This document summarizes research on using a Distribution Static Compensator (DSTATCOM) to enhance power quality in a distribution system network. It begins by describing common power quality issues like voltage sags and how DSTATCOM can help mitigate them. It then provides details on the components of a DSTATCOM including the voltage source converter, controller, and instantaneous current component theory for control. Simulations are presented showing that a DSTATCOM is effective at mitigating voltage sags and fluctuations caused by load and line disturbances. The conclusions are that DSTATCOM is an efficient means of compensating for power quality issues from distributed energy resources on distribution grids.
Mitigation of Fault in the Distribution System by using Flexible Distributed ...IJMER
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.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
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.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
MITIGATION OF UNBALANCED FAULTS IN DISTRIBUTION SYSTEM USING FD-STATCOM WITH ...Suganthi Thangaraj
Power quality is certainly a major concern in the present era. This paper proposes a flexible D-STATCOM with a new controller scheme. And it supplies power to sensitive loads under Islanding conditions. This paper introduces the performance of FD-STATCOM system to mitigate power quality problems under all types of system related disturbances such as L-L &DLG faults. A 12 pulse IGBT based D-STATCOM is designed using MATLAB. Here the super capacitor is used as the storage device. The realibility of the control scheme in the system response to the voltage disturbances caused by LL&DLG faults and Islanded operating conditions are obviously proved in the simulation results.
Mitigation of Fault in the Distribution System by using Flexible Distributed ...IJMER
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.
International Journal of Modern Engineering Research (IJMER) covers all the fields of engineering and science: Electrical Engineering, Mechanical Engineering, Civil Engineering, Chemical Engineering, Computer Engineering, Agricultural Engineering, Aerospace Engineering, Thermodynamics, Structural Engineering, Control Engineering, Robotics, Mechatronics, Fluid Mechanics, Nanotechnology, Simulators, Web-based Learning, Remote Laboratories, Engineering Design Methods, Education Research, Students' Satisfaction and Motivation, Global Projects, and Assessment…. And many more.
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.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
MITIGATION OF UNBALANCED FAULTS IN DISTRIBUTION SYSTEM USING FD-STATCOM WITH ...Suganthi Thangaraj
Power quality is certainly a major concern in the present era. This paper proposes a flexible D-STATCOM with a new controller scheme. And it supplies power to sensitive loads under Islanding conditions. This paper introduces the performance of FD-STATCOM system to mitigate power quality problems under all types of system related disturbances such as L-L &DLG faults. A 12 pulse IGBT based D-STATCOM is designed using MATLAB. Here the super capacitor is used as the storage device. The realibility of the control scheme in the system response to the voltage disturbances caused by LL&DLG faults and Islanded operating conditions are obviously proved in the simulation results.
Mitigation of Voltage Imbalance in A Two Feeder Distribution System Using IupqcIJMERJOURNAL
ABSTRACT: Proliferation of electronic equipment in commercial and industrial processes has resulted in increasingly sensitive electrical loads to be fed from power distribution system which introduce contamination to voltage and current waveforms at the point of common coupling of industrial loads. The unified power quality conditioner (UPQC) is connected between two different feeders (lines), hence this method of connection of the UPQC is called as Interline UPQC (IUPQC).This paper proposes a new connection for a UPQC to improve the power quality of two feeders in a distribution system. Interline Unified Power Quality Conditioner (IUPQC), specifically aims at the integration of series VSC and Shunt VSC to provide high quality power supply by means of voltage sag/swell compensation, harmonic elimination in a power distribution network, so that improved power quality can be made available at the point of common coupling. The structure, control and capability of the IUPQC are discussed in this paper. The efficiency of the proposed configuration has been verified through simulation using MATLAB/ SIMULINK.
