the
connected load. This hybrid system operates under normal conditions which include normal room temperature
in the case of solar energy and normal wind speed at plain area in the case of wind energy. However, designing
an optimal micro grid is not an easy task, due to the fact that primary energy carriers are changeable and
uncontrollable, as is the demand. Traditional design and optimization tools, developed for controlled power
sources, cannot be employed here. Simulation methods seem to be the best solution.
The dynamic model of the proposed system is first elaborated in the stationary reference frame and
then transformed into the synchronous orthogonal reference frame. The transformed variables are used in
control of the voltage source converter as the heart of the interfacing system between DG resources and utility
grid. By setting an appropriate compensation current references from the sensed load currents in control circuit
loop of DG, the active, reactive, and harmonic load current components will be compensated with fast dynamic
response, thereby achieving sinusoidal grid currents in phase with load voltages, while required power of the
load is more than the maximum injected power of the DG to the grid. In addition, the proposed control method
of this paper does not need a phase-locked loop in control circuit and has fast dynamic response in providing
active and reactive power components of the grid-connected loads.
Decentralised PI controller design based on dynamic interaction decoupling in...IJECEIAES
An enhanced method for design of decenralised proportional integral (PI) controllers to control various variables of flotation columns is proposed. These columns are multivariable processes characterised by multiple interacting manipulated and controlled variables. The control of more than one variable is not an easy problem to solve as a change in a specific manipulated variable affects more than one controlled variable. Paper proposes an improved method for design of decentralized PI controllers through the introduction of decoupling of the interconnected model of the process. Decoupling the system model has proven to be an effective strategy to reduce the influence of the interactions in the closed-loop control and consistently to keep the system stable. The mathematical derivations and the algorithm of the design procedure are described in detail. The behaviour and performance of the closed-loop systems without and with the application of the decoupling method was investigated and compared through simulations in MATLAB/Simulink. The results show that the decouplers - based closedloop system has better performance than the closed-loop system without decouplers. The highest improvement (2 to 50 times) is in the steady-state error and 1.2 to 7 times in the settling and rising time. Controllers can easily be implemented.
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.
Design methodology of smart photovoltaic plant IJECEIAES
In this article, we present a new methodology to design an intelligent photovoltaic power plant connected to an electrical grid with storage to supply the laying hen rearing centers. This study requires a very competent design methodology in order to optimize the production and consumption of electrical energy. Our contribution consists in proposing a robust dimensioning synthesis elaborated according to a data flow chart. To achieve this objective, the photovoltaic system was first designed using a deterministic method, then the software "Homer" was used to check the feasibility of the design. Then, controllers (fuzzy logic) were used to optimize the energy produced and consumed. The power produced by the photovoltaic generator (GPV) is optimized by two fuzzy controllers: one to extract the maximum energy and another to control the batteries. The energy consumed by the load is optimized by a fuzzy controller that regulates the internal climate of the livestock buildings. The proposed control strategies are developed and implemented using MATLAB/Simulink.
Frequency regulation service of multiple-areas vehicle to grid application in...IJECEIAES
Regarding a potential of electric vehicles, it has been widely discussed that the electric vehicle can be participated in electricity ancillary services. Among the ancillary service products, the system frequency regulation is often considered. However, the participation in this service has to be conformed to the hierarchical frequency control architecture. Therefore, the vehicle to grid (V2G) application in this article is proposed in the term of multiple-areas of operation. The multiple-areas in this article are concerned as parking areas, which the parking areas can be implied as a V2G operator. From that, V2G operator can obtain the control signal from hierarchical control architecture for power sharing purpose. A power sharing concept between areas is fulfilled by a proposed adaptive droop factor based on battery state of charge and available capacity of parking area. A nonlinear multiplier factor is used for the droop adaptation. An available capacity is also applied as a limitation for the V2G operation. The available capacity is analyzed through a stochastic character. As the V2G application has to be cooperated with the hierarchical control functions, i.e. primary control and secondary control, then the effect of V2G on hierarchical control functions is investigated and discussed.
Real Coded Genetic Algorithm Based Improvement of Efficiency in Interleaved B...IJPEDS-IAES
The reliability, efficiency, and controllability of Photo Voltaic power systems can be increased by embedding the components of a Boost Converter. Currently, the converter technology overcomes the main problems of manufacturing cost, efficiency and mass production. Issue to limit the life span of a Photo Voltaic inverter is the huge electrolytic capacitor across the Direct Current bus for energy decoupling. This paper presents a two-phase interleaved boost converter which ensures 180 angle phase shift between the two interleaved converters. The Proportional Integral controller is used to reshape that the controller attempts to minimize the error by adjusting the control inputs and also real coded genetic algorithm is proposed for tuning of controlling parameters of Proportional Integral controller. The real coded genetic algorithm is applied in the Interleaved Boost Converter with Advanced Pulse Width Modulation Techniques for improving the results of efficiency and reduction of ripple current. Simulation results illustrate the improvement of efficiency and the diminution of ripple current.
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.
Laboratory investigation of the impact of air pollution on partial discharge ...IJECEIAES
Studying the discharge characteristics of transmission line insulators in the presence of pollution, particularly when the contaminated layer is wet by rain, fog or condensation, is necessary for selecting the proper insulation. Therefore, identifying the major air pollutants as well as the most effective ones on the discharge performance of outdoor insulators is mandatory. A systematic approach has been proposed to evaluate the impact of dominant air pollutants of an area on partial discharge (P.D) inception voltage of specimen insulators. Based on the suggested method, determining the pollution constituents, defining the dominant pollutant of the area, finding the most commonly used insulators for medium and above distribution voltages within the geographical boundaries of the Central Province of Iran, as well as examining the effect of dominant air pollutant of the region on partial discharge inception voltage of designated insulators by laboratory measurements, are the necessary steps toward a comprehensive study of the subject.
The gravitational search algorithm for incorporating TCSC devices into the sy...IJECEIAES
This paper proposes a gravitational search algorithm (GSA) to allocate the thyristor-controlled series compensator (TCSC) incorporation with the issue of reactive power management. The aim of using TCSC units in this study is to minimize active and reactive power losses. Reserve beyond the thermal border, enhance the voltage profile and increase transmission-lines flow while continuing the whole generation cost of the system a little increase compared with its single goal base case. The optimal power flow (OPF) described is a consideration for finding the best size and location of the TCSCs devices seeing techno-economic subjects for minimizing fuel cost of generation units and the costs of installing TCSCs devices. The GSA algorithm's high ability in solving the proposed multi-objective problem is tested on two 9 and 30 bus test systems. For each test system, four case studies are considered to represent both normal and emergency operating conditions. The proposed GSA method's simulation results show that GSA offers a practical and robust highquality solution for the problem and improves system performance.
Due to the ever-increasing energy demand, power system operators have attempted to cope with these demands while keeping the power system remain operable. Economic constraints have forced the power system operator to abandon their effort in expanding the power system. The increased load demand can cause the power system to suffer from voltage instability and voltage collapse, especially during contingency condition. Hence, a strategy is required to maintain the steady state operation of a power system. Various research has been conducted to tackle this problem. Therefore, this paper presents the implementation of Chaos Embedded Symbiotic Organisms Search technique to solve optimal FACTS device allocation problem in power transmission system. Various practical constraints are also considered in the optimisation process to emulate the real-life constraints in power system. The optimisation process is conducted on a 26-bus IEEE RTS has validated that the results obtained has not violated the power system stability. The results provided by the proposed optimisation technique has successfully improved the voltage profile and voltage security in the system. Comparative studies are also conducted involving Particle Swarm Optimization and Evolutionary Programming technique resulting good results agreement and superiority of the proposed technique. Results obtained from this study would be beneficial to the power system operators regarding optimisation in power system operation for the implementation in real power transmission network.
