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.
Efficacy of Facts in Power Oscillation Damping and Renewable IntegrationIOSRJEEE
This document summarizes research on using flexible AC transmission system (FACTS) devices to improve power oscillation damping and facilitate renewable energy integration. It discusses how power oscillations can lead to instability if not controlled and how FACTS devices like STATCOM and SVC can enhance stability. It presents simulations of the IEEE 14-bus system that demonstrate improved damping from these controllers. Eigenvalue analysis shows STATCOM shifts modes further into the stable region than SVC. Both STATCOM and SVC integration helps renewable sources by mitigating power quality issues to allow more distributed generation on the grid.
Transient stability in power system is vital to be addressed due to large disturbances that could damage the system such as load changes and voltage increases. This paper presents a multi-machine transient stability using the Static Synchronous Series Compensator (SSSC). SSSC is a device that is connected in series with the power transmission line and produces controllable voltage which contribute to a better performance in the power system stability. As a result, this research has observed a comparison of the synchronization of a three-phase system during single-phase faults before and after installing the SSSC device. In addition, this research investigates the ability of three different types of controllers i.e. Proportional Integral (PI), Proportional Integral Derivation (PID), and Generic controllers to be added to the SSSC improve the transient stability as it cannot operate by itself. This is because the improvement is too small and not able to achieve the desired output. The task presented is to improve the synchronization of the system and time taken for the voltage to stabilize due to the fault. The simulation result shows that the SSSC with an additional controller can improve the stability of a multi-machine power system in a single phase fault.
Comparison of facts devices for two area power system stability enhancement u...IAEME Publication
This document summarizes a research paper that compares the performance of SVC and STATCOM FACTS devices for enhancing transient stability in a two area power system modelled in MATLAB. The paper reviews previous research on using FACTS controllers like SVC, STATCOM, SSSC, TCSC and UPFC to improve power system stability. Simulation results from the paper indicate that a two machine system installed with STATCOM provided better damping of rotor angle oscillations compared to an SVC installation, demonstrating improved transient stability when using a STATCOM.
This paper presents a method to improve transient stability and damping of low frequency oscillations in a multi-machine power system using adaptive neuro-fuzzy control of FACTS devices. A Simulink model of a three generator power system equipped with a UPFC is developed. Simulation results show that a UPFC controlled using an adaptive neuro-fuzzy inference system controller more effectively improves transient stability and damps power oscillations compared to using SSSC. The neuro-fuzzy controller is trained using a hybrid learning algorithm to tune its parameters online based on generator speed deviation and acceleration as inputs.
Static Synchronous Series Compensator (SSSC) with Superconducting Magnetic En...IDES Editor
Static Synchronous Series Compensator (SSSC) has
been designed with Superconducting Magnetic Energy Storage
(SMES) system. A closed loop control scheme has been
proposed with PI controller and real and reactive powers are
taken as references. A 48 pulse voltage source inverter is
designed for the SSSC. Control scheme for the chopper circuit
of SMES coil is also designed. A three area system is taken as
the test system and the operation of SSSC with SMES is
analysed for various transient disturbances. Test results under
different disturbances and operating conditions show the
proposed SSSC with SMES is effective in damping out the
power system oscillations.
This document discusses constraints and load flow analysis in power systems. It outlines four key constraints: active power constraint, reactive power constraint, voltage magnitude constraint, and load angle constraint. It also describes load flow analysis as a balanced mechanism between demand and generation under incremental loading. Load flow analysis is important for the safe and future operation of power systems. The document further discusses bus classification, basic power flow conditions including the proportional relationships between reactive power and voltage and active power and load angle. It also covers the development of the Y-bus matrix considering line resistances and inductances alone and then including line capacitances.
Power Flow Control in Power System Using FACT Device Thyristor Controlled Ser...IOSR Journals
This document summarizes a study on using Flexible AC Transmission System (FACTS) devices for power flow control in a power system. Specifically, it models and simulates the use of Thyristor Controlled Series Capacitor (TCSC) and Static VAR Compensator (SVC) in a two-area, four-machine 11-bus test system using MATLAB/Simulink. TCSC is installed between buses 9 and 10 to reduce line reactance and improve power flow. SVC is installed at bus 9 for voltage control. Simulation results show that TCSC and SVC effectively control active and reactive power flows and bus voltages in the system.
There are two broad classes of power system stability:
1) Steady state stability - The ability of a system to maintain equilibrium after a small disturbance.
2) Transient stability - The ability to maintain synchronism during large disturbances like faults.
Factors influencing transient stability include generator loading, fault conditions, clearing time, reactances, and inertia. Methods to improve it include high-speed excitation, series capacitors, fault clearing and independent pole operation.
