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.
A Fault Detection and Classification Method for SC Transmission Line Using Ph...paperpublications3
Abstract: In this paper, fault detection and classification for Series Compensated Line (SCL) using phasor measurement unit is presented. The algorithm presented in this paper uses the PMU synchronized measurements and not depends on the data to be provided by the electricity utility. The compensated line parameters and Thevenin’s equivalent (TE) of the system at SCL terminals are calculated online, using three independent sets of pre-fault phasor measurements. The accuracy of fault location is performed with respect to fault location/position, types of fault, fault angle. The accuracy of the algorithm is simulated in MATLAB for 9-bus transmission system.
Multi-Machine Stability Using Dynamic Inversion Technique IJECEIAES
Stability studies of multi machine system are a major concern to power system engineers due to the increasing complexity involved. This paper deals with the application of a nonlinear technique called Dynamic Inversion, to TCSC for the improvement of stability of multi-machine system. The transient stability studies for various cases: without any controller, with 75% line compensation and with Dynamic Inversion technique, are compared. The critical clearing time as well as the maximum loading ability is also discussed. The result for the nonlinear controller is found to be better than all the other cases.
Power System State Estimation - A ReviewIDES Editor
The aim of this article is to provide a comprehensive
survey on power system state estimation techniques. The
algorithms used for finding the system states under both static
and dynamic state estimations are discussed in brief. The
authors are opinion that the scope of pursuing research in the
area of state estimation with PMU and SCADA measurements
is the state of the art and timely.
A Comparison Between Two Average Modelling Techniques of AC-AC Power ConvertersIAES-IJPEDS
In this paper, a comparative evaluation of two modelling tools for switching AC-AC power converters is presented. Both of them are based on average modelling techniques. The first approach is based on the circuit averaging technique and consists in the topological manipulations, applied to a converter states. The second approach makes use of a state-space averaged model of the converter and is based on analytical manipulations using the different state representations of a converter. The two modelling techniques are applied to a same AC-AC called matrix-reactance frequency converter based on buck-boost topology. These techniques are compared on the basis of their rapidity, quantity of calculations and transformations and its limitations.
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.
A Fault Detection and Classification Method for SC Transmission Line Using Ph...paperpublications3
Abstract: In this paper, fault detection and classification for Series Compensated Line (SCL) using phasor measurement unit is presented. The algorithm presented in this paper uses the PMU synchronized measurements and not depends on the data to be provided by the electricity utility. The compensated line parameters and Thevenin’s equivalent (TE) of the system at SCL terminals are calculated online, using three independent sets of pre-fault phasor measurements. The accuracy of fault location is performed with respect to fault location/position, types of fault, fault angle. The accuracy of the algorithm is simulated in MATLAB for 9-bus transmission system.
Multi-Machine Stability Using Dynamic Inversion Technique IJECEIAES
Stability studies of multi machine system are a major concern to power system engineers due to the increasing complexity involved. This paper deals with the application of a nonlinear technique called Dynamic Inversion, to TCSC for the improvement of stability of multi-machine system. The transient stability studies for various cases: without any controller, with 75% line compensation and with Dynamic Inversion technique, are compared. The critical clearing time as well as the maximum loading ability is also discussed. The result for the nonlinear controller is found to be better than all the other cases.
Power System State Estimation - A ReviewIDES Editor
The aim of this article is to provide a comprehensive
survey on power system state estimation techniques. The
algorithms used for finding the system states under both static
and dynamic state estimations are discussed in brief. The
authors are opinion that the scope of pursuing research in the
area of state estimation with PMU and SCADA measurements
is the state of the art and timely.
A Comparison Between Two Average Modelling Techniques of AC-AC Power ConvertersIAES-IJPEDS
In this paper, a comparative evaluation of two modelling tools for switching AC-AC power converters is presented. Both of them are based on average modelling techniques. The first approach is based on the circuit averaging technique and consists in the topological manipulations, applied to a converter states. The second approach makes use of a state-space averaged model of the converter and is based on analytical manipulations using the different state representations of a converter. The two modelling techniques are applied to a same AC-AC called matrix-reactance frequency converter based on buck-boost topology. These techniques are compared on the basis of their rapidity, quantity of calculations and transformations and its limitations.
Simulation, bifurcation, and stability analysis of a SEPIC converter control...IJECEIAES
This article presents some results of SEPIC converter dynamics when controlled by a center pulse width modulator controller (CPWM). The duty cycle is calculated using the ZAD (Zero Average Dynamics) technique. Results obtained using this technique show a great variety of non-linear phenomena such as bifurcations and chaos, as parameters associated with the switching surface. These phenomena have been studied in the present paper in numerical form. Simulations were done in MATLAB.
A Novel Direct Torque Control for Induction Machine Drive System with Low Tor...IAES-IJPEDS
The conventional Direct Torque Control (DTC) is known to produce a quick and robust response in AC drives. However, during steady state, stator flux and electromagnetic torque which results in incorrect speed estimations and acoustical noise. A modified Direct Torque Control (DTC) by using Space Vector Modulation (DTC-SVM) for induction machine is proposed in this paper. Using this control strategy, the ripples introduced in torque and flux are reduced. This paper presents a novel approach to design and implementation of a high perfromane torque control (DTC-SVM) of induction machine using Field Programmable gate array (FPGA). The performance of the proposed control scheme is evaluated through digital simulation using Matlab\Simulink and Xilinx System Generator. The simulation results are used to verify the effectiveness of the proposed control strategy.