Optimal Configuration of Wind Farms in Radial Distribution System Using Parti...journalBEEI
Recently, a wide range of wind farm based distributed generations (DGs) are being integrated into distribution systems to fulfill energy demands and to reduce the burden on transmission corridors. The non-optimal configuration of DGs could severely affect the distribution system operations and control. Hence, the aim of this paper is to analyze the wind data in order to build a mathematical model for power output and pinpoint the optimal location. The overall objective is minimization of power loss reduction in distribution system. The five years of wind data was taken from 24o 44’ 29” North, 67o 35’ 9” East coordinates in Pakistan. The optimal location for these wind farms were pinpointed via particle swarm optimization (PSO) algorithm using standard IEEE 33 radial distribution system. The result reveals that the proposed method helps in improving renewable energy near to load centers, reduce power losses and improve voltage profile of the system. Moreover, the validity and performance of the proposed model were also compared with other optimization algorithms.
Introducing LQR-fuzzy for a dynamic multi area LFC-DR modelIJECEIAES
It is well known that Load Frequency Control (LFC) model plays a vital role in electric power system design and operation. In the literature, much research works has stated on the advantages and realization of DR (Demand Response), which has proved to be an important part of the future smart grid. In an interconnected power system, if a load demand changes randomly, both frequency and tie line power varies. LFC-DR model is tuned by standard controllers like PI, PD, PID controllers, as they have constant gains. Hence, they are incapable of acquiring desirable dynamic performance for an extensive variety of operating conditions and various load changes. This paper presents the idea of introducing a DR control loop in the traditional Multi area LFC model (called LFC -DR) using LQR- Fuzzy Logic Control. The effect of DR-CDL i.e. (Demand Response Communication Delay Latency) in the design is also considered and is linearized using Padé approximation. Simulation results shows that the addition of DR control loop with proposed controller guarantees stability of the overall closed-loop LFC-DR system which effectively improves the system dynamic performance and is superior over a classical controller at different operating scenarios.
Network Reconfiguration in Distribution Systems Using Harmony Search AlgorithmIOSRJEEE
This manuscript explores feeder reconfiguration in distribution networks and presents an efficient method to optimize the radial distribution system by means of simultaneous reconfiguration. Network Reconfiguration of radial distribution system is a significant way of altering the power flow through the lines. This assessment presents a modern method to solve the network reconfiguration problem with an objective of minimizing real power loss and improving the voltage profile in radial distribution system (RDS). A precise and load flow algorithm is applied and the objective function is formulated to solve the problem which includes power loss minimization. HSA Algorithm is utilized to restructure and identify the optimal strap switches for minimization of real power loss in a distribution network.. The strategy has been tested on IEEE 33-bus and 69- bus systems to show the accomplishment and the adequacy of the proposed technique. The results demonstrate that a significant reduction in real power losses and improvement of voltage profiles.
An Adaptive Virtual Impedance Based Droop Control Scheme for Parallel Inverte...IAES-IJPEDS
This paper presents an adaptive virtual impedance based droop control
scheme for parallel inverter operation in low voltage microgrid. Because it is
essential to achieve power sharing between inverters in microgrid, various
droop control schemes have been proposed. In practice, the line impedance
between inverters and the point of common coupling (PCC) in microgrid are
not always equal. This imbalance in line impedance often results in a reactive
power mismatch among inverters. This problem has been solved by
introducing a virtual impedance loop in the conventional droop control
scheme. However, the reactive power sharing performance of this method is
still deteriorated when the line impedances change during operation. To
overcome such a problem, a new control scheme that is based on a virtual
impedance loop and an impedance estimation scheme is proposed.
To monitor the changes in line impedances, the impedance estimator is
implemented by using the output voltages and currents of inverters as well as
the voltages at the PCC. To compensate for the reactive power mismatch due
to the line impedance changes, the estimated line impedance is fed to the
virtual impedance loop in which it adjusts the virtual impedance value.
Comparative simulation results with the conventional ones verify the
effectiveness of the proposed adaptive virtual impedance based droop control
scheme.
Distributed Generation Allocation to Improve Steady State Voltage Stability o...IJAPEJOURNAL
In this paper, a new method is proposed to optimal distributed generation allocation for stability enhancement in radial distribution networks. Voltage stability is related with stable load and acceptable voltage in all buses of system. According to the time spectrum of the incident of the phenomena the instability is divided into steady state and transient voltage instability. The analysis is accomplished using a steady state voltage stability index which can be evaluated at each node of the distribution system. Different optimal locations and capacities are used to check this effect. The location of DG is more important in comparison with the capacities and has the main effect on the network voltage stability. Effects of capacity and location on increasing steady state voltage stability in radial distribution networks are evaluated through Imperialist Competitive Algorithm (ICA) and at the end the results are compared to particle swarm optimization and genetic algorithm on the terms of speed, accuracy and convergence.
Loss issue is significant in power system since it affects the operation of power system, which ultimately can be translated to monetary effect. Incremental demand that explicitly adding the reactive load causes extra heating losses in the transmission circuit. Without appropriate remedial control, the temperature increase on transmission line cable would end with insulation failure. This phenomenon can be alleviated with a proper compensation scheme that provides optimal solution along with avoidance of under-compensation or over-compensation. Evolutionary Programming (EP) has been recognised as one of the powerful optimisation technique, applied in solving power system problems. Nevertheless, EP is an old technique that sometimes could reach to a settlement that is not fully satisfied. Thus, the need fora new approach to improve the setback is urgent. This paper presents immunized-evolutionary algorithm based technique for loss control in transmission system with multi-load increment. The classical EP was integrated with immune algorithm so as to reduce the computational burden experienced by the classical EP.The algorithm has been tested on an IEEE 12-Bus System and IEEE 14-Bus System.Comparative study was conducted between EP and IEP in terms of optimisation performance. The optimal size and location of PV determined by IEP was able to control the loss in transmission system when the load increases. Results obtained from the studies revealed the merit of the proposed IEP; indicating its feasibility for future implementation in practical system.
Cost Aware Expansion Planning with Renewable DGs using Particle Swarm Optimiz...IJERA Editor
This Paper is an attempt to develop the expansion-planning algorithm using meta heuristics algorithms. Expansion Planning is always needed as the power demand is increasing every now and then. Thus for a better expansion planning the meta heuristic methods are needed. The cost efficient Expansion planning is desired in the proposed work. Recently distributed generation is widely researched to implement in future energy needs as it is pollution free and capability of installing it in rural places. In this paper, optimal distributed generation expansion planning with Particle Swarm Optimization (PSO) and Cuckoo Search Algorithm (CSA) for identifying the location, size and type of distributed generator for future demand is predicted with lowest cost as the constraints. Here the objective function is to minimize the total cost including installation and operating cost of the renewable DGs. MATLAB based `simulation using M-file program is used for the implementation and Indian distribution system is used for testing the results.
Dual techniques of load shedding and capacitor placement considering load mo...IJECEIAES
Voltage stability represents one of the main issues in electrical power system. Under voltage load shedding (UVLS) has long been regarded as one of the most successful techniques to prevent the voltage collapse. However, the ordinary load shedding schemes do not consider the different load models and decreasing in the economic cost that resulted from load disconnection, so the dual techniques of load shedding with reactive compensation are needed. Usually loads being modeled as constant power, while in fact of load flow the various load models are utilized. An investigation of optimal dual load shedding with reactive compensation for distribution system based on direct backward forward sweep method (DBFSM) load flow along with a comparison among the other load models are presented in this paper. The teaching learning-based optimization (TLBO) algorithm is executed in order to reduce power losses and enhance the voltage profile. This algorithm is tested and applied to IEEE-16 bus distribution test system to find the optimal superior capacitor size and placement while minimizing load shading for the network. Five different load shedding sequences are considered and the optimization performance of load models demonstrated the comparison through MATLAB program.