Efficacy of Facts in Power Oscillation Damping and Renewable IntegrationIOSRJEEE
This document summarizes research on using flexible AC transmission system (FACTS) devices to improve power oscillation damping and facilitate renewable energy integration. It discusses how power oscillations can lead to instability if not controlled and how FACTS devices like STATCOM and SVC can enhance stability. It presents simulations of the IEEE 14-bus system that demonstrate improved damping from these controllers. Eigenvalue analysis shows STATCOM shifts modes further into the stable region than SVC. Both STATCOM and SVC integration helps renewable sources by mitigating power quality issues to allow more distributed generation on the grid.
Transient stability in power system is vital to be addressed due to large disturbances that could damage the system such as load changes and voltage increases. This paper presents a multi-machine transient stability using the Static Synchronous Series Compensator (SSSC). SSSC is a device that is connected in series with the power transmission line and produces controllable voltage which contribute to a better performance in the power system stability. As a result, this research has observed a comparison of the synchronization of a three-phase system during single-phase faults before and after installing the SSSC device. In addition, this research investigates the ability of three different types of controllers i.e. Proportional Integral (PI), Proportional Integral Derivation (PID), and Generic controllers to be added to the SSSC improve the transient stability as it cannot operate by itself. This is because the improvement is too small and not able to achieve the desired output. The task presented is to improve the synchronization of the system and time taken for the voltage to stabilize due to the fault. The simulation result shows that the SSSC with an additional controller can improve the stability of a multi-machine power system in a single phase fault.
Comparison of facts devices for two area power system stability enhancement u...IAEME Publication
This document summarizes a research paper that compares the performance of SVC and STATCOM FACTS devices for enhancing transient stability in a two area power system modelled in MATLAB. The paper reviews previous research on using FACTS controllers like SVC, STATCOM, SSSC, TCSC and UPFC to improve power system stability. Simulation results from the paper indicate that a two machine system installed with STATCOM provided better damping of rotor angle oscillations compared to an SVC installation, demonstrating improved transient stability when using a STATCOM.
This paper presents a method to improve transient stability and damping of low frequency oscillations in a multi-machine power system using adaptive neuro-fuzzy control of FACTS devices. A Simulink model of a three generator power system equipped with a UPFC is developed. Simulation results show that a UPFC controlled using an adaptive neuro-fuzzy inference system controller more effectively improves transient stability and damps power oscillations compared to using SSSC. The neuro-fuzzy controller is trained using a hybrid learning algorithm to tune its parameters online based on generator speed deviation and acceleration as inputs.
Static Synchronous Series Compensator (SSSC) with Superconducting Magnetic En...IDES Editor
Static Synchronous Series Compensator (SSSC) has
been designed with Superconducting Magnetic Energy Storage
(SMES) system. A closed loop control scheme has been
proposed with PI controller and real and reactive powers are
taken as references. A 48 pulse voltage source inverter is
designed for the SSSC. Control scheme for the chopper circuit
of SMES coil is also designed. A three area system is taken as
the test system and the operation of SSSC with SMES is
analysed for various transient disturbances. Test results under
different disturbances and operating conditions show the
proposed SSSC with SMES is effective in damping out the
power system oscillations.
This document discusses constraints and load flow analysis in power systems. It outlines four key constraints: active power constraint, reactive power constraint, voltage magnitude constraint, and load angle constraint. It also describes load flow analysis as a balanced mechanism between demand and generation under incremental loading. Load flow analysis is important for the safe and future operation of power systems. The document further discusses bus classification, basic power flow conditions including the proportional relationships between reactive power and voltage and active power and load angle. It also covers the development of the Y-bus matrix considering line resistances and inductances alone and then including line capacitances.
Power Flow Control in Power System Using FACT Device Thyristor Controlled Ser...IOSR Journals
This document summarizes a study on using Flexible AC Transmission System (FACTS) devices for power flow control in a power system. Specifically, it models and simulates the use of Thyristor Controlled Series Capacitor (TCSC) and Static VAR Compensator (SVC) in a two-area, four-machine 11-bus test system using MATLAB/Simulink. TCSC is installed between buses 9 and 10 to reduce line reactance and improve power flow. SVC is installed at bus 9 for voltage control. Simulation results show that TCSC and SVC effectively control active and reactive power flows and bus voltages in the system.
There are two broad classes of power system stability:
1) Steady state stability - The ability of a system to maintain equilibrium after a small disturbance.
2) Transient stability - The ability to maintain synchronism during large disturbances like faults.
Factors influencing transient stability include generator loading, fault conditions, clearing time, reactances, and inertia. Methods to improve it include high-speed excitation, series capacitors, fault clearing and independent pole operation.
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.
FACTS DEVICES AND POWER SYSTEM STABILITY pptMamta Bagoria
This presentation provides an overview of Flexible AC Transmission Systems (FACTS) and power system stability. It defines FACTS as using power electronics to control power flow and enhance transmission system capacity and stability. The document outlines different types of FACTS controllers including series compensation and shunt compensation. It also classifies power system stability into rotor angle stability, voltage stability, and frequency stability and discusses factors that can lead to losses of each type of stability.
