International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
This presentation begins with a discussion of the generator as a source feeding a very large remote system (the "single-machine infinite-bus" representation).
Random events & other changes such as random variation in loads continually excite low frequency electromechanical oscillations within the power system which are continually observable in the power system measurements such as those obtained from PMUs. These oscillations also happen to characterize the Small Signal or Oscillatory Stability which is a measure of the power system’s ability to maintain synchronism under small disturbances, and is usually associated with power system’s inability to dampen such oscillations. Damping of these oscillations (typically expressed in %) is therefore a measure of the grid’s robustness to withstand small events or gradual changes in the system. For example, 10% damping implies that the oscillations will decay out in 10 oscillatory cycles while 20 % damping implies that these oscillations will die out in 5 oscillatory cycles (thus higher damping suggests greater robustness and a better ability to mitigate oscillations).
This presentation begins with a discussion of the generator as a source feeding a very large remote system (the "single-machine infinite-bus" representation).
Random events & other changes such as random variation in loads continually excite low frequency electromechanical oscillations within the power system which are continually observable in the power system measurements such as those obtained from PMUs. These oscillations also happen to characterize the Small Signal or Oscillatory Stability which is a measure of the power system’s ability to maintain synchronism under small disturbances, and is usually associated with power system’s inability to dampen such oscillations. Damping of these oscillations (typically expressed in %) is therefore a measure of the grid’s robustness to withstand small events or gradual changes in the system. For example, 10% damping implies that the oscillations will decay out in 10 oscillatory cycles while 20 % damping implies that these oscillations will die out in 5 oscillatory cycles (thus higher damping suggests greater robustness and a better ability to mitigate oscillations).
INTRODUCTION TO POWER SYSTEM STABILITY BY Kundur Power Systems SolutionsPower System Operation
Power System Stability denotes the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with all system variables bounded so that the system integrity is preserved
Integrity of the system is preserved when practically the entire power system remains intact with no tripping of generators or loads, except for those disconnected by isolation of the faulted elements or intentionally tripped to preserve the continuity of operation of the rest of the system
Stability is a condition of equilibrium between opposing forces:
instability results when a disturbance leads to a sustained imbalance between the opposing forces
instability is a run-away or run-down situation
Transient Stability Assessment and Enhancement in Power SystemIJMER
Power system is subjected to sudden changes in load levels. Stability is an important concept
which determines the stable operation of power system. For the improvement of transient stability the
general methods adopted are fast acting exciters, circuit breakers and reduction in system transfer
reactance. The modern trend is to employ FACTS devices in the existing system for effective utilization
of existing transmission resources. The critical clearing time is a measure to assess transient instability.
Using PSAT, the critical clearing time (CCT) corresponding to various faults are calculated. The most
critical faults were identified using this calculation. The CCT for the critical faults were found to change
with change in operating point. The CCT values are predicted using Artificial Neural Network (ANN) to
study the training effects of ANN. TCSC is selected as the FACTS device for transient stability
enhancement. Particle Swarm Optimization method is used to find the optimal position of TCSC using
the objective function real power loss minimization. The result shows that the technique effectively
increases the transient stability of the system
Voltage Stability analysis by using SVC With Fuzzy Logic Controller in Multi ...paperpublications3
Abstract: Power system can be simulated and analyzed based on a mathematical model however; uncertainty still exists due to change of loads and an occurrence of fault. Recently, fuzzy theory highly flexible easily operated and revised, theory is a better choice, especially for a complicated system with many variables. Hence, this work aims to develop a controller based on fuzzy logic to simulate an automatic voltage regulator in transient stability power system analysis. By adding power system stabilizer for tuning of fuzzy logic stabilizing controller there is no need for exact knowledge of power system mathematical model. The fuzzy controller parameters settings are independent due to nonlinear changes in generator and transmission lines operating conditions. Because of that proposed fuzzy controlled power system stabilizer should perform better than the conventional controller. To overcome the drawbacks of conventional power system stabilizer (CPSS), numerous techniques have been proposed in the article. The conventional PSS's effect on the system damping is then compared with a fuzzy logic based PSS while applied to a single machine infinite bus power system.