Maximum power point tracking and space vector modulation control of quasi-z-s...IJECEIAES
The quasi-Z-source inverter (qZSI) become one of the most promising power electronic converters for photovoltaic (PV) applications, due to its capability to perform a buck-boost conversion of the input voltage in a single stage. The control strategy based maximum power point tracking (MPPT) and proportional integral (PI) controller are well known in grid-connected with traditional configuration but not in qZSI. This paper presents a control strategy for qZSI grid-connected based on the MPPT algorithm and the linear control by PI controllers. This is complemented by the capability to efficiently transfer the harvested power to the grid, ensuring a unity power factor. The proposed control strategy effectively separates the control mechanisms for the direct current (DC) and alternating current (AC) sides by utilizing the two control variables, the shoot-through duty ratio and the modulation index. An adapted space vector modulation technique is then utilized to generate the switching pulse width modulation (PWM) signals, using these two control variables as inputs. The proposed approach was tested and validated under MATLAB/Simulink and PLECS software.
Optimal Siting of Distributed Generators in a Distribution Network using Arti...IJECEIAES
Distributed generation (DG) sources are being installed in distribution networks worldwide due to their numerous advantages over the conventional sources which include operational and economical benefits. Random placement of DG sources in a distribution network will result in adverse effects such as increased power loss, loss of voltage stability and reliability, increase in operational costs, power quality issues etc. This paper presents a methodology to obtain the optimal location for the placement of multiple DG sources in a distribution network from a technical perspective. Optimal location is obtained by evaluating a global multi-objective technical index (MOTI) using a weighted sum method. Clonal selection based artificial immune system (AIS) is used along with optimal power flow (OPF) technique to obtain the solution. The proposed method is executed on a standard IEEE-33 bus radial distribution system. The results justify the choice of AIS and the use of MOTI in optimal siting of DG sources which improves the distribution system efficiency to a great extent in terms of reduced real and reactive power losses, improved voltage profile and voltage stability. Solutions obtained using AIS are compared with Genetic algorithm (GA) and Particle Swarm optimization (PSO) solutions for the same objective function.
Enhancing of single-stage grid-connected photovoltaic system using fuzzy logi...IJECEIAES
The power generated by photovoltaic (PV) systems is influenced by
environmental factors. This variability hampers the control and utilization of
solar cells' peak output. In this study, a single-stage grid-connected PV
system is designed to enhance power quality. Our approach employs fuzzy
logic in the direct power control (DPC) of a three-phase voltage source
inverter (VSI), enabling seamless integration of the PV connected to the
grid. Additionally, a fuzzy logic-based maximum power point tracking
(MPPT) controller is adopted, which outperforms traditional methods like
incremental conductance (INC) in enhancing solar cell efficiency and
minimizing the response time. Moreover, the inverter's real-time active and
reactive power is directly managed to achieve a unity power factor (UPF).
The system's performance is assessed through MATLAB/Simulink
implementation, showing marked improvement over conventional methods,
particularly in steady-state and varying weather conditions. For solar
irradiances of 500 and 1,000 W/m2
, the results show that the proposed
method reduces the total harmonic distortion (THD) of the injected current
to the grid by approximately 46% and 38% compared to conventional
methods, respectively. Furthermore, we compare the simulation results with
IEEE standards to evaluate the system's grid compatibility.
The high penetration of fluctuated photovoltaic (PV) output power into utility grid system will affect the operation of interconnected grids. The unnecessary output power fluctuation of PV system is contributed by unpredictable nature and inconsistency of solar irradiance and temperature. This paper presents a control scheme to mitigate the output power fluctuations from PV system and dispatch out the constant power on an hourly basis to the utility grid. In this regards, battery energy storage (BES) system is used to eliminate the output power fluctuation. Control scheme is proposed to maintain parameters of BES within required operating constraints. The effectiveness of the proposed control scheme is tested using historical PV system input data obtained from a site in Malaysia. The simulation results show that the proposed control scheme of BES system can properly manage the output power fluctuations of the PV sources by dispatching the output on hourly basis to the utility grid while meeting all required operating constraints.
A new linear quadratic regulator model to mitigate frequency disturbances in...IJECEIAES
This paper proposes a new model integrating a linear quadratic regulator (LQR) controller to mitigate frequency disturbances in the power system during cyber-attack, called as linear quadratic regulator to mitigate frequency disturbances (LQRMFD). As we know, most of the existing models have a common problem with achieving significant performances in mitigating dynamic response parameters, such as frequency deviation and settling time. However, the key aspect of LQRMFD is to mitigate the above issues with remarkable performance improvements. An uncommon and stable power system model has been considered in LQRMFD first to reach such a goal. A numerical problem has been solved to derive a certain characteristic equation, where the Routh-Hurwitz array criterion is applied for determining the stability of such a power system. After that, a state-space equation is developed from the power system to activate the LQR controller. Thus, achieving diversity and eliminating the redundancy of the power system considered can be obtained in LQRMFD. To evaluate the performance of LQRMFD, a series of experiments was conducted using the MATLABSimulink tool. Rigorous comparisons were also made among the results of LQRMFD, self-implemented and existing models. Furthermore, a detailed analysis was reported among those models to find the performance improvement of LQRMFD in percentage.
Reliability Constrained Unit Commitment Considering the Effect of DG and DR P...IJECEIAES
Due to increase in energy prices at peak periods and increase in fuel cost, involving Distributed Generation (DG) and consumption management by Demand Response (DR) will be unavoidable options for optimal system operations. Also, with high penetration of DGs and DR programs into power system operation, the reliability criterion is taken into account as one of the most important concerns of system operators in management of power system. In this paper, a Reliability Constrained Unit Commitment (RCUC) at presence of time-based DR program and DGs integrated with conventional units is proposed and executed to reach a reliable and economic operation. Designated cost function has been minimized considering reliability constraint in prevailing UC formulation. The UC scheduling is accomplished in short-term so that the reliability is maintained in acceptable level. Because of complex nature of RCUC problem and full AC load flow constraints, the hybrid algorithm included Simulated Annealing (SA) and Binary Particle Swarm Optimization (BPSO) has been proposed to optimize the problem. Numerical results demonstrate the effectiveness of the proposed method and considerable efficacy of the time-based DR program in reducing operational costs by implementing it on IEEE-RTS79.
An approach for a multi-stage under-frequency based load shedding scheme for...IJECEIAES
The integration of load shedding schemes with mainstream protection in power system networks is vital. The traditional power system network incorporates different protection schemes to protect its components. Once the power network reaches its maximum limits, and the load demand continue to increase the whole system will experience power system instability. The system frequency usually drops due to the loss of substantial generation creating imbalance. The best method to recover the system from instability is by introducing an under-frequency load shedding (UFLS) scheme in parallel with the protection schemes. This paper proposed a new UFLS scheme used in power systems and industry to maintain stability. Three case studies were implemented in this paper. Multi-stage decisionmaking algorithms load shedding in the environment of the DIgSILENT power factory platform is developed. The proposed algorithm speeds-up the operation of the UFLS scheme. The load shedding algorithm of the proposed scheme is implemented as a systematic process to achieve stability of the power network which is exposed to different operating conditions. The flexibility of the proposed scheme is validated with the modified IEEE 39-bus New England model. The application of the proposed novel UFLS schemes will contribute further to the development of new types of engineers.