A Review of Matrix Converter and Novel Control Method of DC-AC Matrix Converteridescitation
For the past three decades, research work in matrix
converter has increased much. This paper presents a new
topology of DC-AC matrix converter, starting with a brief
historical review of different modulation and control strategies
which was developed recently. The purpose of the Paper is to
generate a multilevel output voltage equal to multilevel
inverter with reduced switches. An important part of the paper
is to design a dedicated DC-AC matrix converter and some
new arrays of bidirectional switches in a single module are
also presented. To find the performance of the module the
entire module is designed with MATLAB simulation and tested
with three phase induction motor.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Simulation and Comparison of DVR and DSTATCOM Used for voltage sag mitigation...paperpublications3
Abstract: Power Quality problem in a system leads to various disturbances such as voltage fluctuations, transients and waveform distortions that results in a mis-operation or a failure of end user equipment. There are different types of custom power devices like Distribution Static Compensator (D-STATCOM) and Dynamic Voltage Restorer (DVR) which can effectively use for mitigation of different type of power quality problems. This paper describes the technique of correcting the supply voltage sag distributed system and also describes performance comparison are presented between DVR and DSTATCOM to know how both the devices successfully been applied to power system for regulating system voltage effectively. DSTATCOM and DVR both of them based on VSI principle. A DVR is a series compensation device which injects a voltage in series with system and a DSTATCOM is a shunt compensation device which injects a current into the system to correct the power quality problems. This paper presents a power system operation with PI controller with abc to dq0 convertor approach. Total Harmonics Distortion (THD) is also calculated for the system with and without compensation. Results are presented to assess the performance of devices as a potential custom power solution. Improve dynamic voltage control and thus increase system load ability. This paper presents modeling and simulation of DVR & DSTATCOM in MATLAB/Simulink.
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.
SRF CONTROLLED DVR FOR COMPENSATION OF BALANCED AND UNBALANCED VOLTAGE DISTUR...IAEME Publication
The growth of power electronictechnology in the field of electric power sector has caused a greater awarenesson the power quality of distribution systems. With the re-structuring of powersystems and with shifting trend towards distributed and dispersed generation,the issue of power quality is going to take newer dimensions. The presentresearch is to identify the prominent concerns in this area and hence themeasures that can enhance the quality of power. This paper investigates theproblems of voltage sag, swell and its severe impact on nonlinear loads,sensitive loads.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Stability Enhancement of Pleiku Power System using a Distribution Static Sync...IJAEMSJORNAL
This paper presents the simulation results of using a static synchronous compensator (D-STATCOM) based on voltage source converter (VSC) to enhance voltage stability and improve the stability of the actual Pleiku Power System. The PI controller based D-STATCOM is applied to stabilize and improve voltage waveforms at load buses in the studied power system under three-phase short circuit fault. Simulation results in a time domain are presented to show effectiveness of using the D-STATCOM for stability and improvement of voltage quality when small disturbances occur, and of enhancing voltage magnitude, mitigating voltage oscillation in transient conditions under a severe disturbance in the power system.
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.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
Mitigation of Voltage Imbalance in A Two Feeder Distribution System Using IupqcIJMERJOURNAL
ABSTRACT: Proliferation of electronic equipment in commercial and industrial processes has resulted in increasingly sensitive electrical loads to be fed from power distribution system which introduce contamination to voltage and current waveforms at the point of common coupling of industrial loads. The unified power quality conditioner (UPQC) is connected between two different feeders (lines), hence this method of connection of the UPQC is called as Interline UPQC (IUPQC).This paper proposes a new connection for a UPQC to improve the power quality of two feeders in a distribution system. Interline Unified Power Quality Conditioner (IUPQC), specifically aims at the integration of series VSC and Shunt VSC to provide high quality power supply by means of voltage sag/swell compensation, harmonic elimination in a power distribution network, so that improved power quality can be made available at the point of common coupling. The structure, control and capability of the IUPQC are discussed in this paper. The efficiency of the proposed configuration has been verified through simulation using MATLAB/ SIMULINK.