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
Performance Improvement of Multi Level Inverter fed Vector Controlled Inducti...IJPEDS-IAES
In this paper, the analysis of space vector based multi level inverter (MLI) fed vector controlled induction motor drive for a low speed operation is presented. The performance of indirect field oriented controlled induction motor drive (IMD) is poor with two-level inverter for low speed operations (LSO). The reduction in performance and peak value of torque are mainly due to the non-linearity caused by stator voltage drop and inverter. Hence the performance factors of induction motor drive are analyzed with the multi level inverters under different operating conditions. In this approach, the steady state ripple content in the current and torque waveforms are reduced and that to ripple content of torque is reduced from 0.15 to 0.05 under steady state with five-level inverter. When there is a step change in the load torque, the momentary decrease in speed with five-level inverter is less when compared two and three-level inverters and the speed response reaches the reference value very quickly with five-level inverter during steady state and transient periods. So the overall performance of drive is improved with five- level inverter when compared to two-level and three- level inverters under low speed operations.
State Estimation of Power System with Interline Power Flow ControllerIDES Editor
Now-a-days Flexible A.C. Transmission
System (FACTS) controllers are incorporated into the
power system network to control the power flow and
enhance system stability. Traditional state estimation
methods without integrating FACTS devices will not be
suitable for power systems embedded with FACTS
controller. Based on the conventional power system state
estimation model, a new method is proposed wherein an
IPFC based power injection model is incorporated in the
state estimation algorithm. Interline power flow controller
(IPFC) is one of the versatile FACTS device. The
proposed method is tested on Anderson and Fouad 9-bus
test system and the results are presented.
Open switch fault diagnosis in three phase inverter using diagnostic variable...eSAT Journals
The reliability of power electronics system such as three phase inverter is important in various applications. Different types of faults occur in it, which may influence the operation of system. Such faults require unexpected maintenance, which increases the cost of manufacturing. Therefore fault diagnosis of such devices plays vital role in industry. One possible fault that occurs in inverter is an open switch fault. This paper provides a new technique based on diagnostic variable which detects single as well as multiple open switch fault in three phase inverter. In this method, diagnostic variables are used to detect faulty phase. Along with these diagnostic variables, an average current of three phase inverter is used for the detection of single as well as multiple faulty switches. Key Words: Power electronics, open switch fault, diagnostic variables.
This work presents a study of the three-phase parallel active power filter and the various controllers used in its control. Moreover, in order to improve the quality of electrical energy, by making it conform to the new normative constraints, we have also been led to develop and apply advanced automation methods. In this framework, this paper reports of several regulatory structures : fuzzy logic, PWM, new space vector PWM (NSVPWM), space vector PWM (SVPWM), HYSTERESIS moreover, in order to produce a parallel active filter, a thorough study of experimental feasibility was carried out, taking into account the industrial constraints of the product both in its design and its application.
Wavelet Based Fault Detection, Classification in Transmission System with TCS...IJERA Editor
This paper presents simulation results of the application of distance relays for the protection of transmission systems employing flexible alternating current transmission controllers such as Thyristor Controlled Series Capacitor (TCSC). The complete digital simulation of TCSC within a transmission system is performed in the MATLAB/Simulink environment using the Power System Block set (PSB). This paper presents an efficient method based on wavelet transforms both fault detection and classification which is almost independent of fault impedance, fault location and fault inception angle of transmission line fault currents with FACTS controllers.
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.
Frequency Response Assessment: Parameter Identification of Simplified Governo...Power System Operation
With a growing share of inverter-interfaced generation
in modern power systems, synchronous inertia is
declining. This leads to faster frequency drop after large
generation trip events. During low inertia conditions,
frequency containment reserves might not be sufficient
to arrest frequency before it reaches the threshold for
underfrequency load shedding. It is therefore becoming
increasingly important for system operators to be able to
assess frequency response in near real time. In contrast to
detailed models, simplified models offer short simulation
times and their parameters can be accurately identified
and adapted to changing system conditions in near real
time. In this paper, the parameters of governor response
models are identified by minimizing the error residuals
between the simulation models’ and the actual system’s
measured active power response. This is accomplished
by using historic event data from two system operators:
the Electric Reliability Council Of Texas (ERCOT) and
the Swedish Svenska kraftnät (Svk). Then, the respective
frequency response models are simulated to assess
frequency response. The results show that, despite their
simplicity, the models provide a very good fit compared
to the actual response. The models of ERCOT and
Svk are examined; however, a similar approach can be
employed to represent the frequency response of other
power systems.
PID controller using rapid control prototyping techniquesIJECEIAES
To analyze the performance of the PID controller in a buck type converter implemented in real time. We begin by designing a continuous controller using the analytical method for calculating PIDs. Pulse width modulation is then used and bifurcation diagrams analyzed to reveal some problems of switching and sampling time. The model converter is then implemented with a PID controller in dSPACE. The experimental results provide detailed requirements of sampling frequency and switching speed, and show the performance of the PID controller. Converters are used in power generation solar systems and conmuted power sources for feed telecommunication devices, smart grids, and other applications.
Algorithm for Fault Location and Classification on Parallel Transmission Line...IJECEIAES
This paper proposed a new algorithm for fault location and classification using wavelet based on Clarke’s transformation to obtain the fault current. This novel method of fault current approach is studied by comparing the use of the glide path of the fault voltage. The current alpha and beta (Current Mode) were used to transform the signal using discrete wavelet transform (DWT). The fault location was determined by using the Clarke’s transformation, and then turned into a wavelet, which was very precise and thorough. The most accurate was the mother wavelet Db4 which had the fastest time and smallest error detection when compared with the other wavelet mothers. In this study, the Clarke’s transformation is also compared with the Karenbauer’s, which has produced results with similar error percentage. The simulation results using PSCAD / EMTDC software showed that the proposed algorithm could distinguish internal and external faults to get the current signal in the transformation of a signal fault.