In our homes or offices, security has been a vital issue. Control of home security system remotely always offers huge advantages like the arming or disarming of the alarms, video monitoring, and energy management control apart from safeguarding the home free up intruders. Considering the oldest simple methods of security that is the mechanical lock system that has a key as the authentication element, then an upgrade to a universal type, and now unique codes for the lock. The recent advancement in the communication system has brought the tremendous application of communication gadgets into our various areas of life. This work is a real-time smart doorbell notification system for home Security as opposes of the traditional security methods, it is composed of the doorbell interfaced with GSM Module, a GSM module would be triggered to send an SMS to the house owner by pressing the doorbell, the owner will respond to the guest by pressing a button to open the door, otherwise, a message would be displayed to the guest for appropriate action. Then, the keypad is provided for an authorized person for the provision of password for door unlocking, if multiple wrong password attempts were made to unlock, a message of burglary attempt would be sent to the house owner for prompt action. The main benefit of this system is the uniqueness of the incorporation of the password and messaging systems which denies access to any unauthorized personality and owner's awareness method.
Augmented reality, the new age technology, has widespread applications in every field imaginable. This technology has proven to be an inflection point in numerous verticals, improving lives and improving performance. In this paper, we explore the various possible applications of Augmented Reality (AR) in the field of Medicine. The objective of using AR in medicine or generally in any field is the fact that, AR helps in motivating the user, making sessions interactive and assist in faster learning. In this paper, we discuss about the applicability of AR in the field of medical diagnosis. Augmented reality technology reinforces remote collaboration, allowing doctors to diagnose patients from a different locality. Additionally, we believe that a much more pronounced effect can be achieved by bringing together the cutting edge technology of AR and the lifesaving field of Medical sciences. AR is a mechanism that could be applied in the learning process too. Similarly, virtual reality could be used in the field where more of practical experience is needed such as driving, sports, neonatal care training.
Image fusion is a sub field of image processing in which more than one images are fused to create an image where all the objects are in focus. The process of image fusion is performed for multi-sensor and multi-focus images of the same scene. Multi-sensor images of the same scene are captured by different sensors whereas multi-focus images are captured by the same sensor. In multi-focus images, the objects in the scene which are closer to the camera are in focus and the farther objects get blurred. Contrary to it, when the farther objects are focused then closer objects get blurred in the image. To achieve an image where all the objects are in focus, the process of images fusion is performed either in spatial domain or in transformed domain. In recent times, the applications of image processing have grown immensely. Usually due to limited depth of field of optical lenses especially with greater focal length, it becomes impossible to obtain an image where all the objects are in focus. Thus, it plays an important role to perform other tasks of image processing such as image segmentation, edge detection, stereo matching and image enhancement. Hence, a novel feature-level multi-focus image fusion technique has been proposed which fuses multi-focus images. Thus, the results of extensive experimentation performed to highlight the efficiency and utility of the proposed technique is presented. The proposed work further explores comparison between fuzzy based image fusion and neuro fuzzy fusion technique along with quality evaluation indices.
Graphs have become the dominant life-form of many tasks as they advance a
structure to represent many tasks and the corresponding relations. A powerful
role of networks/graphs is to bridge local feats that exist in vertices as they
blossom into patterns that help explain how nodal relations and their edges
impacts a complex effect that ripple via a graph. User cluster are formed as a
result of interactions between entities. Many users can hardly categorize their
contact into groups today such as “family”, “friends”, “colleagues” etc. Thus,
the need to analyze such user social graph via implicit clusters, enables the
dynamism in contact management. Study seeks to implement this dynamism
via a comparative study of deep neural network and friend suggest algorithm.
We analyze a user’s implicit social graph and seek to automatically create
custom contact groups using metrics that classify such contacts based on a
user’s affinity to contacts. Experimental results demonstrate the importance
of both the implicit group relationships and the interaction-based affinity in
suggesting friends.
This paper projects Gryllidae Optimization Algorithm (GOA) has been applied to solve optimal reactive power problem. Proposed GOA approach is based on the chirping characteristics of Gryllidae. In common, male Gryllidae chirp, on the other hand some female Gryllidae also do as well. Male Gryllidae draw the females by this sound which they produce. Moreover, they caution the other Gryllidae against dangers with this sound. The hearing organs of the Gryllidae are housed in an expansion of their forelegs. Through this, they bias to the produced fluttering sounds. Proposed Gryllidae Optimization Algorithm (GOA) has been tested in standard IEEE 14, 30 bus test systems and simulation results show that the projected algorithms reduced the real power loss considerably.
In the wake of the sudden replacement of wood and kerosene by gas cookers for several purposes in Nigeria, gas leakage has caused several damages in our homes, Laboratories among others. installation of a gas leakage detection device was globally inspired to eliminate accidents related to gas leakage. We present an alternative approach to developing a device that can automatically detect and control gas leakages and also monitor temperature. The system detects the leakage of the LPG (Liquefied Petroleum Gas) using a gas sensor, then triggred the control system response which employs ventilator system, Mobile phone alert and alarm when the LPG concentration in the air exceeds a certain level. The performance of two gas sensors (MQ5 and MQ6) were tested for a guided decision. Also, when the temperature of the environment poses a danger, LED (indicator), buzzer and LCD (16x2) display was used to indicate temperature and gas leakage status in degree Celsius and PPM respectively. Attension was given to the response time of the control system, which was ascertained that this system significantly increases the chances and efficiency of eliminating gas leakage related accident.
Feature selection problem is one of the main important problems in the text and data mining domain. This paper presents a comparative study of feature selection methods for Arabic text classification. Five of the feature selection methods were selected: ICHI square, CHI square, Information Gain, Mutual Information and Wrapper. It was tested with five classification algorithms: Bayes Net, Naive Bayes, Random Forest, Decision Tree and Artificial Neural Networks. In addition, Data Collection was used in Arabic consisting of 9055 documents, which were compared by four criteria: Precision, Recall, F-measure and Time to build model. The results showed that the improved ICHI feature selection got almost all the best results in comparison with other methods.
In this paper Gentoo Penguin Algorithm (GPA) is proposed to solve optimal reactive power problem. Gentoo Penguins preliminary population possesses heat radiation and magnetizes each other by absorption coefficient. Gentoo Penguins will move towards further penguins which possesses low cost (elevated heat concentration) of absorption. Cost is defined by the heat concentration, distance. Gentoo Penguins penguin attraction value is calculated by the amount of heat prevailed between two Gentoo penguins. Gentoo Penguins heat radiation is measured as linear. Less heat is received in longer distance, in little distance, huge heat is received. Gentoo Penguin Algorithm has been tested in standard IEEE 57 bus test system and simulation results show the projected algorithm reduced the real power loss considerably.
08 20272 academic insight on applicationIAESIJEECS
This research has thrown up many questions in need of further investigation.There was an expressive quantitative-qualitative research, which a common investigation form was used in.The dialogue item was also applied to discover if the contributors asserted the media-based attitude supplements their learning of academic English writing classes or not.Data recounted academic” insights toward using Skype as a sustaining implement for lessons releasing based on chosen variables: their occupation, year of education, and knowledge with Skype discovered that there were no important statistical differences in the use of Skype units because of medical academics major knowledge. There are statistically important differences in using Skype units. The findings also, disclosed that there are statistically significant differences in using Skype units due to the practice with Skype variable, in favors of academics with no Skype use practice. Skype instrument as an instructive media is a positive medium to be employed to supply academic medical writing data and assist education. Academics who do not have enough time to contribute in classes believe comfortable using the Skype-based attitude in scientific writing. They who took part in the course claimed that their approval of this media is due to learning academic innovative medical writing.