Voltage collapse mitigation by reactive power compensation at the load sideeSAT Journals
Abstract Power system stability may be defined as the property of a power system that enables it to remain in a state of operating equilibrium under normal operating conditions and to regain an acceptable state of equilibrium after being subjected to a disturbance. A general and formal definition is given below. The IEEE/CIGRE Joint Task Force has proposed the following definition-“Power system stability is the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with most system variables bounded, so that practically the entire system remains intact.” The challenge faced in the modern power system is the collapse of voltages at heavy loads at the load buses of a power system. The voltage collapse will in turn will effect the stability of the power system. In this paper a novel way of mitigating the voltage collapse by supplying the reactive power at load buses is discussed and encouraging simulation results are obtained. The method employed is as fallows. Simulation is done without SVC and STATCOM at load buses. On comparison of the results at the load buses it is seen that with SVC and STATCOM at the load buses voltage collapse is mitigated in spite of heavily loading the system. Keywords: Voltage Collapse, Reactive Power Management, Load Bus, Power System Stability.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IRJET-Review on Power Quality Enhancement in weak Power Grids by Integration ...IRJET Journal
Prathmesh Mayekar, Mahesh Wagh, Nilkanth Shinde "Review on Power Quality Enhancement in weak Power Grids by Integration of Renewable Energy Technologies", International Research Journal of Engineering and Technology (IRJET), Volume2,issue-01 April 2015.e-ISSN:2395-0056, p-ISSN:2395-0072. www.irjet.net
Abstract
During Last decade power quality problems has become more complex at all level of power system. With the increased use of sophisticated electronics, high efficiency variable speed drive, power electronic controllers and also more & more non-linear loads, Power Quality has become an increasing concern to utilities and customers. The modern sensitive, Non-linear and sophisticated load affects the power quality. This paper deals with the issues of low power quality in weak power grids. Initially the various power quality issues are discussed with their definition or occurrence and then finally the solution to mitigate this power quality issues are discussed. The innovative solutions like integration of renewable energy systems along with energy storage to enhance power quality by interfacing with custom power devices are explained in detail. Nearly all sorts of solution for mitigating power quality issue require some sort of DC source for providing active power, which can be supplied by renewable energy source. Also the various energy storage systems are studied.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Steady state stability analysis and enhancement of three machine nine bus pow...eSAT Journals
Abstract
Power System stability study is the important parameter of economic, reliable and secure system planning and operation. Studies
are important during the planning and conceptual design stages of the project as well as during the operating life of the plant
periodically. This paper presents the power system steady state stability analysis for IEEE- 9 bus test system and examines
influence of TCPS FACTS device based controller on test system. It is assumed that system under study has been perturbed from a
steady state equilibrium that prevailed prior to the application of the disturbance. If system is stable, we would expect that for
temporary or permanent disturbance, system will acquire initial or new operating state after a transient period. The stability
study is accessed using Lyapunov’s first method. The effectiveness of damping controller in enhancing the steady state stability is
investigated by incorporating available constraints. For analysis MATLAB software is employed. The conclusions have been
drawn here, based on theoretical and mathematical analysis so as to provide an insight and better understanding of steady state
stability of considered multi machine power system.
Key Words: Lyapunov’s first method, Steady-state stability, Phase portrait, FACTS device, supplementary modulation
controller, eigen value, synchronizing power coefficient, IEEE-9 Bus Test System, Load Flow Study, Differential
algebraic equation.
Efficacy of Facts in Power Oscillation Damping and Renewable IntegrationIOSRJEEE
This paper discusses about the approach towards effective power oscillation damping, root causes for the genesis of power oscillation and various methodologies adopted to eradicate it.This paper presents an unified approach of FACTS controller installation in order to ensure effective power oscillation damping. The power oscillations, if not controlled within time, may aggravate the entire power system’s functioning and ultimate outcome as blackout. The network congestion has been a matter of serious concern to utility operations due to classical transmission corridors and inadequate controllers’ deployment. The necessity of system regulations demands an adequate controller for matching the power requirement variability and this has been demonstrated with STATCOM control feature. This controller enhances the Available Transfer Capability along with security and reliability. IEEE 14 Bus system is simulated and studied with various scenarios with the help of MATLAB and PSAT to identify various complexities and to resolve these issues so as to enhance the ATC, reliability and security
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Transient stability analysis on a multi machine system in psateSAT Journals
Abstract
Modern power system are subject to large disturbances such as three phase short circuit faults. When a fault occurs on a system
the generators rotor angle becomes unstable and thus it losses synchronism with the system and it becomes unstable. Thus
transient stability analysis can be performed on a system in order to understand the generators performance when subjected to a
short circuit fault. When the system is subjected to a fault the generator experiences transient oscillations in rotor speed and
angle which can be effectively suppressed with the incorporation of Automatic Voltage Regulator (AVR) and Power System
Stabilizer (PSS). The simulations have been performed using the MATLAB/PSAT software.
Keywords—Transient stability, Three phase fault Faults, AVR, PSS.
Transient stability analysis and enhancement of ieee 9 bus system ecij
System stability study is the important parameter of economic, reliable and secure power system planning and operation. Power system studies are important during the planning and conceptual design stages of the project as well as during the operating life of the plant periodically. This paper presents the power system stability analysis for IEEE- 9 bus test system. The fault is created on different busses and transient stability is analyzedfor different load and generation conditions. The critical clearing time (CCT) is calculated by
using time domain classical extended equal area criterion method. The system frequency and voltage variation is observed for different fault locations and CCT. The IEEE-9 bus test system is simulated and stability is analyzed on ETAP software
This presentation is about power system voltage stability.
What is voltage stability?
How voltage instability occurs?
How to improve voltage stability of the system?