Renewable energy sources are increasingly being used today and solar energy is the most readily and abundantly available energy source. Boost converters are an integral part of any solar energy system. In order to obtain maximum possible energy from the solar system multi-phase interleaved boost converters are used. This paper presents the small-signal ac modelling and closed loop control of three-phase interleaved boost converter. State–space modelling methodology has been adopted to have linearized equivalent model of the boost converter. The interleaved three-phase boost converter is averaged over its one switching period and perturbed with small ac variations and finally linearized around its quiescent point to have a small signal ac model. Type III compensator is employed to improve the frequency response and closed loop control of three-phase boost converter. The controller design procedure is discussed in detail. The effect of right-half plane zero in non-minimum phase system and the appropriate pole-zero placements to overcome the maximum phase lag in such system is discussed. The compensated closed loop system is tested for load variations to observe the transient response.
DAMPING INTER-AREA OSCILLATIONS IN POWER SYSTEMS USING A CDM-BASED PID CONTRO...Power System Operation
The interconnected energy transport system is the
mechanism that provides the stability of energy, or
the balance, between the centers of production and
consumption throughout the country. The
interconnected system adapts energy production to
changes in consumption. For many years, because of
long transmission lines or high-value power
transmission in weak-connected power systems, one
of the problems encountered is the existence of lowfrequency
oscillations between generator groups [1,
2]. These inter-area oscillations are a significant
issue in power system stability and control areas.
Modern power systems possess three main
properties: (1) the measure of interconnected system
is getting larger; (2) there is a closer operating point
to the power system stability limit because of
environmental and economic conditions; (3) being
composed of new elements and keeping pace with
technological developments unfortunately cause new
uncertainties in the stability of power systems. These
properties increase the risk of formation of lowfrequency
oscillations [3].
Optimal Coordination of DOCR for Radial Distribution Systems in Presence of TCSCIJPEDS-IAES
Protective relays coordination is the process of determining the exact relay
settings such that the relay closes to the fault would operates faster than other
relays. The operating time of each relay depends on two independent
variables called Pickup current (Ip) and Time Dial Setting (TDS). In this
paper, a PSO algorithm has been presented to determine the coordination of
Directional Over-Current Relays (DOCRs) in presence of multi-system
FACTS devises. From the simulation result and analysis, the impact of TCSC
location in the in 33-bus distribution system on Directional Over-Current
Relays has been observed on the optimal relays settings as well as the
effectiveness of the proposed algorithm in finding optimal coordination of
directional over-current relays.
Improvise 3-Level DTC of Induction Machine using Constant Switching Frequency...IJPEDS-IAES
This paper presents the advantage of using optimal PI parameter tuning strategy of constant switching method in the three phase Direct torque control (DTC) scheme. The DTC system is known to offer fast decoupled control of torque and flux via a simple control structure. Nevertheless, DTC system has two major drawbacks, which are the variable inverter switching frequency and high torque output ripple. The major factorthat contributes to these problems the usage of hysteresis based comparators to control the output torque. The implementation of PI based constant switching method in DTC able to solve these problems while retaining the simple control structure of conventional DTC. The combination usage of 3-level CHMI in this system can further minimize the output torque ripple by providing greater number of vectors. This paper presents detail explanation and calculationof optimal PI parameter tuning strategyconsecutively to enhance the performance of 3-level DTC system. In order to validate the feasibility, the proposed method compared with convention DTC system via simulation and experiment results.
The effect of rotor disc clearance on the lift performance of contra rotating...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Simulation, bifurcation, and stability analysis of a SEPIC converter control...IJECEIAES
This article presents some results of SEPIC converter dynamics when controlled by a center pulse width modulator controller (CPWM). The duty cycle is calculated using the ZAD (Zero Average Dynamics) technique. Results obtained using this technique show a great variety of non-linear phenomena such as bifurcations and chaos, as parameters associated with the switching surface. These phenomena have been studied in the present paper in numerical form. Simulations were done in MATLAB.
A Novel Direct Torque Control for Induction Machine Drive System with Low Tor...IAES-IJPEDS
The conventional Direct Torque Control (DTC) is known to produce a quick and robust response in AC drives. However, during steady state, stator flux and electromagnetic torque which results in incorrect speed estimations and acoustical noise. A modified Direct Torque Control (DTC) by using Space Vector Modulation (DTC-SVM) for induction machine is proposed in this paper. Using this control strategy, the ripples introduced in torque and flux are reduced. This paper presents a novel approach to design and implementation of a high perfromane torque control (DTC-SVM) of induction machine using Field Programmable gate array (FPGA). The performance of the proposed control scheme is evaluated through digital simulation using Matlab\Simulink and Xilinx System Generator. The simulation results are used to verify the effectiveness of the proposed control strategy.