A Review of Matrix Converter and Novel Control Method of DC-AC Matrix Converteridescitation
For the past three decades, research work in matrix
converter has increased much. This paper presents a new
topology of DC-AC matrix converter, starting with a brief
historical review of different modulation and control strategies
which was developed recently. The purpose of the Paper is to
generate a multilevel output voltage equal to multilevel
inverter with reduced switches. An important part of the paper
is to design a dedicated DC-AC matrix converter and some
new arrays of bidirectional switches in a single module are
also presented. To find the performance of the module the
entire module is designed with MATLAB simulation and tested
with three phase induction motor.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Simulation and Comparison of DVR and DSTATCOM Used for voltage sag mitigation...paperpublications3
Abstract: Power Quality problem in a system leads to various disturbances such as voltage fluctuations, transients and waveform distortions that results in a mis-operation or a failure of end user equipment. There are different types of custom power devices like Distribution Static Compensator (D-STATCOM) and Dynamic Voltage Restorer (DVR) which can effectively use for mitigation of different type of power quality problems. This paper describes the technique of correcting the supply voltage sag distributed system and also describes performance comparison are presented between DVR and DSTATCOM to know how both the devices successfully been applied to power system for regulating system voltage effectively. DSTATCOM and DVR both of them based on VSI principle. A DVR is a series compensation device which injects a voltage in series with system and a DSTATCOM is a shunt compensation device which injects a current into the system to correct the power quality problems. This paper presents a power system operation with PI controller with abc to dq0 convertor approach. Total Harmonics Distortion (THD) is also calculated for the system with and without compensation. Results are presented to assess the performance of devices as a potential custom power solution. Improve dynamic voltage control and thus increase system load ability. This paper presents modeling and simulation of DVR & DSTATCOM in MATLAB/Simulink.
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.
SRF CONTROLLED DVR FOR COMPENSATION OF BALANCED AND UNBALANCED VOLTAGE DISTUR...IAEME Publication
The growth of power electronictechnology in the field of electric power sector has caused a greater awarenesson the power quality of distribution systems. With the re-structuring of powersystems and with shifting trend towards distributed and dispersed generation,the issue of power quality is going to take newer dimensions. The presentresearch is to identify the prominent concerns in this area and hence themeasures that can enhance the quality of power. This paper investigates theproblems of voltage sag, swell and its severe impact on nonlinear loads,sensitive loads.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Stability Enhancement of Pleiku Power System using a Distribution Static Sync...IJAEMSJORNAL
This paper presents the simulation results of using a static synchronous compensator (D-STATCOM) based on voltage source converter (VSC) to enhance voltage stability and improve the stability of the actual Pleiku Power System. The PI controller based D-STATCOM is applied to stabilize and improve voltage waveforms at load buses in the studied power system under three-phase short circuit fault. Simulation results in a time domain are presented to show effectiveness of using the D-STATCOM for stability and improvement of voltage quality when small disturbances occur, and of enhancing voltage magnitude, mitigating voltage oscillation in transient conditions under a severe disturbance in the power system.
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.
We follow "Rigorous Publication" model - means that all articles appear on IJERD after full appraisal, effectiveness, legitimacy and reliability of research content. International Journal of Engineering Research and Development publishes papers online as well as provide hard copy of Journal to authors after publication of paper. It is intended to serve as a forum for researchers, practitioners and developers to exchange ideas and results for the advancement of Engineering & Technology.
Simulation of D-STATCOM to study Voltage Stability in Distribution systemijsrd.com
This paper presents the simulation of D-statcom to understand the improvement of voltage stability [1] of distribution system. The power circuits of the D-STATCOM and distribution networks are made up of simpower system blocks, while the control circuits made with the simulink blocks The STATCOM is applied to regulate transmission voltage to allow greater power flow in a voltage limited transmission network, in the same manner as a static var compensator (SVC), the STATCOM has further potential by giving an inherently faster response and greater output to a system with depressed voltage and offers improved quality of supply. The main applications of the STATCOM are; Distribution STATCOM (D-STATCOM) exhibits high speed control of reactive power to provide voltage stabilization and other type of system control. The DSTATCOM protects the utility transmission or distribution system from voltage sag and /or flicker caused by rapidly varying reactive current demand. During the transient conditions the D-STATCOM provides leading or lagging reactive power to active system stability, power factor correction and load balancing.