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
INTRODUCTION TO POWER SYSTEM STABILITY BY Kundur Power Systems SolutionsPower System Operation
Power System Stability denotes the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with all system variables bounded so that the system integrity is preserved
Integrity of the system is preserved when practically the entire power system remains intact with no tripping of generators or loads, except for those disconnected by isolation of the faulted elements or intentionally tripped to preserve the continuity of operation of the rest of the system
Stability is a condition of equilibrium between opposing forces:
instability results when a disturbance leads to a sustained imbalance between the opposing forces
instability is a run-away or run-down situation
Transient Stability Assessment and Enhancement in Power SystemIJMER
Power system is subjected to sudden changes in load levels. Stability is an important concept
which determines the stable operation of power system. For the improvement of transient stability the
general methods adopted are fast acting exciters, circuit breakers and reduction in system transfer
reactance. The modern trend is to employ FACTS devices in the existing system for effective utilization
of existing transmission resources. The critical clearing time is a measure to assess transient instability.
Using PSAT, the critical clearing time (CCT) corresponding to various faults are calculated. The most
critical faults were identified using this calculation. The CCT for the critical faults were found to change
with change in operating point. The CCT values are predicted using Artificial Neural Network (ANN) to
study the training effects of ANN. TCSC is selected as the FACTS device for transient stability
enhancement. Particle Swarm Optimization method is used to find the optimal position of TCSC using
the objective function real power loss minimization. The result shows that the technique effectively
increases the transient stability of the system
Voltage Stability analysis by using SVC With Fuzzy Logic Controller in Multi ...paperpublications3
Abstract: Power system can be simulated and analyzed based on a mathematical model however; uncertainty still exists due to change of loads and an occurrence of fault. Recently, fuzzy theory highly flexible easily operated and revised, theory is a better choice, especially for a complicated system with many variables. Hence, this work aims to develop a controller based on fuzzy logic to simulate an automatic voltage regulator in transient stability power system analysis. By adding power system stabilizer for tuning of fuzzy logic stabilizing controller there is no need for exact knowledge of power system mathematical model. The fuzzy controller parameters settings are independent due to nonlinear changes in generator and transmission lines operating conditions. Because of that proposed fuzzy controlled power system stabilizer should perform better than the conventional controller. To overcome the drawbacks of conventional power system stabilizer (CPSS), numerous techniques have been proposed in the article. The conventional PSS's effect on the system damping is then compared with a fuzzy logic based PSS while applied to a single machine infinite bus power system.
Voltage collapse mitigation by reactive power compensation at the load sideeSAT Journals
Abstract Power system stability may be defined as the property of a power system that enables it to remain in a state of operating equilibrium under normal operating conditions and to regain an acceptable state of equilibrium after being subjected to a disturbance. A general and formal definition is given below. The IEEE/CIGRE Joint Task Force has proposed the following definition-“Power system stability is the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with most system variables bounded, so that practically the entire system remains intact.” The challenge faced in the modern power system is the collapse of voltages at heavy loads at the load buses of a power system. The voltage collapse will in turn will effect the stability of the power system. In this paper a novel way of mitigating the voltage collapse by supplying the reactive power at load buses is discussed and encouraging simulation results are obtained. The method employed is as fallows. Simulation is done without SVC and STATCOM at load buses. On comparison of the results at the load buses it is seen that with SVC and STATCOM at the load buses voltage collapse is mitigated in spite of heavily loading the system. Keywords: Voltage Collapse, Reactive Power Management, Load Bus, Power System Stability.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IRJET-Review on Power Quality Enhancement in weak Power Grids by Integration ...IRJET Journal
Prathmesh Mayekar, Mahesh Wagh, Nilkanth Shinde "Review on Power Quality Enhancement in weak Power Grids by Integration of Renewable Energy Technologies", International Research Journal of Engineering and Technology (IRJET), Volume2,issue-01 April 2015.e-ISSN:2395-0056, p-ISSN:2395-0072. www.irjet.net
Abstract
During Last decade power quality problems has become more complex at all level of power system. With the increased use of sophisticated electronics, high efficiency variable speed drive, power electronic controllers and also more & more non-linear loads, Power Quality has become an increasing concern to utilities and customers. The modern sensitive, Non-linear and sophisticated load affects the power quality. This paper deals with the issues of low power quality in weak power grids. Initially the various power quality issues are discussed with their definition or occurrence and then finally the solution to mitigate this power quality issues are discussed. The innovative solutions like integration of renewable energy systems along with energy storage to enhance power quality by interfacing with custom power devices are explained in detail. Nearly all sorts of solution for mitigating power quality issue require some sort of DC source for providing active power, which can be supplied by renewable energy source. Also the various energy storage systems are studied.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Steady state stability analysis and enhancement of three machine nine bus pow...eSAT Journals
Abstract
Power System stability study is the important parameter of economic, reliable and secure system planning and operation. Studies
are important during the planning and conceptual design stages of the project as well as during the operating life of the plant
periodically. This paper presents the power system steady state stability analysis for IEEE- 9 bus test system and examines
influence of TCPS FACTS device based controller on test system. It is assumed that system under study has been perturbed from a
steady state equilibrium that prevailed prior to the application of the disturbance. If system is stable, we would expect that for
temporary or permanent disturbance, system will acquire initial or new operating state after a transient period. The stability
study is accessed using Lyapunov’s first method. The effectiveness of damping controller in enhancing the steady state stability is
investigated by incorporating available constraints. For analysis MATLAB software is employed. The conclusions have been
drawn here, based on theoretical and mathematical analysis so as to provide an insight and better understanding of steady state
stability of considered multi machine power system.