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
Performance Improvement of Multi Level Inverter fed Vector Controlled Inducti...IJPEDS-IAES
In this paper, the analysis of space vector based multi level inverter (MLI) fed vector controlled induction motor drive for a low speed operation is presented. The performance of indirect field oriented controlled induction motor drive (IMD) is poor with two-level inverter for low speed operations (LSO). The reduction in performance and peak value of torque are mainly due to the non-linearity caused by stator voltage drop and inverter. Hence the performance factors of induction motor drive are analyzed with the multi level inverters under different operating conditions. In this approach, the steady state ripple content in the current and torque waveforms are reduced and that to ripple content of torque is reduced from 0.15 to 0.05 under steady state with five-level inverter. When there is a step change in the load torque, the momentary decrease in speed with five-level inverter is less when compared two and three-level inverters and the speed response reaches the reference value very quickly with five-level inverter during steady state and transient periods. So the overall performance of drive is improved with five- level inverter when compared to two-level and three- level inverters under low speed operations.
State Estimation of Power System with Interline Power Flow ControllerIDES Editor
Now-a-days Flexible A.C. Transmission
System (FACTS) controllers are incorporated into the
power system network to control the power flow and
enhance system stability. Traditional state estimation
methods without integrating FACTS devices will not be
suitable for power systems embedded with FACTS
controller. Based on the conventional power system state
estimation model, a new method is proposed wherein an
IPFC based power injection model is incorporated in the
state estimation algorithm. Interline power flow controller
(IPFC) is one of the versatile FACTS device. The
proposed method is tested on Anderson and Fouad 9-bus
test system and the results are presented.
Open switch fault diagnosis in three phase inverter using diagnostic variable...eSAT Journals
The reliability of power electronics system such as three phase inverter is important in various applications. Different types of faults occur in it, which may influence the operation of system. Such faults require unexpected maintenance, which increases the cost of manufacturing. Therefore fault diagnosis of such devices plays vital role in industry. One possible fault that occurs in inverter is an open switch fault. This paper provides a new technique based on diagnostic variable which detects single as well as multiple open switch fault in three phase inverter. In this method, diagnostic variables are used to detect faulty phase. Along with these diagnostic variables, an average current of three phase inverter is used for the detection of single as well as multiple faulty switches. Key Words: Power electronics, open switch fault, diagnostic variables.
This work presents a study of the three-phase parallel active power filter and the various controllers used in its control. Moreover, in order to improve the quality of electrical energy, by making it conform to the new normative constraints, we have also been led to develop and apply advanced automation methods. In this framework, this paper reports of several regulatory structures : fuzzy logic, PWM, new space vector PWM (NSVPWM), space vector PWM (SVPWM), HYSTERESIS moreover, in order to produce a parallel active filter, a thorough study of experimental feasibility was carried out, taking into account the industrial constraints of the product both in its design and its application.
Wavelet Based Fault Detection, Classification in Transmission System with TCS...IJERA Editor
This paper presents simulation results of the application of distance relays for the protection of transmission systems employing flexible alternating current transmission controllers such as Thyristor Controlled Series Capacitor (TCSC). The complete digital simulation of TCSC within a transmission system is performed in the MATLAB/Simulink environment using the Power System Block set (PSB). This paper presents an efficient method based on wavelet transforms both fault detection and classification which is almost independent of fault impedance, fault location and fault inception angle of transmission line fault currents with FACTS controllers.
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.
Frequency Response Assessment: Parameter Identification of Simplified Governo...Power System Operation
With a growing share of inverter-interfaced generation
in modern power systems, synchronous inertia is
declining. This leads to faster frequency drop after large
generation trip events. During low inertia conditions,
frequency containment reserves might not be sufficient
to arrest frequency before it reaches the threshold for
underfrequency load shedding. It is therefore becoming
increasingly important for system operators to be able to
assess frequency response in near real time. In contrast to
detailed models, simplified models offer short simulation
times and their parameters can be accurately identified
and adapted to changing system conditions in near real
time. In this paper, the parameters of governor response
models are identified by minimizing the error residuals
between the simulation models’ and the actual system’s
measured active power response. This is accomplished
by using historic event data from two system operators:
the Electric Reliability Council Of Texas (ERCOT) and
the Swedish Svenska kraftnät (Svk). Then, the respective
frequency response models are simulated to assess
frequency response. The results show that, despite their
simplicity, the models provide a very good fit compared
to the actual response. The models of ERCOT and
Svk are examined; however, a similar approach can be
employed to represent the frequency response of other
power systems.
PID controller using rapid control prototyping techniquesIJECEIAES
To analyze the performance of the PID controller in a buck type converter implemented in real time. We begin by designing a continuous controller using the analytical method for calculating PIDs. Pulse width modulation is then used and bifurcation diagrams analyzed to reveal some problems of switching and sampling time. The model converter is then implemented with a PID controller in dSPACE. The experimental results provide detailed requirements of sampling frequency and switching speed, and show the performance of the PID controller. Converters are used in power generation solar systems and conmuted power sources for feed telecommunication devices, smart grids, and other applications.
Algorithm for Fault Location and Classification on Parallel Transmission Line...IJECEIAES
This paper proposed a new algorithm for fault location and classification using wavelet based on Clarke’s transformation to obtain the fault current. This novel method of fault current approach is studied by comparing the use of the glide path of the fault voltage. The current alpha and beta (Current Mode) were used to transform the signal using discrete wavelet transform (DWT). The fault location was determined by using the Clarke’s transformation, and then turned into a wavelet, which was very precise and thorough. The most accurate was the mother wavelet Db4 which had the fastest time and smallest error detection when compared with the other wavelet mothers. In this study, the Clarke’s transformation is also compared with the Karenbauer’s, which has produced results with similar error percentage. The simulation results using PSCAD / EMTDC software showed that the proposed algorithm could distinguish internal and external faults to get the current signal in the transformation of a signal fault.