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.
1.compensation of reactive power using d statcom in grid interfaced pv systemEditorJST
This paper displays the upgrade of voltage droops, Harmonic mutilation and low power figure utilizing Distribution Static Compensator (D-STATCOM) with LCL Passive Filter in Distribution Framework. At whatever point there is an entrance of photovoltaic cell energy to the low voltage appropriated matrix, there happen the issue of confuse in voltage and recurrence in the system, maybe brought on by non-direct loads, creating music. The model depends on the Voltage Source Converter (VSC) guideline. The D-STATCOM infuses a current into the framework to alleviate the voltage lists. LCL Passive Filter Was then added to D-STATCOM to enhance symphonies bending and low power figure. The reproductions were performed utilizing MATLAB SIMULINK.
A Review on Optimization Techniques for Power Quality Improvement using DSTAT...ijtsrd
As demand for electricity has risen exponentially, power production and transmission are affected by scarce energy, environmental constraints and other losses. Soft computing methods to fix the sag, swell and disruption of the supply voltage in the distributed device. At present, a broad variety of highly versatile controls that leverage on newly available power electronics components are evolving for custom power applications. Control electronic equipment intended to improve the stability and efficiency of electricity flows in low voltage distribution networks. The control algorithm is used to derive the fundamental weighted value of the active and reactive power components. Using a digital signal processor, DSTATCOM is built and its output as a DSTATCOM is found to be satisfactory for different types of loads. Amit Radhakrishna Parhad | Pramod Kumar Rathore "A Review on Optimization Techniques for Power Quality Improvement using DSTATCOM (Neural Network Approach)" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd42403.pdf Paper URL: https://www.ijtsrd.comengineering/electrical-engineering/42403/a-review-on-optimization-techniques-for-power-quality-improvement-using-dstatcom-neural-network-approach/amit-radhakrishna-parhad
CONTROL OF BATTERY OPERATED SYSTEM WITH A DC-DC BOOSTCONVERTER FED DSTATCOM U...ijiert bestjournal
This paper presents a comprehensive survey of DSTATCOM control strategies put forward recently. It is
aimed at providing a broad perspective on the status of DSTATCOM control methods to researchers and
application engineers dealing with harmonic suppression issues. Many control techniques have been
designed, developed, and realized for active filters in recent years. The proposed DSTATCOM consists of a
three-leg Voltage Source Converter (VSC) with a dc bus capacitor. The PV array or battery operated boost
converter is proposed to maintain the dc link voltage of the dc bus capacitor for continuous compensation
for the load. This paper presents to evaluate the performance comparison of two control strategies for
extracting the reference currents to control the proposed DSTATCOM. The two control methods are
Synchronous Reference Frame (SRF) theory and IcosΦ algorithm. The performance of the DSTATCOM is
validated using MATLAB software with its simulink and Power System Block set (PSB) toolboxes. The
simulation results for the two control methods are compared to validate the superior performance of the
IcosΦ algorithm.
Voltage profile Improvement Using Static Synchronous Compensator STATCOMINFOGAIN PUBLICATION
Static synchronous compensator (STATCOM) is a regulating device used in AC transmission systems as a source or a sink of reactive power. The most widely utilization of the STATCOM is in enhancing the voltage stability of the transmission line. A voltage regulator is a FACTs device used to adjust the voltage disturbance by injecting a controllable voltage into the system. This paper implement Nruro-Fuzzy controller to control the STATCOM to improve the voltage profile of the power network. The controller has been simulated for some kinds of disturbances and the results show improvements in voltage profile of the system. The performance of STATCOM with its controller was very close within 98% of the nominal value of the busbar voltage.