Cloud computing has sweeping impact on the human productivity. Today it’s used for Computing, Storage, Predictions and Intelligent Decision Making, among others. Intelligent Decision-Making using Machine Learning has pushed for the Cloud Services to be even more fast, robust and accurate. Security remains one of the major concerns which affect the cloud computing growth however there exist various research challenges in cloud computing adoption such as lack of well managed service level agreement (SLA), frequent disconnections, resource scarcity, interoperability, privacy, and reliability. Tremendous amount of work still needs to be done to explore the security challenges arising due to widespread usage of cloud deployment using Containers. We also discuss Impact of Cloud Computing and Cloud Standards. Hence in this research paper, a detailed survey of cloud computing, concepts, architectural principles, key services, and implementation, design and deployment challenges of cloud computing are discussed in detail and important future research directions in the era of Machine Learning and Data Science have been identified.
Notary is an official authorized to make an authentic deed regarding all deeds, agreements and stipulations required by a general rule. Activities carried out at the notary office such as recording client data and file data still use traditional systems that tend to be manual. The problem that occurs is the inefficiency in data processing and providing information to clients. Clients have difficulty getting information related to the progress of documents that are being taken care of at the notary's office. The client must take the time to arrive to the notary's office repeatedly to check the progress of the work of the document file. The purpose of this study is to facilitate clients in obtaining information about the progress of the work in progress, and make it easier for employees to process incoming documents by implementing an administrative system. This system was developed with the waterfall system development method and uses the Multi-Channel Access Technology integrated in the website to simplify the process of delivering information and requesting information from clients and to clients with Telegram and SMS Gateway. Clients will come to the office only when there is a notification from the system via Telegram or SMS notifying that the client must come directly to the notary's office, thus leading to an efficient time and avoiding excessive transportation costs. The overall functional system can function properly based on the results of alpha testing. The results of beta testing conducted by distributing the system feasibility test questionnaire to end users, get a percentage of 96% of users agree the system is feasible to be implemented.
In this work Tundra wolf algorithm (TWA) is proposed to solve the optimal reactive power problem. In the projected Tundra wolf algorithm (TWA) in order to avoid the searching agents from trapping into the local optimal the converging towards global optimal is divided based on two different conditions. In the proposed Tundra wolf algorithm (TWA) omega tundra wolf has been taken as searching agent as an alternative of indebted to pursue the first three most excellent candidates. Escalating the searching agents’ numbers will perk up the exploration capability of the Tundra wolf wolves in an extensive range. Proposed Tundra wolf algorithm (TWA) has been tested in standard IEEE 14, 30 bus test systems and simulation results show the proposed algorithm reduced the real power loss effectively.
In this work Predestination of Particles Wavering Search (PPS) algorithm has been applied to solve optimal reactive power problem. PPS algorithm has been modeled based on the motion of the particles in the exploration space. Normally the movement of the particle is based on gradient and swarming motion. Particles are permitted to progress in steady velocity in gradient-based progress, but when the outcome is poor when compared to previous upshot, immediately particle rapidity will be upturned with semi of the magnitude and it will help to reach local optimal solution and it is expressed as wavering movement. In standard IEEE 14, 30, 57,118,300 bus systems Proposed Predestination of Particles Wavering Search (PPS) algorithm is evaluated and simulation results show the PPS reduced the power loss efficiently.
In this paper, Mine Blast Algorithm (MBA) has been intermingled with Harmony Search (HS) algorithm for solving optimal reactive power dispatch problem. MBA is based on explosion of landmines and HS is based on Creativeness progression of musicians-both are hybridized to solve the problem. In MBA Initial distance of shrapnel pieces are reduced gradually to allow the mine bombs search the probable global minimum location in order to amplify the global explore capability. Harmony search (HS) imitates the music creativity process where the musicians supervise their instruments’ pitch by searching for a best state of harmony. Hybridization of Mine Blast Algorithm with Harmony Search algorithm (MH) improves the search effectively in the solution space. Mine blast algorithm improves the exploration and harmony search algorithm augments the exploitation. At first the proposed algorithm starts with exploration & gradually it moves to the phase of exploitation. Proposed Hybridized Mine Blast Algorithm with Harmony Search algorithm (MH) has been tested on standard IEEE 14, 300 bus test systems. Real power loss has been reduced considerably by the proposed algorithm. Then Hybridized Mine Blast Algorithm with Harmony Search algorithm (MH) tested in IEEE 30, bus system (with considering voltage stability index)- real power loss minimization, voltage deviation minimization, and voltage stability index enhancement has been attained.
Artificial Neural Networks have proved their efficiency in a large number of research domains. In this paper, we have applied Artificial Neural Networks on Arabic text to prove correct language modeling, text generation, and missing text prediction. In one hand, we have adapted Recurrent Neural Networks architectures to model Arabic language in order to generate correct Arabic sequences. In the other hand, Convolutional Neural Networks have been parameterized, basing on some specific features of Arabic, to predict missing text in Arabic documents. We have demonstrated the power of our adapted models in generating and predicting correct Arabic text comparing to the standard model. The model had been trained and tested on known free Arabic datasets. Results have been promising with sufficient accuracy.
In the present-day communications speech signals get contaminated due to
various sorts of noises that degrade the speech quality and adversely impacts
speech recognition performance. To overcome these issues, a novel approach
for speech enhancement using Modified Wiener filtering is developed and
power spectrum computation is applied for degraded signal to obtain the
noise characteristics from a noisy spectrum. In next phase, MMSE technique
is applied where Gaussian distribution of each signal i.e. original and noisy
signal is analyzed. The Gaussian distribution provides spectrum estimation
and spectral coefficient parameters which can be used for probabilistic model
formulation. Moreover, a-priori-SNR computation is also incorporated for
coefficient updation and noise presence estimation which operates similar to
the conventional VAD. However, conventional VAD scheme is based on the
hard threshold which is not capable to derive satisfactory performance and a
soft-decision based threshold is developed for improving the performance of
speech enhancement. An extensive simulation study is carried out using
MATLAB simulation tool on NOIZEUS speech database and a comparative
study is presented where proposed approach is proved better in comparison
with existing technique.
Previous research work has highlighted that neuro-signals of Alzheimer’s disease patients are least complex and have low synchronization as compared to that of healthy and normal subjects. The changes in EEG signals of Alzheimer’s subjects start at early stage but are not clinically observed and detected. To detect these abnormalities, three synchrony measures and wavelet-based features have been computed and studied on experimental database. After computing these synchrony measures and wavelet features, it is observed that Phase Synchrony and Coherence based features are able to distinguish between Alzheimer’s disease patients and healthy subjects. Support Vector Machine classifier is used for classification giving 94% accuracy on experimental database used. Combining, these synchrony features and other such relevant features can yield a reliable system for diagnosing the Alzheimer’s disease.
Attenuation correction designed for PET/MR hybrid imaging frameworks along with portion making arrangements used for MR-based radiation treatment remain testing because of lacking high-energy photon weakening data. We present a new method so as to uses the learned nonlinear neighborhood descriptors also highlight coordinating toward foresee pseudo-CT pictures starting T1w along with T2w MRI information. The nonlinear neighborhood descriptors are acquired through anticipating the direct descriptors interested in the nonlinear high-dimensional space utilizing an unequivocal constituent guide also low-position guess through regulated complex regularization. The nearby neighbors of every near descriptor inside the data MR pictures are looked during an obliged spatial extent of the MR pictures among the training dataset. By that point, the pseudo-CT patches are evaluated through k-closest neighbor relapse. The planned procedure designed for pseudo-CT forecast is quantitatively broke downward on top of a dataset comprising of coordinated mind MRI along with CT pictures on or after 13 subjects.