Renewable energy sources are increasingly being used today and solar energy is the most readily and abundantly available energy source. Boost converters are an integral part of any solar energy system. In order to obtain maximum possible energy from the solar system multi-phase interleaved boost converters are used. This paper presents the small-signal ac modelling and closed loop control of three-phase interleaved boost converter. State–space modelling methodology has been adopted to have linearized equivalent model of the boost converter. The interleaved three-phase boost converter is averaged over its one switching period and perturbed with small ac variations and finally linearized around its quiescent point to have a small signal ac model. Type III compensator is employed to improve the frequency response and closed loop control of three-phase boost converter. The controller design procedure is discussed in detail. The effect of right-half plane zero in non-minimum phase system and the appropriate pole-zero placements to overcome the maximum phase lag in such system is discussed. The compensated closed loop system is tested for load variations to observe the transient response.
DAMPING INTER-AREA OSCILLATIONS IN POWER SYSTEMS USING A CDM-BASED PID CONTRO...Power System Operation
The interconnected energy transport system is the
mechanism that provides the stability of energy, or
the balance, between the centers of production and
consumption throughout the country. The
interconnected system adapts energy production to
changes in consumption. For many years, because of
long transmission lines or high-value power
transmission in weak-connected power systems, one
of the problems encountered is the existence of lowfrequency
oscillations between generator groups [1,
2]. These inter-area oscillations are a significant
issue in power system stability and control areas.
Modern power systems possess three main
properties: (1) the measure of interconnected system
is getting larger; (2) there is a closer operating point
to the power system stability limit because of
environmental and economic conditions; (3) being
composed of new elements and keeping pace with
technological developments unfortunately cause new
uncertainties in the stability of power systems. These
properties increase the risk of formation of lowfrequency
oscillations [3].
Optimal Coordination of DOCR for Radial Distribution Systems in Presence of TCSCIJPEDS-IAES
Protective relays coordination is the process of determining the exact relay
settings such that the relay closes to the fault would operates faster than other
relays. The operating time of each relay depends on two independent
variables called Pickup current (Ip) and Time Dial Setting (TDS). In this
paper, a PSO algorithm has been presented to determine the coordination of
Directional Over-Current Relays (DOCRs) in presence of multi-system
FACTS devises. From the simulation result and analysis, the impact of TCSC
location in the in 33-bus distribution system on Directional Over-Current
Relays has been observed on the optimal relays settings as well as the
effectiveness of the proposed algorithm in finding optimal coordination of
directional over-current relays.
Improvise 3-Level DTC of Induction Machine using Constant Switching Frequency...IJPEDS-IAES
This paper presents the advantage of using optimal PI parameter tuning strategy of constant switching method in the three phase Direct torque control (DTC) scheme. The DTC system is known to offer fast decoupled control of torque and flux via a simple control structure. Nevertheless, DTC system has two major drawbacks, which are the variable inverter switching frequency and high torque output ripple. The major factorthat contributes to these problems the usage of hysteresis based comparators to control the output torque. The implementation of PI based constant switching method in DTC able to solve these problems while retaining the simple control structure of conventional DTC. The combination usage of 3-level CHMI in this system can further minimize the output torque ripple by providing greater number of vectors. This paper presents detail explanation and calculationof optimal PI parameter tuning strategyconsecutively to enhance the performance of 3-level DTC system. In order to validate the feasibility, the proposed method compared with convention DTC system via simulation and experiment results.
The effect of rotor disc clearance on the lift performance of contra rotating...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Unit-6: Gyroscope, of Dynamics of machines of VTU Syllabus prepared by Hareesha N Gowda, Asst. Prof, Dayananda Sagar College of Engg, Blore. Please write to hareeshang@gmail.com for suggestions and criticisms.
A robust dlqg controller for damping of sub synchronous oscillations in a ser...eSAT Journals
Abstract This paper investigates the use of Discrete Linear Quadratic Gaussian (DLQG) Compensator to damp sub synchronous oscillations in a Thyrisor Controlled Series Capacitor (TCSC) compensated power system. The study is conducted on IEEE First Benchmark Model (FBM) in which, TCSC is modelled as a discrete linear time-invariant modular unit in the synchronously rotating DQ reference frame. This modular TCSC is then integrated with the Linear Time Invariant (LTI) model of the rest of the system. The design of DLQG includes the design of a Kalman filter for full state estimation and a full state feedback for control. Since the order of the controller is as large as the order of the system considered here(27 states), the practical implementation of the controller is difficult. Hence by using Hankels norm approximation technique, the order of the controller is reduced from 27 to 15 without losing the significant system dynamics. The eigen analysis of the system shows that the use of DLQG can damp torsional oscillations as well as the swing mode oscillations simultaneously, which is practically difficult for a conventional sub-synchronous damping controller. The performance of the system with DLQG is appreciable for all operating conditions and it shows the robustness of the controller. Index Terms: Sub-Synchronous Resonance (SSR), Torsional Oscillations, Thyristor Controlled Series Capacitor (TCSC), Discrete Linear Quadratic Gaussian(DLQG)Compensator, Model Order Reduction (MOR).
A robust dlqg controller for damping of sub synchronous oscillations in a se...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Power System MIMO Identification for Coordinated Design of PSS and TCSC Contr...Reza Pourramezan
Authors: Reza Pourramezan, Sadegh Vaez-Zadeh, and Hamid Reza Nourzadeh
Published in 2007 IEEE Power Engineering Society General Meeting (PES)
DOI: 10.1109/PES.2007.385692
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
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.