Comparison of Multi-Machine Transient Stability Limit Using UPFCIJMTST Journal
The stability of an interconnected power system is compare to normal or stable operation after having been
subjected to some form of disturbance. With interconnected systems continually growing in size and extending
over vast geographical regions, it is becoming increasingly more difficult to maintain synchronism between
various parts of the power system. This paper investigates the comparison of transient stabil ity limit of a
multi-machine power system wi th the help of a UPFC operated in perpendicular vol tage control
mo d e an d t h e i r i t ’ s c omp ar i s o n .
This document provides an overview of power system analysis and stability course content. The course will cover various topics related to power system modeling, analysis, and operation including representation of power systems using one-line diagrams and impedance diagrams, symmetrical and unsymmetrical fault analysis using symmetrical components, and system stability studies. The course will be taught over 35 hours by three subject experts in three weekly sessions, covering each of the five chapters in the textbook.
LOW VOLTAGE RIDE - THROUGH CAPABILITY OF WIND FARMSEditor IJMTER
Nowadays wind turbines are generally required to offer ancillary services similar to those
provided by conventional generators. One of the most important services wind turbines must offer is
to stay connected to the grid in fault situations delivering the reactive current specified in the recent
grid codes. In this paper, FACTS solutions for fixed speed wind farms such as DVR (Dynamic
Voltage Restorer) are presented as well as classic control and crowbar solutions for variable speed
wind turbines.
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.
Controllers For A VSC-HVDC Link Connected To A Weak AC SystemIOSR Journals
This document describes a VSC-HVDC transmission system connecting a strong AC system to a weak island AC system. It investigates the AC filter requirements and designs controllers for the VSC using optimal techniques. The controllers designed are a active power controller for the rectifier, reactive power controller for the rectifier, DC voltage controller for the inverter, and AC voltage controller for the inverter. Simulations are performed in MATLAB to analyze the system's performance for load variations in the island system.
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.
This document discusses Flexible AC Transmission Systems (FACTS) which use power electronics-based devices to improve control of the electric grid and increase power transfer capacity. It covers the history and types of FACTS controllers including series, shunt, and combined configurations. Series controllers inject voltage in series with transmission lines while shunt controllers inject current. FACTS provide benefits like improved power flow control, voltage regulation and transient stability while also involving high costs. Their applications include power flow control, reactive power compensation and improving transmission capability.
Influencing Power Flow and Transient Stability by Static Synchronous Series C...ijeei-iaes
This document summarizes research on using a Static Synchronous Series Compensator (SSSC) to improve power flow and transient stability in a Single Machine Infinite Bus (SMIB) system. The research models an SMIB system and analyzes its power angle curve and transient stability both with and without an SSSC. Results show that the SSSC is effective at stabilizing the system after a transient fault by controlling voltage injection and virtual line impedance. The SSSC allows the system to regain stability faster than without the SSSC. Therefore, the SSSC is concluded to be an effective means of influencing power flow and improving transient stability in power systems.
Flexible Ac Transmission Systems 2Mark Materials and Question BankSanthosh Kumar
The document provides information about Flexible AC Transmission Systems (FACTS) including:
1) FACTS devices use power electronics to control parameters like voltage, impedance, and phase angle to improve power flow in transmission systems.
2) The main objectives of FACTS are to increase power transfer capability and control designated power flow routes.
3) The first STATCOM was implemented in 1955 by TVA to strengthen transmission ties, while the first UPFC was implemented in 1998 by AEP to provide full control of voltage, impedance, and phase angle.
This document discusses power system fault analysis. It begins by outlining the learning objectives and syllabus, which include power flow analysis, power system faults, and power system stability. It then provides an introduction to power system fault analysis, explaining that faults usually occur due to insulation failure, flashover, physical damage or human error. Faults can be three-phase symmetrical or asymmetrical, and involve short-circuits to earth, between phases, or open circuits. Fault analysis is carried out using per-unit quantities. The document goes on to discuss equivalent circuits for single-phase and three-phase systems, and revising per-unit quantities and conversions between different bases.
Stability Modeling Of Storage Devices In FACTS Applicationspreeti naga
The document discusses modeling of storage devices like SMES and BESS for stability applications in FACTS. It describes the need for storage devices to improve controllability in FACTS. It explains SMES, with the superconducting coil producing large fringe fields and power conversion through a VSC and DC-DC chopper. Steady state models are used in power flow studies to maintain real and reactive power injections. State of operation models storage devices as quasi-steady interfaces with dynamic controls. Static VAR compensators are also discussed with thyristor controlled reactors and capacitors to regulate voltage. Dynamic models of the superconducting inductor and battery are also presented.
Unit I - Basic Electrical and Electronics Engineeringarunatshare
This document provides an overview of basic electrical and electronics engineering concepts including circuit components and Ohm's law. It discusses electric current, voltage, power, energy, sources, and basic circuit elements like resistors, inductors, and capacitors. Kirchhoff's laws and different circuit analysis methods like mesh current, node voltage, and source transformation are also introduced. Finally, the document covers electrical measurement techniques and types of instruments.