The cognitive radio prototype performance is to alleviate the scarcity of spectral resources for wireless communication through intelligent sensing and quick resource allocation techniques. Secondary users (SU’s) actively obtain the spectrum access opportunity by supporting primary users (PU’s) in cognitive radio networks (CRNs). In present generation, spectrum access is endowed through cooperative communication-based link-level frame-based cooperative (LLC) principle. In this SUs independently act as conveyors for PUs to achieve spectrum access opportunities. Unfortunately, this LLC approach cannot fully exploit spectrum access opportunities to enhance the throughput of CRNs and fails to motivate PUs to join the spectrum sharing processes. Therefore, to overcome this con, network level cooperative (NLC) principle was used, where SUs are integrated mutually to collaborate with PUs session by session, instead of frame based cooperation for spectrum access opportunities. NLC approach has justified the challenges facing in LLC approach. In this paper we make a survey of some models that have been proposed to tackle the problem of LLC. We show the relevant aspects of each model, in order to characterize the parameters that we should take in account to achieve a spectrum access opportunity.
In this paper, the author provides insights and lessons that can be learned from colleagues at American universities about their online education experiences. The literature review and previous studies of online educations gains are explored and summarized in this research. Emerging trends in online education are discussed in detail, and strategies to implement these trends are explained. The author provides several tools and strategies that enable universities to ensure the quality of online education. At the end of this research paper, the researcher provides examples from Arab universities who have successfully implemented online education and expanded their impact on the society. This research provides a strategy and a model that can be used by universities in the Middle East as a roadmap to implement online education in their regions.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
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
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/
2. IJEECS ISSN: 2502-4752
CMIEP for Voltage Security with the Presence of DGPV (S.A. Syed Mustaffa)
722
RVSI, the weak area was identified for DG or SVC allocation. The author concluded that DG
has more impact on loss reduction and voltage stability improvement compared to SVC.
Recently, metaheuristics optimization techniques are being successfully applied to
optimization problems in power systems [9]. Among those techniques, evolutionary
programming (EP) is considerable a popular technique because of its simplicity, easy
implementation and reliable convergence. EP has the fast converging pattern and good global
searching at the beginning of the simulation. However, EP faces the local minima problem at the
end of the program [10]. In order the overcome the local optima and obtain better convergence,
chaos is introduced. Chaos is a characteristic that describes the complex behavior of a
nonlinear deterministic system [11]. Based on these features, much of chaos as a science is
connected with the notion of ‘sensitive dependence on initial conditions’ [12].
Chaos theory has been adopted successfully in many engineering applications such as
in mechanical and electrical engineering [13]. Moreover, chaos theory and the generation of
chaotic sequences is widely used to replace the random sequences which has led to very
interesting results in many applications, such as optimization of power flow problems [14],
control systems [15], neural networks [16], robotics [17] and others. Optimization algorithms
based on the chaos theory are stochastic search methodologies that have its own advantages
over the existing evolutionary computation and swarm intelligence methods. Due to the non-
repetition of chaos, it can carry out overall searches at higher speeds than stochastic ergodic
searches that depend on probabilities. In this case, the utilization of chaotic optimization
approaches can more easily escape from local minima than can other stochastic optimization
and direct search algorithms, such as multi-directional search, simulated annealing, pure
adaptive search, evolutionary algorithms, swarm intelligence, and others [18–20]. A chaotic
sequence based on a chaotic map that acted as a randomizer was integrated with PSO to
replace the traditional uniform random function for solving the economic dispatch problem[21-
22]. The proposed combined method outperforms other modern metaheuristic optimization
techniques the two constrained economic dispatch case study. In [23], Adaptive chaos clonal
evolutionary programming (ACCEP) is employed to deal with the short-term active power
scheduling of a stand-alone system to minimized the CO2 emissions with certain constraints.
The study showed that with the integration of chaos the simulation converged within a
reasonable time. In [24], chaotic particle swarm optimization (CPSO) was developed to detect
the maximum loadability limit in 14 IEEE bus system. Chaos is incorporated to add diversity to
the particles. The proposed CPSO technique is able to overcome the stagnation of the program
near and provides reliable convergence. Additionally, CPSO technique can achieve higher
maximum loadability factors under different voltage limits.
This paper presents Chaotic Mutation Immune Evolutionary Programming (CMIEP) for
voltage security with the presence of DGPV. In this paper, CMIEP has been applied for optimal
allocation of DGPV for enhancement of voltage stability in the power system. A comparison of
techniques is presented between CMIEP, Chaotic Evolutionary Programming (CEP) and
Evolutionary Programming (EP) with minimization of Fast Voltage Stability Index (FVSI). Results
obtained from the study revealed that CIMEP outperformed EP and CEP in most of the cases in
term of FVSI reduction and overall power system losses.
2. Notation
The notation used throughout the paper is stated:
Indexes:
Z line impedance
jQ receiving bus
iV voltage at the sending bus
nr number of transmission line
k number of DGPV
DGiP generated power from DGPV
GenerationP generated power from the power station
N number of bus in the system
LP total active power load
LossP total active power loss
3. ISSN: 2502-4752
IJEECS Vol. 6, No. 3, June 2017 : 721 – 729
723
minDGP lower limit of DGPV size
maxDGP upper limit of DGPV size
iP size of a DPV
minv lower limit of voltage limit
maxv upper limit of voltage limit
iv voltage magnitude at bus i
nx initial state
p control parameter
3. Research Method
3.1. Minimization of FVSI
FVSI has been widely used as a tool for voltage stability assessor. FVSI is developed
based onthe 2-bus power system, considering power flow via a transmission line [25]. The value
of FVSI range from 0 to 1. The increment in the value of FVSI indicates that the poor
performance of voltage stability in the system. The system is unstable and may face voltage
collapsed when the FVSI value is greater than 0.95. The mathematical equation of FVSI is
written as:
XV
QZ
FVSI
i
j
ij
2
24
(1)
Hence, the objective function, f is to minimize the FVSI and control the voltage level
within the acceptable limit.
iFVSIMinf for nri (2)
This study only consider the FVSI variation when the DGPV is installed in static mode. The
dynamic nature such as the variation of solar irradiance and time domain analysis is not
considered for this study.
3.2. Constraints
The transmission network contains generator buses known as PV bus (power station),
load buses known as PQ bus, (customers) and swing bus. Each PQ bus in the power system is
connected to PV bus. The power is supplied to various areas via the transmission lines. The
most common location of grid connected DGPV are at the load buses due to a shorter distance
for power transfer to the customer and can contribute to minimal power losses. Several
constraints should be taken into account while trying to optimize both location and size of the
DGPV. The constraints are as follows:
3.2.1. Active Power Balance
Referring to principle equilibrium, the power losses and load should be equal to the
power generated from the DGPV unit and the power station.
ki Ni LossLGenerationDGi PPPP (3)
3.2.2. Size of DGPV
The solar irradiance data for 24 hours has been modeled in PSS
®
E by Adrian W. H. Sie
et al in [26]. From the model, the result showed that the DGPV output varies based on the solar
irradiance. Therefore, the inequality constraint for the sizing is given as below.
PPP i maxmin
ki (4)
4. IJEECS ISSN: 2502-4752
CMIEP for Voltage Security with the Presence of DGPV (S.A. Syed Mustaffa)
724
3.2.3. Bus Voltage
The bus voltage magnitudes are bounded between two acceptable operation limit. In
this research, the power factor of the DGPV is assumed as unity power factor. The inequality
constraint on voltage of each bus is expressed as shown in Equation (5).
vvv i maxmin
Ni (5)
3.3. Power System with the Presence of DGPV
Recently, the integration of renewable energy (RE) into the grid system has escalated
dramatically around the world. Among these alternative sources of renewable energy, the solar
photovoltaic (PV) cell has proven to be the best renewable energy source with least negative
impacts on the environment due to its flexibility in term of location and availability compared to
other RE sources [27]. DGPV can be in term of the solar farm is connected to the transmission
line and act as a power generation unit. DGPV has many advantages over centralized power
generation including reduction in power losses, improvement in voltage profile and system
stability, reduction in pollutant emission and relieving transmission and distribution system
congestion [28-29]. However, the performance of DGPV in term of reduction of power losses in
the system dependent upon the solar irradiance penetration level. Therefore, the optimum
location and sizing of DGPV may reduce the power losses and improve the voltage profile within
the allowable limit [30].