This paper focus on distribution system by applying different control techniques in order to improve the performance of the system. In the distribution system mainly concentrate on power quality issues like reactive power control, harmonic elimination, power factor correction, etc. Because of power quality problems voltage, current, frequency are continuously changing in power systems. These changes will effects the performance of power systems. Power quality problems can be compensated by placing DSTATCOM which is connected at PCC in parallel. It is shunt connected VSI along with the filters, with the help of DSTATCOM voltage sag, swell and THD can be controlled. This paper presents detailed explanation about performance and configuration of latest control techniques to control the DSTATCOM.
Power Quality Enhancement in Power System Network using DSTACOM
1. International Journal of Engineering Inventions
e-ISSN: 2278-7461, p-ISSN: 2319-6491
Volume 2, Issue 6 (April 2013) PP: 57-62
www.ijeijournal.com Page | 57
Power Quality Enhancement in Power System Network using
DSTACOM
Dr. P. Chandra Sekhar
Associate Professor, Department of Electrical and Electronics Engineering,
MGIT, Hyderabad, (A.P), India.
Abstract: A problem in Power system network is an occurrence characterized by a nonstandard voltage,
current or frequency that results in a failure or a mis-operation of end user equipments. Utility distribution
networks, sensitive industrial loads and critical commercial operations suffer from various types of outages and
service interruptions which can cost significant financial losses. With the restructuring of power systems and
with shifting trend towards distributed and dispersed generation, the issue of power quality is going to take
newer dimensions. In developing countries like India, where the variation of power frequency and many such
other determinants of power quality are themselves a serious question, it is very vital to take positive steps in
this direction .The present work is to identify the prominent concerns in this area and hence the measures that
can enhance the quality of the power are recommended. This paper presents the enhancement of voltage sags
using Distribution Static Compensator (DSTATCOM) in distribution system. The model is based on the Voltage
Source Converter (VSC) principle. The D-STATCOM injects a current into the system to mitigate the voltage
sags. The simulations were performed using MATLAB SIMULINK version R2007b.Voltage sags are mitigated.
Keywords: D-STATCOM, Voltage Sags, Voltage Source Converter (VSC).
I. INTRODUCTION
One of the most common power quality problems today is voltage dips. A voltage dip is a short time
(10 ms to 1 minute) event during which a reduction in r.m.s voltage magnitude occurs. It is often set only by two
parameters, depth/magnitude and duration. The voltage dip magnitude is ranged from 10% to 90% of nominal
voltage (which corresponds to 90% to 10% remaining voltage) and with a duration from half a cycle to 1 min. In
a three-phase system a voltage dip is by nature a three-phase phenomenon, which affects both the phase-to-
ground and phase-to-phase voltages. A voltage dip is caused by a fault in the utility system, a fault within the
customer‟s facility or a large increase of the load current, like starting a motor or transformer energizing.
Typical faults are single-phase or multiple-phase short circuits, which leads to high currents. The high current
results in a voltage drop over the network impedance. At the fault location the voltage in the faulted phases
drops close to zero, whereas in the non-faulted phases it remains more or less unchanged [1, 2].
Voltage dips are one of the most occurring power quality problems. Off course, for an industry an
outage is worse, than a voltage dip, but voltage dips occur more often and cause severe problems and
economical losses. Utilities often focus on disturbances from end-user equipment as the main power quality
problems. This is correct for many disturbances, flicker, harmonics, etc., but voltage dips mainly have their
origin in the higher voltage levels. Faults due to lightning, is one of the most common causes to voltage dips on
overhead lines. If the economical losses due to voltage dips are significant, mitigation actions can be profitable
for the customer and even in some cases for the utility. Since there is no standard solution which will work for
every site, each mitigation action must be carefully planned and evaluated. There are different ways to mitigate
voltage dips, swell and interruptions in transmission and distribution systems. At present, a wide range of very
flexible controllers, which capitalize on newly available power electronics components, are emerging for custom
power applications [3, 4]. Among these, the distribution static compensator and the dynamic voltage restorer are
most effective devices, both of them based on the VSC principle.