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 document summarizes a research paper that proposes a method to semantically detect plagiarism in research papers using text mining techniques. It introduces the problem of plagiarism in research and the need for automated detection methods. The proposed method uses TF-IDF to encode documents and LSI for semantic indexing. It collects research papers, preprocesses text, encodes documents with TF-IDF, and indexes them semantically using LSI to find similar papers and detect plagiarism.
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.
FACTS DEVICES AND POWER SYSTEM STABILITY pptMamta Bagoria
This presentation provides an overview of Flexible AC Transmission Systems (FACTS) and power system stability. It defines FACTS as using power electronics to control power flow and enhance transmission system capacity and stability. The document outlines different types of FACTS controllers including series compensation and shunt compensation. It also classifies power system stability into rotor angle stability, voltage stability, and frequency stability and discusses factors that can lead to losses of each type of stability.
Comparison of Multi-Machine Transient Stability Limit Using UPFCIJMTST Journal
The stability of an interconnected power system is compare to normal or stable operation after having been
subjected to some form of disturbance. With interconnected systems continually growing in size and extending
over vast geographical regions, it is becoming increasingly more difficult to maintain synchronism between
various parts of the power system. This paper investigates the comparison of transient stabil ity limit of a
multi-machine power system wi th the help of a UPFC operated in perpendicular vol tage control
mo d e an d t h e i r i t ’ s c omp ar i s o n .
This document provides an overview of power system analysis and stability course content. The course will cover various topics related to power system modeling, analysis, and operation including representation of power systems using one-line diagrams and impedance diagrams, symmetrical and unsymmetrical fault analysis using symmetrical components, and system stability studies. The course will be taught over 35 hours by three subject experts in three weekly sessions, covering each of the five chapters in the textbook.
LOW VOLTAGE RIDE - THROUGH CAPABILITY OF WIND FARMSEditor IJMTER
Nowadays wind turbines are generally required to offer ancillary services similar to those
provided by conventional generators. One of the most important services wind turbines must offer is
to stay connected to the grid in fault situations delivering the reactive current specified in the recent
grid codes. In this paper, FACTS solutions for fixed speed wind farms such as DVR (Dynamic
Voltage Restorer) are presented as well as classic control and crowbar solutions for variable speed
wind turbines.
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.
Controllers For A VSC-HVDC Link Connected To A Weak AC SystemIOSR Journals
This document describes a VSC-HVDC transmission system connecting a strong AC system to a weak island AC system. It investigates the AC filter requirements and designs controllers for the VSC using optimal techniques. The controllers designed are a active power controller for the rectifier, reactive power controller for the rectifier, DC voltage controller for the inverter, and AC voltage controller for the inverter. Simulations are performed in MATLAB to analyze the system's performance for load variations in the island system.
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.
This document discusses Flexible AC Transmission Systems (FACTS) which use power electronics-based devices to improve control of the electric grid and increase power transfer capacity. It covers the history and types of FACTS controllers including series, shunt, and combined configurations. Series controllers inject voltage in series with transmission lines while shunt controllers inject current. FACTS provide benefits like improved power flow control, voltage regulation and transient stability while also involving high costs. Their applications include power flow control, reactive power compensation and improving transmission capability.
Influencing Power Flow and Transient Stability by Static Synchronous Series C...ijeei-iaes
This document summarizes research on using a Static Synchronous Series Compensator (SSSC) to improve power flow and transient stability in a Single Machine Infinite Bus (SMIB) system. The research models an SMIB system and analyzes its power angle curve and transient stability both with and without an SSSC. Results show that the SSSC is effective at stabilizing the system after a transient fault by controlling voltage injection and virtual line impedance. The SSSC allows the system to regain stability faster than without the SSSC. Therefore, the SSSC is concluded to be an effective means of influencing power flow and improving transient stability in power systems.
Flexible Ac Transmission Systems 2Mark Materials and Question BankSanthosh Kumar
The document provides information about Flexible AC Transmission Systems (FACTS) including:
1) FACTS devices use power electronics to control parameters like voltage, impedance, and phase angle to improve power flow in transmission systems.
2) The main objectives of FACTS are to increase power transfer capability and control designated power flow routes.
3) The first STATCOM was implemented in 1955 by TVA to strengthen transmission ties, while the first UPFC was implemented in 1998 by AEP to provide full control of voltage, impedance, and phase angle.
This document discusses power system fault analysis. It begins by outlining the learning objectives and syllabus, which include power flow analysis, power system faults, and power system stability. It then provides an introduction to power system fault analysis, explaining that faults usually occur due to insulation failure, flashover, physical damage or human error. Faults can be three-phase symmetrical or asymmetrical, and involve short-circuits to earth, between phases, or open circuits. Fault analysis is carried out using per-unit quantities. The document goes on to discuss equivalent circuits for single-phase and three-phase systems, and revising per-unit quantities and conversions between different bases.