3.4. Chaotic Mutation Immune Evolutionary Programming (CMIEP)
In CMIEP algorithm, the concept of optimization is based on evolutionary programming
(EP) and artificial immune system (AIS). Additionally, chaotic sequence was applied as an
alternative to provide diversity in mutation of the approaches. The piecewise linear chaotic
equation is adopted for the mutation.
3.4.1. Evolutionary Programming (EP)
Evolutionary Programming (EP) is a stochastic optimization technique based on the
natural generation and was invented by D. Fogel for prediction of finite state machine [31]. The
process involves random number generation at the initialization, followed by statistical
evaluation, fitness calculation, mutation and finally new generation created as the result of the
selection. Traditionally, in most of the EP algorithm, mutation process was based on the
Gaussian general equation for random modification of the individuals with a small probability.
3.4.2. Chaotic Mutation Based on Piecewise Linear Chaotic Map (PWLCM)
PWLCM has gained increasing attention in chaos research recently due to its simplicity
in representation, efficiency in implementation, as well as good dynamical behavior. It has been
known that PWLCMs are ergodic and have uniform invariant density function on their definition
intervals [32]. The PWLCM with four segments [18], [33] can be denoted in equation (6) as
given below. The PWLCM behaves chaotically in (0,1) whenp is between 0 and 5. In this work,
p=0.4 is heuristically chosen for the mutation process.
( )
{
( )
( )
( )
( )
( )
(6)
Where
[ ]
[ ]
5. ISSN: 2502-4752
IJEECS Vol. 6, No. 3, June 2017 : 721 – 729
725
3.4.3. Flowchart of CMIEP
For a transmission network, load flow analysis is carried out and FVSI value is
computed for each line using Equation (1). For i-j line having the highest value of FVSI, the DG
will be placed at jth bus. The CMIEP algorithm is used for finding the optimum size of DGPV at
optimum location based on a minimum total power loss, with constraints given in equation (3–5).
In this study, the 30 Bus IEEE RTS is used as the test system. The complete flow chart for
DGPV allocation and sizing is represented in Figure 1.
Figure 1. Flowchart of CIMEP algorithm for DGPV allocation and sizing
4. Results and Analysis
The application of the proposed technique (CMIEP) to power system has been
examined in three different cases as single, two and three DGPV installations. The cases were
tested on IEEE 30-Bus radial transmission system (RTS). The reactive power at Bus 30 was
varied at 8, 16, 24 and 32 MVAR for all the cases. The FVSI value without the DGPV unit is
taken as the base case. For each case, the reduction of FVSI optimized using CMIEP is
compared to those optimized using EP and CEP.
Figure 2 shows the results for single DGPV installation optimized using EP, CEP and
CMIEP with a variation of reactive power loading at Bus 30. The results are also compared with
the system without DGPV installation. When Bus 30 was reactively loaded with 8 MVAR, the
highest FVSI reduction, 17.73% is experienced as compared to other loading condition. At 32
MVAR reactive power loading, CMIEP underwent FVSI reduction of 10.60% as compared to EP
and CEP worth 9.30% and 7.53% respectively.Figure 3 shows the results for two DGPV
installations with a variation in reactive power. The CMIEP, EP and CEP showed the highest
FVSI reduction with 23.4%, 21.66% and 21.14% respectively when 8 MVAR was reactively
loaded at Bus 30. CMIEP also shows the best performance at 32 MVAR loading with reduction
of 11.14%. Figure 4 shows the comparison of FVSI reduction for three DGPV installations. The
Read systemdata
Run load flow and calculate
Fitness 1
Perform selection process and
determine the prescribed
candidates for the next
generationClone 10 times for each
individual
Combine parent population and
offspring population. Then sort
the population based on max
FVSI
Run load flow and calculate
Fitness 2
FVSImax ≤ FVSIset
Generate chaotic mutation
parameter and mutate each
individual
Start
End
Assign xk+m as new location
and sk+m as
new DGPV size
Initialize random location
of DGPV, xk
Run pre-DGPV installation load
flow.
Compute FVSI for the system
bus type
is load
bus?
Read bus data
PDGmin ≤ PDG≤ PDGmax
Initialize random sizing
of DGPV, sk
Set optimum PDG at bus kth
Run load flow and calculate
maximum FVSI for the whole
system
Extract the values of bus and
size
Fill in the population pool
Population is full?
Determine x_min and x_max
Meeting
stopping
criterion?
6. IJEECS ISSN: 2502-4752
CMIEP for Voltage Security with the Presence of DGPV (S.A. Syed Mustaffa)
726
same observation can be seen in this figure. The CMIEP has the best performance in most of
the cases.
Figure 2. Comparison of FVSI using different algorithms for single DGPV installation
Figure 3. Comparison of FVSI using different algorithms for 2 DGPV installations
Figure 4. Comparison of FVSI using different algorithms for 3 DGPV installations
7. ISSN: 2502-4752
IJEECS Vol. 6, No. 3, June 2017 : 721 – 729
727
4.4.1. Effect of Number of DG Installation of the Distribution System
Maximum benefits from the DGPV placement can be derived by considering the impact
of the DGPV installation into the power system network. Number of DGPV installations is one of
the important factors to be considered before the installation. This is to significantly analyze the
impact of number of DGPV on FVSI reduction. Table 1 tabulates the results single unit, two
units and three units DGPV installation optimized using CMIEP. It is shown that the losses are
reduced when the number of DGPV installation is increased. This is indicated by the lowest
losses value which is 7.5998 MW experienced by the system when three DGPV installed with
16 MVAR subjected to Bus 30.
Table 1. FVSI reduction and active power losses for multi-DGPV installations using CMIEP
Reactive
Load at
Bus 30
(MVAR)
1 DGPV 2 DGPV 3 DGPV
FVSI
Reduction
(%)
Losses
(MW)
FVSI
Reduction
(%)
Losses
(MW)
FVSI
Reduction
(%)
Losses
(MW)
8 17.73 11.6815 23.39 9.0500 28.26 7.8571
16 3.43 16.2205 4.39 8.6638 6.42 7.5998
24 6.79 15.4902 5.95 9.6162 8.42 8.5259
32 10.59 18.4814 11.15 12.5456 11.34 11.1262
4.4.2 Effect of DGPV on Voltage Condition
The effect of DGPV installation on voltage stability condition can be demonstrated by
the reduction of FVSI values presented in Figure 4 to Figure 6. Based on Table 1, the
percentage of FVSI reduction is achieved at highest reduction which is 17.73% when the
reactive loading condition is 8MVAR. With the optimum location and sizing of DGPV as shown
in Table 2, overall voltage profile is gradually improved. Additionally, CMIEP tabulates the most
consistent solutions. It can be observed Bus 27 is always the best candidate for DGPV
installation regardless the number of DGPV.
Table 2. Optimal location and sizing of DGPV when Bus 30 loaded with 32 MVAR for EP, CEP
and CMIEP
No. of
DGPV
EP CEP CMIEP
Location
(Bus)
Size
(MW)
Location
(Bus)
Size
(MW)
Location
(Bus)
Size
(MW)
1 27 38.9681 25 39.9515 27 58.0515
2
23
30
54.2846
21.4279
17
4
41.2931
42.6142
27
7
52.4677
51.7722
3
7
16
27
55.4604
13.0282
55.2327
28
7
27
54.8685
15.4660
26.4855
27
7
15
59.53632
37.95911
36.13959
5. Conclusion
This paper has presented the chaotic mutation immune evolutionary programming
(CMIEP) for voltage security with the presence of DGPV. In this study, a new approach for
optimum DGPV location and sizing for the minimization of FVSI is developed. CMIEP algorithm
is also proposed to solve the single objective with multi-constraints problem. Results obtained
from the study revealed that the proposed CMIEP techniques outperformed EP and CEP to
achieve significantly high FVSI reduction. The proposed algorithm shows that with three DGPV
units the FVSI can improve up to 28% from its original value. Moreover, the power losses also
significantly improved.