Key Words: Lyapunov’s first method, Steady-state stability, Phase portrait, FACTS device, supplementary modulation
controller, eigen value, synchronizing power coefficient, IEEE-9 Bus Test System, Load Flow Study, Differential
algebraic equation.
Efficacy of Facts in Power Oscillation Damping and Renewable IntegrationIOSRJEEE
This paper discusses about the approach towards effective power oscillation damping, root causes for the genesis of power oscillation and various methodologies adopted to eradicate it.This paper presents an unified approach of FACTS controller installation in order to ensure effective power oscillation damping. The power oscillations, if not controlled within time, may aggravate the entire power system’s functioning and ultimate outcome as blackout. The network congestion has been a matter of serious concern to utility operations due to classical transmission corridors and inadequate controllers’ deployment. The necessity of system regulations demands an adequate controller for matching the power requirement variability and this has been demonstrated with STATCOM control feature. This controller enhances the Available Transfer Capability along with security and reliability. IEEE 14 Bus system is simulated and studied with various scenarios with the help of MATLAB and PSAT to identify various complexities and to resolve these issues so as to enhance the ATC, reliability and security
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Transient stability analysis on a multi machine system in psateSAT Journals
Abstract
Modern power system are subject to large disturbances such as three phase short circuit faults. When a fault occurs on a system
the generators rotor angle becomes unstable and thus it losses synchronism with the system and it becomes unstable. Thus
transient stability analysis can be performed on a system in order to understand the generators performance when subjected to a
short circuit fault. When the system is subjected to a fault the generator experiences transient oscillations in rotor speed and
angle which can be effectively suppressed with the incorporation of Automatic Voltage Regulator (AVR) and Power System
Stabilizer (PSS). The simulations have been performed using the MATLAB/PSAT software.
Keywords—Transient stability, Three phase fault Faults, AVR, PSS.
Transient stability analysis and enhancement of ieee 9 bus system ecij
System stability study is the important parameter of economic, reliable and secure power system planning and operation. Power system studies are important during the planning and conceptual design stages of the project as well as during the operating life of the plant periodically. This paper presents the power system stability analysis for IEEE- 9 bus test system. The fault is created on different busses and transient stability is analyzedfor different load and generation conditions. The critical clearing time (CCT) is calculated by
using time domain classical extended equal area criterion method. The system frequency and voltage variation is observed for different fault locations and CCT. The IEEE-9 bus test system is simulated and stability is analyzed on ETAP software
This presentation is about power system voltage stability.
What is voltage stability?
How voltage instability occurs?
How to improve voltage stability of the system?
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Controlling and Reducing of Speed for Vehicles Automatically By Using Rf Tech...IJERA Editor
For vehicle safety and safety for passengers in vehicle is an important parameter. Most of the vehicles get
accident because no proper safety measures are taken especially at curves and hair pin bends humps and any
obstacles in front of the vehicle. This system can be used for the prevention of such a problem by indicating a
pre indication and also reducing the speed of vehicles by reducing the fuel rate of vehicle. As the action is in
terms of fuel rate so the vehicle automatically goes to control and avoids the accidents. At curves and hair pin
bends the line of sight is not possible for the drivers so the special kind of transmitter which is tuned at a
frequency of 433MHZ are mounted as these transmitters continuously radiate a RF signal for some particular
area. As the vehicle come within this radiation the receiver in the vehicle gets activate. The transmitter used here
is a coded transmitter which is encoded with encoder. The encoder provides a 4 bit binary data which is serially
transmitted to transmitter. The transmitter used here is ASK type (amplitude shift keying) which emits the RF
radiation.
Land Use and Land Cover Change Detection in Tiruchirappalli District Using Re...IJERA Editor
Land use and land cover is dominant role in the part of urbanization. As the rapid urbanization led various activities
in a region and these changes generally takes place in the agricultural land and caused decrease of arable land .The
satellite imageries LANDSAT 5TM (1990), LANDSAT 7ETM (2000) AND LISS 111 (2010) data’s are used. The
scales are 1:50,000. 1990, 2000 and 2010 covering a period of 19 years the aerial distribution of the land use and
land cover changes has been observed. The changes were identified ,in which the decrease of Agricultural land,
Natural vegetation , Scrub land and Water body and increase of Built up land, Fallow land, River sand and Without
scrub land. The land use and land cover maps are prepared by using GIS software to evaluate the changes and it is
showed strong variation.