Stability Modeling Of Storage Devices In FACTS Applicationspreeti naga
The document discusses modeling of storage devices like SMES and BESS for stability applications in FACTS. It describes the need for storage devices to improve controllability in FACTS. It explains SMES, with the superconducting coil producing large fringe fields and power conversion through a VSC and DC-DC chopper. Steady state models are used in power flow studies to maintain real and reactive power injections. State of operation models storage devices as quasi-steady interfaces with dynamic controls. Static VAR compensators are also discussed with thyristor controlled reactors and capacitors to regulate voltage. Dynamic models of the superconducting inductor and battery are also presented.
Unit I - Basic Electrical and Electronics Engineeringarunatshare
This document provides an overview of basic electrical and electronics engineering concepts including circuit components and Ohm's law. It discusses electric current, voltage, power, energy, sources, and basic circuit elements like resistors, inductors, and capacitors. Kirchhoff's laws and different circuit analysis methods like mesh current, node voltage, and source transformation are also introduced. Finally, the document covers electrical measurement techniques and types of instruments.
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 document summarizes a research paper that proposes a method to semantically detect plagiarism in research papers using text mining techniques. It introduces the problem of plagiarism in research and the need for automated detection methods. The proposed method uses TF-IDF to encode documents and LSI for semantic indexing. It collects research papers, preprocesses text, encodes documents with TF-IDF, and indexes them semantically using LSI to find similar papers and detect plagiarism.
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.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document summarizes a research paper that investigates optimally locating SVC and IPFC FACTS devices on the IEEE 30-bus system to reduce power losses and improve voltage profiles under normal, overload, and contingency conditions using Particle Swarm Optimization. The paper presents mathematical models of the SVC and IPFC and describes how PSO is used to determine the optimal location and ratings of the devices. Simulation results show that with optimally located SVC and IPFC, total power losses are reduced and voltage profiles are improved under various system conditions compared to without the FACTS devices.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
1. The document describes a proposed multi-touch table system with RFID technology that could be used in hotels.
2. The system would allow customers to place food orders directly from their table by selecting items on a multi-touch display and authenticating with an RFID card.
3. The table would be connected to backend systems to send orders to the kitchen and deduct amounts from the customer's account.
El documento describe las diferentes secciones y funciones de la aplicación Skype, incluyendo listas de contactos, llamadas y videollamadas recientes, agregar contactos a favoritos, realizar llamadas y videollamadas, realizar llamadas a números móviles si se tiene crédito, e iniciar chats con contactos de Skype.
Una anciana de 80 años quedó viuda y sus hijos debatieron dónde viviría, ya que ninguno podía hacerse cargo de ella. Su nieta de 4 años ofreció que viviera con ella, y así se hizo. Sin embargo, la trataron mal hasta que la nieta dijo que construía una "mesita" para cuando sus padres fueran viejos, haciéndolos darse cuenta de su error. Desde entonces la trataron con respeto.
Las unidades se miden utilizando instrumentos precisos. Los instrumentos más comunes para medir unidades incluyen reglas, cintas métricas y balanzas. Estos instrumentos permiten medir con precisión longitudes, áreas y masas de objetos y materiales.
1) Daniel tenta convencer sua namorada Alessandra a assistir um filme de terror obscuro e raro chamado "Os Demônios da Outra Dimensão".
2) Alessandra relutantemente aceita ir, mas não está animada.
3) Enquanto isso, ela pesquisa sobre o fascínio do medo na universidade e encontra um livro misterioso sobre o filme.
Cliodhna Egan is a student who was born on September 21, 2016 and has the student ID number of 10133632. This brief document appears to contain basic identifying information for an individual named Cliodhna Egan, including their date of birth and student identification number.
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Optimal Location of Statcom for Power Flow ControlIJMER
International Journal of Modern Engineering Research (IJMER) is Peer reviewed, online Journal. It serves as an international archival forum of scholarly research related to engineering and science education.
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Mitigation of Voltage Fluctuations in Power System Using STATCOMIJERA Editor
Wind energy being a renewable source of energy is enjoying a rapid growth globally. However, wind energy being an uncontrollable source of energy coupled with the fact that it uses distributed induction generators for power conversion poses a challenge in integrating a large scale wind-farm into a weak power system. An actual weak power system with two large Wind-Farms (WFs) coupled to it is introduced as part of this study. A model of this integrated system along with a STATCOM for steady state and dynamic impact study is developed in the MATLAB/Simulink environment. The power quality issues are highlighted and a centralized STATCOM is proposed to solve the issue of the voltage fluctuations in particular in addition to addressing the other issues. Based on the results obtained from the simulation, the system voltage control issues are analyzed and the location of STATCOM is assessed. Finally, a STATCOM control strategy for suppression of voltage fluctuations is presented.