Acknowledgement
The authors would like to acknowledge The Institute of Research Management and
Innovation (IRMI) UiTM, Shah Alam, Selangor, Malaysia and Ministry of Higher Education
(MOHE) for the financial support of this research. This research is supported by MOHE under
8. IJEECS ISSN: 2502-4752
CMIEP for Voltage Security with the Presence of DGPV (S.A. Syed Mustaffa)
728
the Research Acculturation Grant Scheme (RAGS) with project code: 600-RMI/RAGS 5/3
(187/2014).
References
[1] M Mohammadi and M Nafar. Optimal placement of multitypes DG as independent private sector
under pool/hybrid power market using GA-based Tabu Search method. International Journal
Electrical Power Energy System. 2013; 51: 43–53.
[2] T Ananthapadmanabha and S Rani DN. Optimal allocation of combined DG and capacitor units for
voltage stability enhancement. Procedia Technology. 2015; 21: 216–223.
[3] S Gopiya Naik, DK Khatod and MP Sharma. Optimal allocation of combined DG and capacitor for
real power loss minimization in distribution networks. International Journal Electrical Power Energy
System. 2013; 53: 967–973.
[4] MS Male, AA Majd and RR Nezhad. Optimal Determination of Size and Site of DGs in Mesh System
Using PSO. Bulletin Electrical Engineering Informatics. 2014; 3(2): 101–108.
[5] S Sharma and AR Abhyankar. Loss allocation of radial distribution system using Shapley value: A
sequential approach. International Journal Electrical Power Energy System. 2017; 88: 33–41.
[6] J Modarresi, E Gholipour and A Khodabakhshian. A comprehensive review of the voltage stability
indices. Renewable Sustainable Energy Review. 2016; 63: 1–12.
[7] B Poornazaryan, P Karimyan, GB Gharehpetian and M Abedi. Optimal allocation and sizing of DG
units considering voltage stability, losses and load variations. International Journal Electrical Power
Energy System. 2016; 79: 42–52.
[8] A Rath, SR Ghatak and P Goyal. Optimal allocation of distributed generation (DGs) and static VAR
compensator (SVC) in a power system using Revamp Voltage Stability Indicator. in National Power
Systems Conference (NPSC). 2016: 1–6.
[9] K Lenin, BR Reddy and M Suryakalavathi. Reduction of Real Power Loss and Safeguarding of
Voltage Constancy by Artificial Immune System Algorithm. Bulletin Electrical Engineering Informatics.
2015; 4: 88–95.
[10] S Das, R Mallipeddi and D Maity. Adaptive evolutionary programming with p-best mutation strategy.
Swarm Evolutionary Computation. 2013; 9: 58–68.
[11] SH Strogatz. Nonlinear Dynamics and Chaos. Massachusetts: Perseus Books Group. 1994.
[12] L dos S Coelho and VC Mariani. Use of chaotic sequences in a biologically inspired algorithm
[13] S Boccaletti, C Grebogi, Y Lai, H Mancini and D Maza. The control of chaos : theory and applications.
Physics Report. 2000; 329: 103–197.
[14] P Acharjee and SK Goswami. Chaotic particle swarm optimization based robust load flow.
International Journal Electrical Power Energy System. 2010; 32(2): 141–146.
[15] Z Shen and J Li. Chaos control for a unified chaotic system using output feedback controllers.
Mathematics Computational Simulation. 2017; 132: 208–219.
[16] G Xu, F Liu, C Xiu, L Sun and C Liu. Optimization of hysteretic chaotic neural network based on fuzzy
sliding mode control. Neurocomputing. 2016; 189: 72–79.
[17] J Fan, Y Zhang, H Jin, X Wang, D Bie, J Zhao and Y Zhu. Chaotic CPG Based Locomotion Control
for Modular Self-reconfigurable Robot. Journal Bionic Engineering. 2016; 13(1): 30–38.
[18] PT Kapitaniak. Chaos for Engineers: Theory, Applications, and Control, Second. Springer-Verlag
Berlin Heidelberg. 2000.
[19] C Bo, Z Guo, Z Bai and B Cao. Parallel chaos immune evolutionary programming. 2006; 4304.
[20] B Liu, L Wang, YHYH Jin, DXX Huang, LWB Liu and F Tang. Improved particle swarm optimization
combined with chaos. Chaos, Solitons & Fractals. 2005; 25(5): 1261–1271.
[21] LDS Coelho and CS Lee. Solving economic load dispatch problems in power systems using chaotic
and Gaussian particle swarm optimization approaches. International Journal Electrical Power Energy
System. 2008; 30(5): 297–307.
[22] LDS Coelho and VC Mariani. A novel chaotic particle swarm optimization approach using Henon map
and implicit filtering local search for economic load dispatch. Chaos, Solitons and Fractals. 2009;
39(2): 510–518.
[23] YY Hong and JK Lin. Interactive multi-objective active power scheduling considering uncertain
renewable energies using adaptive chaos clonal evolutionary programming. Energy. 2013; 53: 212–
220.
[24] P Acharjee, S Mallick, SS Thakur and SP Ghoshal. Detection of maximum loadability limits and weak
buses using Chaotic PSO considering security constraints. Chaos, Solitons and Fractals. 2011;
44(8): 600–612.
[25] I Musirin and TKA Rahman. On-line voltage stability based contingency ranking using fast voltage
stability index (FVSI). IEEEPES Transmission Distribution Conference Exhibhition. 2002; 2.
[26] AWH Sie, IZ Abidin and H Hashim. A methodology to determine suitable placement of solar
photovoltaic sources in the transmission system taking into account Voltage Stability Index (VSI).
IEEE International Conference Power Energy, PECon 2014. 2014: 226–230.
9. ISSN: 2502-4752
IJEECS Vol. 6, No. 3, June 2017 : 721 – 729
729
[27] SK Sahoo. Renewable and sustainable energy reviews solar photovoltaic energy progress in India: A
review. Renewable Sustainable Energy Review. 2016; 59: 927–939.
[28] M Jamil and AS Anees. Optimal sizing and location of SPV (solar photovoltaic) based MLDG
(multiple location distributed generator) in distribution system for loss reduction, voltage profile
improvement with economical benefits. Energy. 2016; 103: 231–239.
[29] WL Theo, JS Lim, WS Ho, H Hashim and CT Lee. Review of distributed generation (DG) system
planning and optimisation techniques: Comparison of numerical and mathematical modelling
methods. Renewable Sustainable Energy Review. 2017; 67: 531–573.
[30] U Sultana, AB Khairuddin, MM Aman, AS Mokhtar and N Zareen. A review of optimum DG
placement based on minimization of power losses and voltage stability enhancement of distribution
system. Renewable Sustainable Energy Review. 2016; 63: 363–378.
[31] DB Fogel and LJ Fogel. Preliminary Experiments on Discriminating between Chaotic Signals and
Noise Using Evolutionary Programming. Genetic Programming 1996. 1996; (1): 512–520.
[32] T Xiang, X Liao and K Wong. An improved particle swarm optimization algorithm combined with
piecewise linear chaotic map. Applied Mathematic Computation. 2007; 193(1): 231–239.
[33] YF Wang, M De Xie and AM Ji. Research on a piecewise linear chaotic map and its cryptographical
application. Fourth Internationl Conference Fuzzy System Knowledge Discovery FSKD 2007. 2007;
4: 260–263.