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Location of Shunt FACTS Devices for First-Swing Stability Enhancement in Inte...Editor IJMTER
This paper deals with the location of shunt FACTS devices to improve transient stability
in a long transmission line with predefined direction of real power flow. Shunt Flexible AC
Transmission System (FACTS) devices, when placed at the mid-point of a long transmission line,
play an important role in controlling the reactive power flow to the power network and hence both
the system voltage fluctuations and transient stability. The validity of the mid-point location of shunt
FACTS devices was verified using Simulink, with different shunt FACTS devices, namely static var
compensator (SVC) and static synchronous compensator (STATCOM) in a long transmission line
using the actual line model. It has been observed that the FACTS devices, when placed slightly offcentre towards sending-end, give better performance in improving transient stability and the location
depends on the amount of local/through load. The results are experimented and simulated on
MATLAB/Simulink environment.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
A Review on Power System Voltage Stability and Optimization TechniquesIJERA Editor
Power system voltage stability is a one of the major focused areas in recent days due to mismatch between generation and demand. Maintenance of voltage stability is a challenging issue in planning and security assessment of power systems. Voltage stability is the ability of a power system to maintain steady acceptable voltages at all buses in the power system under normal operating conditions and after being subjected to a disturbance. Long-term voltage instability problems can occur in heavily loaded systems where the electrical distance is large between the generator and the load. Timely application of reactive power compensation or load shedding may prevent this type of voltage instability. System reactive power handling capacity can be improved with Flexible AC Transmission System (FACTS) devices. Identification of critical system locations to undertake appropriate remedial measures in operation is the concern. This paper reviews the performance of various types FACTS controllers in power system voltage stability problem and focuses on different optimization methods implemented for optimal placement and sizing of FACTS devices to minimize power losses.
Facts controllers for power flow control a brief reviewDHEERAJ DHAKAR
This paper provides a review of FACTS devices. The value of these FACTS is the improvement of security and efficiency of power transmission networks. Fast controllability in emergency situation provides increased flexibility and therefore stability and security advantages. The flexibility in control allows operating closer to stability limits and improve the efficiency of existing networks
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Swing, voltage stability and power transfer capability in transmission system...eSAT Journals
Abstract In modern era, the increasing size of the power system, to maximize the use of existing systems and to provide adequate voltage support is an emphasis on finding solutions. This flexibility is needed electricity. Better placed than the Flexible AC Transmission Systems (FACTS) to control the flow of electricity, and to provide voltage support can be effective in turn resulting in less damage. The impact of these tools on line flow and bus voltage profile at random algorithm to determine the optimal number of ratings have been studied by keeping them better . The FACTS devices are expensive cause of that FACTS type, number and location of the FACTS devices is very important, for decide the optimal location and parameters of FACTS devices. FACTS are used in the following purposes: Transmission pricing issues by maximizing social welfare with or without consideration of FACTS’ costs; Better utilization of FACT by maximizing FACTS devices total transferred power; Reactive power or voltage control by minimizing transmission losses, or voltage fluctuation. Increase system’s security under emergency by minimizing transmission lines loadability. Power flow control, a current long transmission line, plays an important role within the energy system. The letter swings, long-distance transmission line voltage and power flow control in unified power flow controller (UPFC) based compensation associated series or shunt FACTS devices are employed. Devices such as the proposed transmission line, between the end of the sending and receiving end to the transmission line is used in places as different. Here also deals with determining the optimum placement of Flexible AC Transmission Systems (FACTS) damping out swings, voltage and improves power transfer devices for a long transmission line. Here the concept of compensation mid-point of facts is presented for optimal placement. Keywords: Stability, first swings, rotor angle, power transfer, Flexible AC Transmission Systems (FACTS), Unified Power Flow Controller (UPFC), reactive power
Investigation and Comparison of the Effect of Facts Devices, Capacitors and L...IJAPEJOURNAL
This paper studies the important power system phenomenon and voltage stability by using continuation power flow method. Voltage collapse scenario is presented which can be a serious result of voltage instability and also the parameters that affected by voltage collapse are discussed. In analyzing power system voltage stability, continuation power flow method is utilized which consists of successive load flows. In this paper steady-state modeling of Static VAR Compensator (SVC) and Unified Power Flow Controller (UPFC) and effect of compensator and variation of line reactance on the voltage stability have been studied and Comparison between performance of UPFC and SVC and installation shunt capacitor and variation of line reactance for improve voltage stability has been done.Case studies are carried on 11 bus network in two areas. Simulation is done with PSAT in MATLAB. Continuation Power Flow was implemented using Newton Raphson method. Simulation results show the proper performance of UPFC, SVC, installation shunt capacitor and variation of line reactance to improve voltage control and significantly increase the loadability margin of power systems.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
Classification Of Power System StabilityAravind Shaji
The Slide Deals With Power System Stability. Contents Include
Power System Stability Overview
Power System Stability: A Proposed Definition
Need of Stability Classification
Classification of stability
Power System Stability Classification
Rotor Angle Stability
Voltage Stability
Frequency Stability
Rotor Angle Stability vs. Voltage Stability
References
Comparison of Shunt Facts Devices for the Improvement of Transient Stability ...IJSRD
This paper presents, the performance of STATCOM placed at midpoint of the two machine power system and compared with the performance of SVC. The comparison of various results found for the different type of faults (single line, double line & three phase fault) occur in long transmission line, and their removal by using shunt FACTS devices is analysed. Computer simulation results under a severe disturbance condition (three phase fault) for different fault clearing times, and different line lengths are analyzed. Both controllers are implemented using MATLAB/SIMULINK. Simulation results shows that the STATCOM with conventional PI controller installed with two machine three bus systems provides better damping oscillation characteristics in rotor angle as compared to two machine power system installed with SVC. The transient stability of two machine system installed with STATCOM has been improved considerably and post settling time of the system after facing disturbance is also improved.