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3.application of upfc in multi machine system for transient stability improve...EditorJST
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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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2) A MATLAB/Simulink model of a DSTATCOM power circuit and control system is developed. Simulation results under different load conditions are presented to demonstrate the DSTATCOM's ability to provide power factor correction, harmonic compensation, and reactive power support.
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International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
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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.
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1. Mr.S.B.Dandawate*, Mrs.S.L.Shaikh / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.1383-1387
1383 | P a g e
Analysis of Effect on Transient Stability of Interconnected Power
System by Introduction of HVDC Link.
Mr.S.B.Dandawate*, Mrs.S.L.Shaikh**
*,**(Department of Electrical Engineering, Walchand College of Engineering, Sangli)
ABSTRACT
Modern power employs HVDC links as a
reliable and economical option for long EHVAC
transmission line. The HVDC link in the power
system behaves very differently than
conventional HVAC lines during the disturbances
in the power system. This paper analyses the
effect of HVDC system on the transient stability
of power system. Effect is studied on IEEE 24 bus
reliability test system. A self-sufficient model
developed in MATLAB Simulink has been given
with full details, which can work as a basic
structure for an advanced and detailed study.
Keywords – Transient Stability, HVDC.
I. INTRODUCTION
The improving reliability of supply is one
of the objective to interconnect the generators
located at large distances and the purpose is
achieved by running the synchronous generators in
parallel i.e. in synchronism and with adequate
capacity to meet the load demand [1]. The stability
problem is concerned with the behavior of the
synchronous machines after they have been
perturbed while operating in synchronism. If
perturbation does not involve any net change in
power, the machine should return to the original
state. If unbalance between the supply and load is
created by the change in load, in generation, or in
network conditions, a new operating state is
necessary. In any case all the interconnected
synchronous machines should remain in
synchronism if the system is to be kept stable [2].
Distinction should be made between sudden and
major disturbances, which we shall call large
impacts, and smaller and more normal random
impacts. If one of these large impacts occurs, the
study of system behavior following it is referred to
as the transient stability problem [3]. The system
response to such disturbances involves large
excursions of generator rotor angles, power flows,
bus voltages, and other system variables. The ability
of the system to survive a certain disturbance
depends on its precise operating
condition at the time of the occurrence of
disturbance. A change in the system loading,
generation schedule, network interconnections, or
type of circuit protection may give completely
different results in a stability study for the same
disturbance. Thus the transient stability study is a
very specific one, from which the engineer
concludes that under given system conditions and
for a given impact the synchronous machines will or
will not remain in synchronism [4].
The problem of interest is one where a power
system operating under a steady load condition is
perturbed, causing the readjustment of the voltage
angles of the synchronous machines. Any unbalance
between the generation and load initiates a transient
that causes the rotors of the synchronous machines
to “swing” because net accelerating (or decelerating)
torques are exerted on these rotors. If these net
torques are sufficiently large to cause some of the
rotors to swing far enough so that one or more
machines “slip a pole,” synchronism between the
machines is lost [3].
The transient stability is affected by lots of
components present in power system and its
behavior during the disturbance, like excitation
system of generators, reactive power compensating
devices, circuit breakers and steam valves of turbine.
In this paper the effect of adding the HVDC line in
the power system has been studied. The HVDC line
shows very different behavior under transients than
the HVAC lines as the power flow in DC lines is
independent upon the voltage angles at the both
ends. To study its effect on the transient stability,
24-Bus IEEE Reliability test system has been
simulated in the MATLAB- Simulink environment.
The PMU have been simulated to collect the voltage
angles at the generator terminals and the behavior of
the system is studied from these measurements.
The paper is organized as follows. Section II
details the simulated 24 bus system, Section III gives
the details of PMU and its simulation, Section IV
details HVDC system and its controls. Section V
presents the simulation results, and Section VI
concludes.
II. DESCRIPTION OF THE
BENCHMARK POWER SYSTEM
This section first introduces the models of
the different power system elements of the IEEE
24 bus system that is
2. Mr.S.B.Dandawate*, Mrs.S.L.Shaikh / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.1383-1387
1384 | P a g e
used for the simulations. The fig.1 shows the layout
of it.
Fig. 1:-IEEE Reliability Test system
The system contains 10 plants, one
synchronous condensers and a reactor [5]. They are
interconnected by 230KV network and 138KV
network, both of them are interconnected through
the 5 two winding transformers as shown in fig.1.
The generators inside the plants are assumed to be
coherent generators and considered as a single unit
in the system with capacity equal to addition of
capacities of all units in the plant. The generators are
equipped with AVR’s and PSS. The plants are
considered as the hydro power plants and hence
hydraulic turbine and governor blocks in Simulink
are used to supply mechanical power to it. Fig. 2
below gives the Simulink model of the subsystem
simulated for the plants.