In this paper, a detail design and description of a predictive current control scheme are adopted for three-phase grid-connected two-level inverter and its application in wind energy conversion systems. Despite its advantages, the predictive current controller is very sensitive to parameter variations which could eventually affected on system stability. To solve this problem, an estimation technique proposed to identify the value of harmonic filter parameter based on Model reference adaptive system (MRAS). Lyapunov stability theory is selected to guarantee a robust adaptation and stable response over large system parameter variation. The simulation results shows the efficiency of the proposed techniques to improve the current tracking performance.
Design Of Sub Synchronous Damping Controller (SSDC) For TCSC To Improve Power...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.
OPTIMAL TORQUE RIPPLE CONTROL OF ASYNCHRONOUS DRIVE USING INTELLIGENT CONTROL...elelijjournal
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appreciable run-time operation with very simple hysteresis control scheme. Direct control of the torque and flux variables is achieved by choosing suitable inverter voltage space vector from a lookup table. Under varying torque conditions the performance of the drive system is verified using MATLAB/Simulink software tool. The ripple content in the torque parameter is significant when traditional PI controller and Fuzzy approach are configured in the proposed system. Finally, by replacing the PI-Fuzzy controller with Hybrid Controller the torque ripple minimization can be achieved during no-load and loaded conditions.
QFT Based Controller Design of Thyristor-Controlled Phase Shifter for Power S...IJRESJOURNAL
ABSTRACT: This paper presents the automatic design method for a thyristor-controlled phase shifter (TCPS) controller based on quantitative feedback theory (QFT) to improve power system stability in spite of system uncertainties and various disturbances. A genetic algorithm (GA) in a loop shaping state of QFT design has been used to design the TCPS controller satisfying all QFT bounds without repetition of a manual try and error. The proposed performance index in GA has been composed of the QFT bounds and the damping ratio. To verify control performance of the proposed TCPS controller based on QFT using GA, the closed loop eigenvalue and the damping of power system have been analyzed and nonlinear simulations for a single machine infinite bus system have been performed under various disturbances for various operating conditions. The control characteristics of the proposed TCPS controller have been compared with that of the conventional power system stabilizer (PSS) and conventional TCPC controller. The simulation results show that the proposed TCPS controller provided better dynamic responses in comparison with the conventional PSS and TCPS controller.
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.
Performance Analysis and Comparison of Transmission Line Varying the Capacito...ijtsrd
In this paper, performance analysis of transmission line 11 KV with thyristor controlled series capacitor providing stability and power enhancement under the application of PI and PID controllers is compared after varying the capacitance of transmission line capacitor. Simulation results of uncompensated and also for compensated transmission line of 11 KV are compared with PI and PID controllers working with the transmission line system for improving the real power as well as reactive power in the supportive MATLAB environment self tuning is applied through MATLAB PID TUNER for both PID and PI controllers. Sameer Khan | Dr. Aziz Ahmad "Performance Analysis and Comparison of Transmission Line (Varying the Capacitor Value) with (PI and PID) Controllers using TCSC" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-2 , February 2021, URL: https://www.ijtsrd.com/papers/ijtsrd38401.pdf Paper Url: https://www.ijtsrd.com/engineering/electrical-engineering/38401/performance-analysis-and-comparison-of-transmission-line-varying-the-capacitor-value-with-pi-and-pid-controllers-using-tcsc/sameer-khan
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
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11.power flow control limiting short circuit current using tcsc
1. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
Power Flow Control/Limiting Short Circuit Current Using
TCSC
Gannavarapu Akhilesh1* D.Raju2
1. ACTS, JNTU-H, PO box 500035, Hyderabad, Andhra Pradesh, India
2. M.Tech (NIT Nagpur), Hyderabad, Andhra Pradesh, India.
*E-mail of the corresponding author: akkigannavarapu@gmail.com
Abstract
This paper presents the various advantages of Thyristor Controller Series Capacitor (TCSC), both as a Power
Flow Controller, as well as a Short Circuit limiter during faults. The results have been derived and verified
from the software PSCAD, and the graphs and calculations are included in the paper. The results and
information included in the paper are sufficiently accurate.
Keywords: Modelling, power system dynamic stability.
1. Introduction
Thyristor Controlled Series Capacitor (TCSC) is a series FACTS device which allows rapid band continuous
changes of the transmission line impedance. It has great application potential in accurately regulating the
power flow on a transmission line, damping inter-area power oscillations, mitigating sub synchronous
resonance (SSR) and improving transient stability.
The characteristics of a TCSC at steady-state and very low frequencies can be studied using fundamental
frequency analytical models [1], [2]. These particular models recognize the importance of having different
approach from SVC modeling (assuming only line current as a constant) which, although more demanding on
the derivation, gives the most accurate TCSC model.
The fundamental frequency models cannot be used in wider frequency range since they only give the
relationship among fundamental components of variables when at steady-state.
Conventionally, the electromechanical transient programs like EMTP or PSCAD/EMTDC are used for
TCSC transient stability analysis. These simulation tools are accurate but they employ trial and error type
studies only, implying use of a large number of repetitive simulation runs for varying parameters in the case
of complex analysis or design tasks. On the other hand, the application of dynamic systems analysis
techniques or modern control design theories would bring benefits like shorter design time, optimization of
resources and development of new improved designs. In particular, the eigenvalue and frequency domain
analysis are widely recognized tools and they would prove invaluable for system designers and operators.
These techniques however always necessitate a suitable and accurate dynamic system model.