Comparison of Shunt Facts Devices for the Improvement of Transient Stability ...IJSRD
This paper presents, the performance of STATCOM placed at midpoint of the two machine power system and compared with the performance of SVC. The comparison of various results found for the different type of faults (single line, double line & three phase fault) occur in long transmission line, and their removal by using shunt FACTS devices is analysed. Computer simulation results under a severe disturbance condition (three phase fault) for different fault clearing times, and different line lengths are analyzed. Both controllers are implemented using MATLAB/SIMULINK. Simulation results shows that the STATCOM with conventional PI controller installed with two machine three bus systems provides better damping oscillation characteristics in rotor angle as compared to two machine power system installed with SVC. The transient stability of two machine system installed with STATCOM has been improved considerably and post settling time of the system after facing disturbance is also improved.
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USING SSSC & STATCOM --IMPROVE TRANSIENT STABILITY--P & Q OSICALLATIONSIJSRD
In a deregulated power system, the electric power demand is extending ordinary which may lead to overloads and loss of generation. Transient stability studies put a fundamental part in power systems, which give information related to the capacity of a power structure to stay in synchronism during major disturbances resulting from either the loss of generation or transmission facilities, sudden or sustained changes. The examination of transient quality is discriminating to work the power structure more secure and this paper focuses on growing the transient relentlessness using FACTS devices like Static Synchronous Series Compensator (SSSC) and static synchronous compensator (STATCOM). These FACTS contraptions are in a perfect world set on transmission structure using Sensitivity approach framework.
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Connector Corner: Automate dynamic content and events by pushing a button
Et33879883
1. Priyank Srivastava, Rashmi Pardhi / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.879-883
879 | P a g e
A Review on Power System Stability and Applications of FACT
Devices
Priyank Srivastava, Rashmi Pardhi
Department of Electrical Engineering. Bhabha Engineering & Research Institute.(BHOPAL)
Department of Electrical Engineering. Radharaman Engineering college.(BHOPAL)
Abstract
stability is one of the major concerns
related to power system. The instability causes
the fluctuations in different parameters of power
system but the voltage and frequency are most
importantly considered because may cause great
damage and even cause complete shutdown of
power system. This paper presents brief overview
of different types of instabilities in power system
and the techniques used to overcome it. The
paper also compares the applicability of different
techniques on the basis of performance.
Keywords: power system stability, FACT devices.
1. Introduction
The stability of the power system is defined
as “the ability of an electric power system, for a
given initial operating condition, to regain a state of
operating equilibrium after being subjected to a
physical disturbance, with most system variables
bounded so that practically the entire system
remains intact” [1]. According to above definition it
is clear that if system fails to get operating
equilibrium then it will be called instable. There are
many kind of instabilities exists in the modern
power systems (such as voltage, frequency etc.) and
accordingly the different stabilization methods are
used. The stabilization processes basically works by
compensation of the causing the instability in past
this is done by connecting and disconnecting the
capacitor, inductors or combination of both after
that synchronous condenser, saturated reactor,
thyristor controlled reactor, fixed capacitor thyristor
controlled reactor, thyristor switched capacitor were
used; but in present days this is performed by more
advanced devices like STATCOM, VSC, TCSC etc.
these devices evolves the intelligent controlling and
fast switching power devices like MOSFET and
IGBT the capability of fast switching makes them
feasible for providing precise and smooth
controlling. The intelligent controlling is performed
by the complex calculations which are done by
either analog circuits or microprocessors. Although
analog devices performed well but in recent past
developments in the semiconductor technology
makes the digital controllers as first choice because
of their capabilities and lower cost.
2. Types of Instabilities in Power System
The classification to be introduced here is
based on the physical mechanism being the main
driving force in the development of the associated
instability.
Power System Stability (PSS) problems may be
classified as [2]:
• Angle Stability
• Voltage Stability
• Frequency (Mid- and Long-Term) Stability
Each category can be divided to [2]:
Small-Signal (Dynamic) Stability: Determines if
system remains in synchronism following a
small disturbance (e.g., small load and/or
generation variations).
Transient Stability: Determines if system
remains in synchronism following a major
disturbance (e.g., transmission fault, sudden load
change, loss of generation, line switching). The
transient stability can further be divided into two
classes.
First-Swing Stability: for 1st second after a
system fault (simple generator model & no control
model).
Multi Swing Stability: system analysis over long
period of time (more sophisticated machine
model).
Figure 1: Classification of power system stability
[3].
2.1 Rotor Angular or Synchronous Stability
The rotor angle stability problem involves
the study of the electromechanical oscillations
inherent in power systems. A fundamental factor in
this problem is the manner in which the power
outputs of synchronous machines vary as their rotor
angles change. The mechanism by which
interconnected synchronous machines maintain
synchronism with one another is through restoring
forces, which act whenever there are forces tending
2. Priyank Srivastava, Rashmi Pardhi / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.879-883
880 | P a g e
to accelerate or decelerate one or more machines
with respect to other machines. Under steady-state
conditions, there is equilibrium between the input
mechanical torque and the output electrical torque of
each machine, and the speed remains constant. If the
system is perturbed, this equilibrium is upset,
resulting in acceleration or deceleration of the rotors
of the machines according to the laws of motion of a
rotating body. If one generator temporarily runs
faster than another, the angular position of its rotor
relative to that of the slower machine will advance.