STATCOM is often used in transmission system. When it is used in distribution system, it is called D-
STATCOM(STATCOM in Distribution system). D-STATCOM is a key FACTS controller and it utilizes
power electronics to solve many power quality problems commonly faced by distribution systems. Potential
applications of D-STATCOM include power factor correction, voltage regulation, load balancing and harmonic
reduction. Comparing with the SVC, the D-STATCOM has quicker response time and compact structure. It is
expected that the D-STATCOM will replace the roles of SVC in nearly future D-STATCOM and STATCOM
are different in both structure and function, while the choice of control strategy is related to the main-circuit
structure and main function of compensators [3], so D-STATCOM and STATCOM adopt different control
strategy. At present, the use of STATCOM is wide and its strategy is mature, while the introduction of D-
STATCOM is seldom reported. Refer to the strategies for STATCOM, in this paper; a compound control
strategy used in D-STATCOM is presented to achieve the purpose of rapid-response compensation. A PWM-
2. Power Quality Enhancement in Power System Network using DSTACOM
www.ijeijournal.com Page | 58
based control scheme has been implemented to control the electronic valves in the two-level VSC used in the D-
STATCOM [5, 10].
II. DISTRIBUTION STATIC COMPENSATOR (D-STATCOM)
A D-STATCOM consists of a two-level VSC, a dc energystorage device, controller and a coupling
transformer connected in shunt to the distribution network. Figure 2.1 shows the schematic diagram of D-
STATCOM.
Referring to the equation 2.2, output current, Iout will correct the voltage sags by adjusting the voltage
drop across the system impedance, (Zth=R+jX). It may be mention that the effectiveness of D-STATCOM in
correcting voltage sags depends on:
a) The value of Impedance, Zth= R+jX
b) The fault level of the load bus
Figure2.1. Schematic diagram of a D-STATCOM
A. Voltage Source Converter (VSC)
A voltage-source converter is a power electronic device that connected in shunt or parallel to the
system. It can generate a sinusoidal voltage with any required magnitude, frequency and phase angle. The VSC
used to either completely replace the voltage or to inject the „missing voltage‟. The „missing voltage‟ is the
difference between the nominal voltage and the actual. It also converts the DC voltage across storage devices
into a set of three phase AC output voltages [8, 9]. In addition, D-STATCOM is also capable to generate or
absorbs reactive power. If the output voltage of the VSC is greater than AC bus terminal voltages, D-
STATCOM is said to be in capacitive mode. So, it will compensate the reactive power through AC system and
regulates missing voltages. These voltages are in phase and coupled with the AC system through the reactance
of coupling transformers. Suitable adjustment of the phase and magnitude of the DSTATCOM output voltages
allows effectives control of active and reactive power exchanges between D-STATCOM and AC system. In
addition, the converter is normally based on some kind of energy storage, which will supply the converter with a
DC voltage [10].
B. Controller
Figure 2.2 shows the block diagram of Controller system. The controller system is partially part of
distribution system. Proportional-integral controller (PI Controller) is a feedback controller which drives the
system to be controlled with a weighted sum of the error signal (difference between the output and desired set
3. Power Quality Enhancement in Power System Network using DSTACOM
www.ijeijournal.com Page | 59
point) and the integral of that value. In this case, PI controller will process the error signal to zero. The load
r.m.s voltage is brought back to the reference voltage by comparing the reference voltage with the r.m.s voltages
that had been measured at the load point. It also is used to control the flow of reactive power from the DC
capacitor storage circuit. PWM generator is the device that generates the Sinusoidal PWM waveform or signal.