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Vol 3, No 2, 2012
There have been a number of attempts to derive an accurate analytical model of a TCSC that can be employed
in system stability studies and controller design [3]–[6]. The model presented in [3] uses a special form of
discretization, applying Poincare mapping, for the particular Kayenta TCSC installation. The model
derivation for a different system will be similarly tedious and the final model form is not convenient for the
application of standard stability studies and controller design theories especially not for larger systems. A
similar final model form is derived in [4], and the model derivation is improved since direct discretization of
the linear system model is used, however, it suffers other shortcomings as the model in [3]. The modeling
principle reported in [5] avoids discretization and stresses the need for assuming only line current as an ideal
sine, however, it employs rotating vectors that might be difficult to use with stability studies, and only
considers the open loop configuration. The model in [5] is also oversimplified because of the use of
equivalent reactance and equivalent capacitance that might be deficient when used in wider frequency range.
Most of these re- ported models are therefore concerned with a particular system or particular type of study,
use overly simplified approach and do not include control elements or phase-locked loops (PLLs). In this
study, we attempt to derive a suitable linear continuous TCSC model in state-space form. The model should
have reasonable accuracy for the dynamic studies in the sub synchronous range and it should incorporate
common control elements including PLL. To enable flexibility of the model use with different ac systems, the
model structure adopts subsystem units interlinked in similar manner as with SVC modeling [6].
We also seek to offer complete closed-loop model verification in the time and frequency domains.
1.1 Test System
The test system for the study is a long transmission system compensated by a TCSC and connected to a firm
voltage source on each side. Fig. 1 shows a single line diagram of the test system where the transmission line
is represented by a lumped resistance and inductance in accordance with the approach for sub-synchronous
resonance studies [7]. Each phase of the TCSC is composed of a fixed capacitor in parallel with a
thyristor-controlled reactor (TCR). The TCSC is controlled by varying the phase delay of the thyristor firing
pulses synchronized through a PLL to the line current waveform.
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ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
Three different test systems are used in order to verify the model accuracy with different system parameter
and different operating points:
• System 1—75% compensation, capacitive mode;
• System 2—40% compensation, capacitive mode;
• System 3—75% compensation, inductive mode.
The test system parameters are practically selected according to the recommendations in [8]
(regarding and natural resonance) and the test system data are given in the Appendix.
1.2 Fundamental Frequency Model
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4. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
The fundamental frequency model of a TCSC is derived first to enable initialization of the steady-state
parameters. The voltage across the TCSC capacitor comprises an uncontrolled and a controlled component
[8], and it is presumed that the line current is constant over one fundamental cycle in accordance with [1], [2],
[5]. The uncontrolled component is a sine wave (unaffected by thyristor switching) and it is also constant
over a fundamental cycle since it is directly related to the amplitude of the prevailing line current. The
controlled component is a nonlinear variable that depends on circuit variables and on the TCR firing
angle.
In this study, the controlled component is represented as a nonlinear function of the uncontrolled component
and firing angle, as shown in Fig. 2.With this approach, captures the nonlinear phenomena caused by
thyristor switching influence and all internal interactions with capacitor voltage assuming
only that the line current and are linear. We seek in our work to study dynamics of in a wider frequency
range and also to offer a simplified representation for fundamental frequency studies. The fundamental
components of reactor current and the voltages and are selected as state variables and the non- linear
state-space model is presented as
Simulation Circuit for TCSC (500 KV System)
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ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
To derive the corresponding linear model at the nominal frequency, it is postulated that the model has the
structure:
Where and are the unknown model parameters dependent on the firing
angle The above model structure is correct for zero firing angle
Fig 4 : Voltage Phasor Model
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Vol 3, No 2, 2012
( , i.e., full conduction with measured from the voltage crest) and we presume the same
model structure but different parameter values for .
Considering the two components of the thyristor current on the right side of (7) we note that produces
the current that is driven by a constant voltage (over one fundamental cycle) in accordance to the earlier
assumption. As a result, the configuration is similar to the shunt connection of TRC in a SVC, and the
constant can be calculated using the approach of equivalent reactance for the TCR current in a SVC
[6], [8]
In order to determine the constant , we represent (6)–(7) as
a transfer function in the following form:
Observing (10), it is seen that is the resonant frequency of an undamped second order system. The
proposed expression for this frequency is given below in (12) and it is determined using the experimental
frequency response of the model for the nonlinear TCSC segment as presented later in Section 1.3.
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ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
Fig 5: Simulation Circuit for TCSC.
TCSC gain at fundamental frequency is derived
TCSC fundamental frequency impedance is
Where
And is defined in (12).
Compared with the fundamental frequency TCSC model in [1], [2], the derived model (13) is considerably
simpler, yet it will be shown that the accuracy is very similar.
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Vol 3, No 2, 2012
The above model is tested against PSCAD in the following way. The system is operated in open loop, i.e.,
with a fixed reference thyristor firing angle, in the configuration of Fig. 1. The value of the reference thyristor
angle is changed in interval and for each angle the value of the TCSC voltage
is observed. Since all other parameters are constant, the TCSC voltage is directly proportional to the TCSC
impedance and this is an effective way to obtain accurate information on the fundamental TCSC impedance.
Fig. 3 shows the steady-state TCSC voltage against the range of firing angle values, where the above linear
model results are shown as model 2 and also the results from researchers [1], [2] as model 1. It is seen that the
proposed model shows good accuracy across the entire firing angle range and especially the results are very
close to those from [1], [2]. In fact the above model differs negligibly from the model [1], [2], except in the
less used low firing angles in range where the difference is still below 5%. It is also
evident that the two analytical models show small but consistent discrepancy against PSCAD/EMTDC, and
despite all simplifications in PSCAD it was not possible to obtain better matching.