Fig. 2:- Synchronous machine, excitation and
governor subsystem
Following table gives the loading of each generator
–
TABLE 1: - GENERATOR OUTPUTS BEFORE
DISTURBANCE.
Generator
No.
Bus
No.
Real Power
(MW)
Reactive
Power
(MVAr)
1 1 200.02 325.26
2 2 174.98 223.17
3 3 224.96 261.01
4 13 175.22 -196.98
5 15 50.07 -45.35
6 16 50.06 -64.026
7 18 200.17 -31.11
8 21 150.13 -36.033
9 22 100.17 -22.295
10 23 327.86 -91.17
The loads are modeled as a constant impedance load
and hence the power absorbed by them is
proportional to the square of the voltage across
them. System contains a reactor of capacity 100
MVAr at bus 6 and a synchronous condenser of
capacity -200 to 50 MVAr at bus 14.
III. HVDC SYSTEM AND CONTROLLES
HVDC systems are employed in modern
power systems because of numerous economical and
technical advantages over AC transmission when
line length is more. The behavior of the HVDC line
during and after the disturbance is different than the
HVAC line as the power flow of the AC line is
dependent upon the voltage angles at both the ends
of the line while in DC line the power flow
dependent merely upon the AC voltage magnitude at
both ends and can be explained from following
circuit diagram
Fig.3:- Equivalent circuit of HVDC line
The power flow is governed by the equations
(1)
(2)
In the benchmark model one 200KV,
100MW, 100Km single pole CSC based HVDC line
has been added in 230KV network between bus 18
to bus 11. Passive harmonic filters are employed to
absorb the generated harmonics and to supply the
required reactive power for the converter operations
at the rectifier as well as inverter end. Terminal of
the line connected to the bus 18 acts as a rectifier
while connected to bus 11 acts as an inverter. Hence
3. Mr.S.B.Dandawate*, Mrs.S.L.Shaikh / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.1383-1387
1385 | P a g e
the line guides power flow from 230KV network to
138KV network.
Three modes of operation are designed to control the
power injections from the end buses of each HVDC-
link to desired value [6]. Under normal conditions,
the HVDC-links operate in constant power mode
when the rectifier operates in constant current
control and the inverter operates in constant
extinction angle control. During disturbances, when
α reaches extreme values, the mode of operation
changes. The control modes can be written as
follows.
• Mode 1: Constant power/current control at the
rectifier and constant extinction angle at the inverter.
• Mode 2: Minimum firing angle control at the
rectifier and constant power/current control at the
inverter.
• Mode 3: Minimum firing angle control at the
rectifier, and constant extinction control at the
inverter. This is the transition mode between Mode 1
and Mode 2.
HVDC link cannot be started abruptly as it may give
a shock to existing system. The link is programmed
to start and reach a steady state. Then steps are
applied on the reference current of the rectifier and
on the inverter reference voltage in order to execute
the purpose. The converters are deblocked and
started by ramping the rectifier and inverter
reference current. At t = 0.02 s, the reference current
is ramped to reach the minimum value of 0.1 pu in
0.3 s (0.033 pu/s). At the end of this first ramp (t =
0.32 s) the DC line is charged at its nominal voltage
and DC voltage reaches steady-state. At t= 0.4 s, the
reference current is ramped from 0.1 pu to 1 pu
(500A) in 0.18 s (3 pu/s). At the end of this starting
sequence (t=0.54 s) , the DC current reaches steady
state.
IV. PMU IMPLEMENTATION IN SYSTEM
A Phasor Measurement Unit (PMU) is a
device that provides synchrophasor and frequency
measurements for one or more three phase AC
voltage or current waveforms. The PMU takes
reading throughout the system where it has been
installed at the same time and hence we have the
phasors from all across the system at same instant so
it can be compared to study system behavior at that
instant. The device uses CT and PT signals as an
input and samples it N times per cycle of the 50 Hz
(in this case) and by applying DFT we get the
fundamental component of the phasor as
(4)
The conventional phasor representation of the phasor
is releted to the fundamental component as
(5)
The devices are simulated in the Simulink and the
MATLAB code has been generated to calculate the
phasors in Simulink model(Fig.5).
Fig.5:-Simulink model to simulate PMU
The devices are connected at each generator
terminal hence we have the synchronized phasors of
all generator terminals. PMU in this case gives 25
phasors per second as per reference (9). Because of
implementation of DFT technique PMU gives output
of phasor angles between -1800
to +1800
instead of
00
to 3600
(7).