The resulting angular difference transfers part of the
load from the slow machine to the fast machine,
depending on the power angle relationship. This
tends to reduce the speed difference and hence the
angular separation. The power angle relationship, as
discussed above, is highly nonlinear. Beyond a
certain limit, an increase in angular separation is
accompanied by a decrease in power transfer; this
increases the angular separation further and leads to
instability. For any given situation, the stability of
the system depends on whether or not the deviations
in angular positions of the rotors result in sufficient
restoring torques. It should be noted that loss of
synchronism can occur between one machine and
the rest of the system, or between groups of
machines, possibly with synchronism maintained
within each group after separating from each other
[3].
2.2 Voltage Stability
When it comes to reactive power balance
the situation is not as clear and simple as concerning
active power. There is always a balance between
“produced” and “consumed” reactive power in
every node of a network. This is in fact a direct
consequence of Kirchoff’s first current law. When
one talks about imbalance in this context we mean
that the injected reactive power is such, normally
too small, that the voltage in the node cannot be kept
to acceptable values. (At low load the injected
reactive power could be high resulting in a too high
voltage, possibly higher than the equipment might
be designed for. This is of course not desirable but
it could usually be controlled in such a way that no
instabilities develop.) When we talk about
imbalance in this case we thus mean that the
injected reactive power differs from the desired
injected reactive power, needed to keep the desired
voltage. If this imbalance gets too high, the voltages
exceed the acceptable range [1].
2.3 Frequency Stability
Frequency stability refers to the ability of a
power system to maintain steady frequency
following a severe system upset resulting in a
significant imbalance between generation and load.
It depends on the ability to maintain/restore
equilibrium between system generation and load,
with minimum unintentional loss of load. Instability
that may result occurs in the form of sustained
frequency swings leading to tripping of generating
units and/or loads. Severe system upsets generally
result in large excursions of frequency, power flows,
voltage, and other system variables, thereby
invoking the actions of processes, controls, and
protections that are not modeled in conventional
transient stability or voltage stability studies. These
processes may be very slow, such as boiler
dynamics, or only triggered for extreme system
conditions, such as volts/Hertz protection tripping
generators. In large interconnected power systems,
this type of situation is most commonly associated
with conditions following splitting of systems into
islands. Stability in this case is a question of
whether or not each island will reach a state of
operating equilibrium with minimal unintentional
loss of load. It is determined by the overall response
of the island as evidenced by its mean frequency,
rather than relative motion of machines. Generally,
frequency stability problems are associated with
inadequacies in equipment responses, poor
coordination of control and protection equipment, or
insufficient generation reserve.
3. Device used for Enhancement of the
Stability of Power System
The conventional control devices like
synchronous condenser, saturated reactor, thyristor
controlled reactor, fixed capacitor thyristor
controlled reactor, thyristor switched capacitor
having less system stability limit, less
enhancement of system damping, less voltage
flicker control when compared to emerging facts
devices like TCSC, STATCOM and UPFC [7].
This Section investigates only FACT devices for
system stability.
3.1. Static VAR Compensator (SVC)
Static VAR systems are applied by utilities
in transmission applications for several purposes.
The primary purpose is usually for rapid control of
voltage at weak points in a network. Installations
may be at the midpoint of transmission
interconnections or at the line ends. Static VAR
Compensators are shunt connected static generators
/ absorbers whose outputs are varied so as to control
voltage of the electric power systems. The SVC is
connected to a coupling transformer that is
connected directly to the ac bus whose voltage is to
be regulated.
Typically, an SVC comprises one or more
banks of fixed or switched shunt capacitors or
reactors, of which at least one bank is switched by
thyristors (figure 1). Elements which may be used to
make an SVC typically include:
Thyristor controlled reactor (TCR), where the
reactor may be air- or iron-cored.
Thyristor switched capacitor (TSC).
Harmonic filter(s).
3. Priyank Srivastava, Rashmi Pardhi / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.879-883
881 | P a g e
Mechanically switched capacitors or reactors
(switched by a circuit breaker).
The firing angle can be controlled through a PI
(Proportional + Integral) controller in such a way
that the voltage of the bus, where the SVC is
connected, is maintained at the reference value.
Figure 1: Typical SVC configuration
3.2 Thyristor Controlled Series Compensator
(TCSC)
TCSC is one of the most important and
best known FACTS devices, which has been in use
for many years to increase line power transfer as
well as to enhance system stability. The main circuit
of a TCSC is shown in Figure. 1. The TCSC
consists of three main components: capacitor bank
C, bypass inductor L and bidirectional thyristors
SCR1 (T1) and SCR2 (T2). The firing angles of the
thyristors are controlled to adjust the TCSC
reactance in accordance with a system control
algorithm, normally in response to some system
parameter variations. According to the variation of
the thyristor firing angle or conduction angle, this
process can be modeled as a fast switch between
corresponding reactance offered to the power
system.