Figure 2.2.Block Diagram of Controller System
To operate PWM generator, the angle is summed with the phase angle of the balance supply voltages
equally at 120 degrees. Therefore, it can produce the desired synchronizing signal that required. PWM generator
also received the error signal angle from PI controller. The modulated signal is compared against a triangle
signal in order to generate the switching signals for VSC valves.
C. Instantaneous Current Component (id-iq) Theory
The Modified Synchronous Frame method is presented in [7]. It is called the instantaneous current
component (id-iq) method. This is similar to the SRF frame method. The transformation angle is now obtained
with the voltages of the ac network. The major difference is that, due to voltage harmonics and imbalance, the
speed of the reference frame is no longer constant. It varies instantaneously depending of the waveform of the
three phase voltage system. In this method the compensating currents are obtained from the instantaneous active
and reactive current components and of the nonlinear load. In the same way, the mains voltages V(a,b,c) and the
polluted currents il(a,b,c) in α-β components must be calculated as given by (2), where C is Clarke
Transformation Matrix. However, the load current components are derived from a synchronous reference frame
based on the Park transformation, where represents the instantaneous voltage vector angle (3).
Figure.2.3 Principal of the synchronous reference frame method
Fig. 2.3 shows the block diagram SRF method. Under balanced and sinusoidal mains voltage
conditions angle θ is a uniformly increasing function of time. This transformation angle is sensitive to voltage
harmonics and unbalance; therefore dθ/dt may not be constant over a mains period. With transformation (2) and
(3) the direct voltage component is
4. Power Quality Enhancement in Power System Network using DSTACOM
www.ijeijournal.com Page | 60
III. MATLAB/SIMULINK MODELING AND SIMULATION RESULTS
Fig. 4 shows the Matlab/Simulink model of distribution system with DSTATCOM. Fig.5 shows the
internal view of DSTATCOM. In this paper simulation is carried out in two cases. In case one we have
considered load disturbance means sudden change of reactive load without DSTATCOM and with
DSTATCOM. In case two we have considered line disturbance like single line to ground fault (SLG), without
DSTATCOM and with DSTATCOM.
Figure. 3 Matlab/Simulink Model of DSTATCOM
Figure. 4 DSTATCOM Internal view
5. Power Quality Enhancement in Power System Network using DSTACOM
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A Case One
Fig. 5 shows the three phase voltage and three phase currents and RMS value of one line voltage. Here
at t=0.2 sec a inductive load is switched ON the line voltage fall from1 P.U to 0.8 P.U
Figure. 5 Simulation results without DSTATCOM
Fig. 6 shows the RMS value of one line voltage with DSTATCOM. Here at t=0.2 sec a inductive load
is switched ON the line voltage fall from1 P.U to 0.98 P.U
Figure. 6 Simulation results with DSTATCOM
B Case two
Fig. 7 shows RMS value of line voltage. Here at t=0.2 sec a SLG fault is created the line voltage fall
from1 P.U to 0.78 P.U.
Figure. 7 Simulation results without DSTATCOM
6. Power Quality Enhancement in Power System Network using DSTACOM
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Fig. 8 shows the RMS value of line voltage with DSTATCOM. Here at t=0.2 sec a SLG fault is created
the line voltage fall from1 P.U to 0.98 P.U
Figure. 8 Simulation results with DSTATCOM
IV. CONCLUSION
DSTATCOM system is an efficient mean for mitigation of PQ disturbances introduced to the grid by
DERs. DSTATCOM compensator is a flexible device which can operate in current control mode for
compensating voltage variation, unbalance and reactive power and in voltage control mode as a voltage
stabilizer. The latter feature enables its application for compensation of dips coming from the supplying
network. The simulation results show that the voltage sags can be mitigate by inserting D-STATCOM to the
distribution system. The same analysis can be carried out for Double Line to Ground (DLG) fault and Three
Line to Ground (TLG) fault also.
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