V. SIMULATION AND RESULTS
The Simulink model of the IEEE 24 bus
reliability test system is given in Fig. 6. To study the
transient stability of the model, the disturbance has
been created by applying three phase to ground solid
short circuit to various locations in the power
system. The faults are cleared by opening the
respective transmission lines and the critical clearing
time of each fault for a particular operating condition
of the power system has been noted. The same
exercise is carried out for a system with and without
HVDC link. The behavior of the system is studied
by observing rotor angles of the synchronous
machines. When angles of the machine moves away
from each other by 1800
, it is considered that
stability is lost. PMUs installed at the generator
terminals gives us the voltage angles of the
respective generator terminal voltage. The
assumption have been made that the terminal voltage
angle and rotor angles are same, and hence the
PMUs gives us directly the rotor angles of the
generators. As the time frame of interest in transient
stability analysis is usually three to five seconds
after the disturbance [1], this
study is conducted to the first three seconds after the
short-circuit inception.
4. Mr.S.B.Dandawate*, Mrs.S.L.Shaikh / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.1383-1387
1386 | P a g e
Fig. 6:- Simulink Model of IEEE 24 Bus Test
System.
V.1. Illustrative Example
A three phase to ground fault is applied to
bus 16 at t=1s, and the fault is cleared by tripping
lines 16-14, at t=1.5sec and t=1.7sec without HVDC
link. From the generator angles (Fig.7 and Fig.8) we
can see the system loses synchronism for FCT
0.7sec, the generators 6, 7, 8 and 9 speeds up from
rest of the system. Study is repeated after addition of
HCDC link in Model and the generator rotor angle
movement is observed for FCT 0.7sec (Fig. 9).
Results shows that after inception of HVDC link, the
system does not loses synchronism when fault
cleared at 0.7sec.
Fig.7:- Rotor angles for FCT 0.5 sec, without
HVDC.
Fig.8:- Rotor angles for FCT 0.7 sec, without
HVDC.
Fig.9:- Rotor angles for FCT 0.7 sec, with HVDC.
Same study has been conducted for faults at various
locations in the system and the critical clearing time
has been noted down in Table 2.
TABLE 2:- CRITICAL CLEARING TIME (IN
SEC.) FOR DIFFERENT CONTINGENCIES
Fault
Location
Line
Opened
Critical
FCT
Without
HVDC
(Sec.)
Critical
FCT with
HVDC
(Sec.)
Bus 16 16-17 0.7 1.4
Bus 16 16-14 0.68 1.6
Bus 16 16-17 &
16-14
0.6 2.0
Bus 14 14-11 0.932 3.0
Bus 21 15-21 0.32 0.9
VI. CONCLUSION
Transient stability of the interconnected
5. Mr.S.B.Dandawate*, Mrs.S.L.Shaikh / International Journal of Engineering Research and
Applications (IJERA) ISSN: 2248-9622 www.ijera.com
Vol. 3, Issue 3, May-Jun 2013, pp.1383-1387
1387 | P a g e
power system gets improved with HVDC link
introduced in it. A significant improvement in the
critical fault clearing time is observed when HVDC
link is present. The role of HVDC in transient
stability improvement depends mainly upon the
location and the power rating of HVDC transmission
line. A complete model for transient stability study
of a multi-machine power system was developed
using Simulink. Thus a Simulink model is not only
best suited for an analytical study of a typical power
system network, but it can also incorporate the state-
of-the-art tools for a detailed study and parameter
optimization. A Simulink model is very user
friendly, with tremendous interactive capacity and
unlimited hierarchical model structure.
REFERENCES
[1] W.D Stevensen,J.J.Grainger, Power System
Anlysis (Tata Mcgraw Hill Education, 2003)
[2] P. Kundur,Power System Stability and ControlI
(Tata McGraw Hill Education,2011 )
[3] E.W.Kimbark,Power System Sability Vol
I,II,III, (John Willey , 2003)
[4] P. M. Anderson and A. A. Fouad, Power
System Control and Stability (Iowa State
University Press, Ames, IA, 1977)
[5] A report prepared by the Reliability Test
System Task Force of the Application of
Probability Methods Subcommittee, IEEE
reliability test system, IEEE Transactions on
Power Apparatus and Systems, Vol. PAS-98,
No.6 Nov./Dec. 1979
[6] J. Arrillaga, High Voltage Direct Current
Transmission, (IEE Press Power Engineering
Series, 1883).
[7] A.G.Phadke, J.S. Thorp,Synchronised Phasor
Measurement and Their Applications,(Springer
2008).
[8] A.G.Phadke,J.S.Thorp,M.G.Admaik,A New
Measurement Technique for Tracking Voltage
Phasors,Local System frequency,and Rate of
Change of Frequency,Power Engineering
Review,Vol 2 Issue 5, 1983,0272-1724
[9] IEEE Standard for Synchrophasors for Power
System , IEEE Std 1344-1995(R2001).
BIOGRAPHIES
S. B. Dandawate: Has completed B.E in Electrical
Engineering from University of Pune and doing
M.Tech in Power System in Walchand College of
Engineering, Sangli. His areas of interest are Power
System Stability, Power System Operation and
Control and HVDC Transmission System.
S. L. Shaikh : She is associate Professor in the
faculty of Electrical Engineering in Walchand
College of Engineering Sangli. Her research areas
are power system stability and power quality.