Fig 6: TCSC Power measurement.
1.3 Small-Signal Dynamic Analytical Model
A. TCSC Model
The transfer function in (10) is accurate only at fundamental frequency and it cannot be used for wider
frequency studies. The goal of the dynamic modeling is to derive a dynamic expression for model of
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ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
satisfactory accuracy in the sub-synchronous frequency range and for small signals around the steady-state
operating point
Fig 7: Steady State TCSC voltage for different firing angles.
The steady-state for an AC system variable is a periodic waveform at fundamental frequency with constant
magnitude and phase.
The frequency response is of TCSC is studied assuming that the input voltage is
Where the first sine signal denotes the steady-state operation with all parameters constant.The second term is
the input in the experimental frequency response and it has small magnitude. The output is monitored and
the first harmonic of the Fourier series is compared with the input signal to obtain the frequency response.
If it is assumed that the injected component is small in magnitude compared to the fundamental component,
(as it is case in a small-signal study) the thyristor firing pulses will remain synchronized to the fundamental
component. We can therefore base the study on the following assumptions:
• The firing pulses are regularly spaced (i.e., unaffected by the injected oscillations).
• The conduction period is symmetrical and unaffected by the injected signal.
• The magnitude of the fundamental frequency does not affect frequency response at other frequencies (the
magnitude of fundamental component will be assumed zero in the study and, therefore, does not contain the
fundamental component).
Source generates a sine signal with the above range of frequencies and for each frequency the magnitude and
phase of the first harmonic of the output voltage is observed.
The pulse generator produces equally spaced conduction intervals that are based on the fundamental
frequency period and which are dependent on the firing angle. Based on the above assumption, these firing
instants are unaffected by the injection signal.
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Vol 3, No 2, 2012
Test System (500 KV Transmission Line)
Power flow in 500KV line.
TCSC in Capacitive Mode
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TCSC in Inductive Mode:
Power flow with TCSC in Inductive Mode
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B. Model Connections
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1.4 Test Results
Power Flow and Line Current under fault without TCSC.
Here the fault is applied at 0.2 sec and cleared at 0.4 sec.
Power Flow and Line current under fault with TCSC
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ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
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Here the fault is applied at 1.5 sec and cleared at 2.5 sec.
Plot: X (TCSC) versus firing angle in Inductive mode.
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ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
Plot: X (TCSC) versus firing angle in Capacitive mode.
1.5 Conclusion
TCSC is placed on a 500kV, long transmission line, to improve power transfer. Without the TCSC the power
transfer is around 110MW, as seen during the first 0.5s of the simulation when the TCSC is bypassed. The
TCSC is modeled as a voltage source using equivalent impedance at fundamental frequency in each phase.
The nominal compensation is 75%, i.e. assuming only the capacitors (firing angle of 90deg). The natural
oscillatory frequency of the TCSC is 163Hz, which is 2.7 times the fundamental frequency.
The TCSC can operate in capacitive or inductive mode, although the latter is rarely used in practice.
Since the resonance for this TCSC is around 58deg firing angle, the operation is prohibited in firing angle
range 49deg - 69deg. Note that the resonance for the overall system (when the line impedance is included) is
around 67deg. The capacitive mode is achieved with firing angles 69-90deg. The impedance is lowest at
90deg, and therefore power transfer increases as the firing angle is reduced. In capacitive mode the range for
impedance values is approximately 120-136 Ohm. This range corresponds to approximately 500MW power
transfer range. Comparing with the power transfer of 110 MW with an uncompensated line, TCSC enables
significant improvement in power transfer level.
TCSC reduces the short circuit current from 350amp to 250amp under three phase short circuit fault.
So TCSC significantly reduces the short circuit current.
References
Dragan Jovcic and G. N. Pillai, “Analytical Modelling of TCSC Dynamics”, IEEE Transactions on Power
Delivery, VOL 20, No.2, APRIL 2005
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16. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
S. G. Jalali, R. A. Hedin, M. Pereira, and K. Sadek, “A stability model for the advanced series compensator
(ASC),” IEEE Trans. Power Del., vol. 11, no. 2, pp. 1128–1137, Apr. 1996.
C. R. Fuerte-Esquivel, E. Acha, and H. Ambriz-Perez, “A thyristor controlled series compensator model for
the power flow solution of practical power networks,” IEEE Trans. Power Syst., vol. 9, no. 15, pp.
58–64,Feb. 2000.
D. Jovcic, N. Pahalawaththa, M. Zavahir, and H. Hassan, “SVC dynamic analytical model,” IEEE Trans.
Power Del., vol. 18, no. 4, pp.1455–1461, Oct. 2003.
G. Akhilesh from Hyderabad, born on 6th January, 1990. Currently pursuing Bachelor of Technology, in
Electrical and Electronic Engineering, from ACTS, JNTU, Hyderabad, India. Previously published the paper
titled “Fuzzy Logic Scheme for Speed Control of Induction Motor”, ICCA ’12.
D.Raju Pursued M.Tech from National Institute of Technology, Nagpur. Currently pursuing Ph.D from
National Institute of Technology, Nagpur.
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17. Innovative Systems Design and Engineering www.iiste.org
ISSN 2222-1727 (Paper) ISSN 2222-2871 (Online)
Vol 3, No 2, 2012
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18. International Journals Call for Paper
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