Figure 2: Single machine infinite bus power system
with TCSC
3.3 Static Compensator (STATCOM)
It is a device connected in derivation,
basically composed of a coupling transformer, that
serves of link between the electrical power system
(EPS) and the voltage synchronous controller
(VSC), that generates the voltage wave comparing it
to the one of the electric system to realize the
exchange of reactive power. The control system of
the STATCOM adjusts at each moment the inverse
voltage so that the current injected in the network is
in quadrature to the network voltage, in these
conditions P=0 and Q=0.
In its most general way, the STATCOM can be
modeled as a regulated voltage source Vi connected
to a voltage bar Vs through a transformer.
The STATCOM uses a VSC interfaced in shunt to a
transmission line. In most cases the DC voltage
support for the VSC will be provided by the
DC capacitor of relatively small energy storage
capability hence, in steady state operation, active
power exchanged with the line has to be maintained
at zero, as shown symbolically in the Figure 3.
Figure 3: STATCOM Connections.
With the active power constraint
imposed, the control of the STATCOM is
reduced to one degree of freedom, which is
used to control the amount of reactive power
exchanged with the line. Accordingly, a STATCOM
is operated as a functional equivalent of a static
VAR compensator; it provides faster control than
an SVC and improved control range.
3.4 Static Synchronous Series Compensator
(SSSC)
This device work the same way as the
STATCOM. It has a voltage source converter
serially connected to a transmission line through a
transformer. It is necessary an energy source to
provide a continuous voltage through a condenser
and to compensate the losses of the VSC. A SSSC
is able to exchange active and reactive power
with the transmission system. But if our only
aim is to balance the reactive power , the
energy source could be quite small. The injected
voltage can be controlled in phase and magnitude if
we have an energy source that is big enough for the
purpose. With reactive power compensation only the
voltage is controllable, because the voltage
vector forms 90º degrees with the line intensity.
In this case the serial injected voltage can delay
or advanced the line current. This means that the
SSSC can be uniformly controlled in any value, in
the VSC working slot.
The Static Synchronous Series Compensator (SSSC)
uses a VSC interfaced in series to a transmission
line, as shown in the Figure 4.
4. Priyank Srivastava, Rashmi Pardhi / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.879-883
882 | P a g e
Figure 3: SSSC Connections.
Again, the active power exchanged with the line has
to be maintained at zero hence, in steady state
operation, SSSC is a functional equivalent of an
infinitely variable series connected capacitor. The
SSSC offers fast control and it is inherently neutral
to sub-synchronous resonance.
3.5 Unified Power Flow Controller (UPFC)
A unified power flow controller (UPFC) is
the most promising device in the FACTS concept.
The UPFC can provide simultaneous control of all
basic power system parameters (transmission
voltage, impedance and phase angle). The controller
can fulfill functions of reactive shunt compensation,
series compensation and phase shifting meeting
multiple control objectives. From a functional
perspective, the objectives are met by applying a
boosting transformer injected voltage and an
exciting transformer reactive current. The injected
voltage is inserted by a series transformer. Besides
transformers, the general structure of UPFC contains
also a” back to back” AC to DC voltage source
converters operated from a common DC link
capacitor, Figure 1. First converter (CONV1) is
connected in shunt and the second one (CONV2) in
series with the line. The shunt converter is primarily
used to provide active power demand of the series
converter through a common DC link. Converter 1
can also generate or absorb reactive power, if it is
desired, and thereby provide independent shunt
reactive compensation for the line. Converter 2
provides the main function of the UPFC by injecting
a voltage with controllable magnitude and phase
angle in series with the line via a voltage source
(Figure 5)
Figure 5: Implementation of the UPFC by back-to-
back voltage source converters
4. Comparison of performance of different
fact devices for specific conditions
Conditions Vs FACT Devices
Comparison
SVC
TCSC
STATCO
M
SSSC
UPFC
Reactive Power Generation/Absorption G A E E E
Voltage control G A E A E
Voltage stability improvement G G E E E
Power flow control A A G E E
Rotor angle stability improvement A G A E E
Flicker mitigation G D E D E
Harmonics reduction D D G G E
Frequency stability improvement A A G A G
Where A = Average, G = Good, E = Excellent and
D = Depends upon Conditions.
5. Conclusion
The paper discussed the various types of
instability issues involved in power system it also
discussed the FACT devices, their working,
Structure and placement in power system. Finally a
comparison tablet is presented for comparison of the
performance of FACT devices for different system
conditions. The comparison results shows that the
UPFC shows the best performance followed by the
STATCOM while SSSC comes at the third position
and the devices TCSC and VAR gets the last
position in the table this is because of lower
controllability of the thyristors. Finally it can be said
that the paper provides a non mathematical
explanation and a fair comparison of different
FACT devices.
References
[1] Dr. Mohammad A.S. Masoum
“Synchronous Machine Dynamics”,
Electrical & Computer Engineering
Department Curtin University of
Technology Perth, West Australia
[2] M.P.Donsión, J.A. Güemes and J.M.
Rodríguez” Power Quality. Benefits of
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[3] Richard G. Farmer “Power System
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Farmer, Arizona State University
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“Comparison of FACTS Devices for Power
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5. Priyank Srivastava, Rashmi Pardhi / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.879-883
883 | P a g e
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