call for papers, research paper publishing, where to publish research paper, journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJEI, call for papers 2012,journal of science and technolog
This document summarizes a research paper about using an algorithm and dynamic voltage restorer (DVR) to mitigate voltage sags in power systems. It begins with an abstract that describes focusing on using a DVR with an algorithm to control static series compensators without time delay using p-q-r coordinate transformation. It then provides background on voltage sags and defines them. The main body describes the structure and operating principle of a DVR system, including using a rectifier, inverter, filter and PWM control. It presents the mathematical model for calculating voltage sags based on source and fault impedances. The conclusion is that the DVR injects the missing voltage to maintain the load voltage during sags.
IRJET- Mollification Parameter Control by Dynamic Voltage Restorer (DVR)
The document discusses using a Dynamic Voltage Restorer (DVR) to mitigate voltage sags. A DVR is a series-connected device that uses power electronics to quickly restore load voltage to pre-fault levels during voltage sags. It works by injecting the missing voltage back into the system. A DVR consists of an inverter, filter, booster transformer, DC storage such as capacitors, and control system. It monitors the voltage and injects only the amount needed to compensate for the sag using pulse width modulation of the inverter. This allows it to restore the voltage quickly and improve power quality for sensitive loads affected by voltage sags.
DESIGN OF A PROGRAMMABLE LOW POWER LOW DROP-OUT REGULATOR
A low power programmable low drop-out regulator capable of providing 1V output has been proposed. The
regulator requires a supply voltage of 1.2V and works in the temperature range of -40 to 125 °C in nominal
corner (i.e, normal doping for PMOS and NMOS Field Effect Transistors), yielding a load regulation of
3%. The output voltage level is controlled externally by means of 2 1-bit control signals. The circuit
provides a DC gain of 30 dB and a maximum DC Power Supply Rejection Ratio of -35 dB and a worst case
PSRR of -20 dB. Power dissipation in the load is nearly 100 μW
IRJET- Comparison of Power Dissipation in Inverter using SVL Techniques
This document compares the power dissipation of different inverter circuit designs including static CMOS, domino, and domino with self-controllable voltage level (SVL) techniques. It finds that an upper SVL domino circuit has the lowest power consumption of 25.167 μW, which is 35.88% less than a static CMOS inverter. SVL techniques like upper and lower SVL help reduce leakage power by increasing threshold voltage. Simulation results in a 90nm technology show that an upper SVL domino inverter has lower power dissipation and propagation delay compared to other designs.
During Damping of Low Frequency Oscillations in Power Systems with Fuzzy UPFC...
This document summarizes a research paper about using an adaptive neuro-fuzzy controller for a unified power flow controller (UPFC) to damp low frequency oscillations (LFO) in a power system.
The key points are:
1. LFO can occur in power systems due to a lack of damping torque. Traditionally, power system stabilizers were used but FACTS devices like UPFC can also control power flow and provide damping.
2. An adaptive neuro-fuzzy controller is designed for the UPFC to damp LFO. The controller has 2 inputs of deviation in rotor angle and deviation in frequency. Simulation results show it provides good damping performance.
3. The performance of the neuro-fuzzy
This paper presents investigation and performance analysis of novel down sampling based clamping SV PWM technique for diode and cascaded Multi-level Invereter fed to Induction motor drive. A novel down sampling based clamping SVPWM has developed by adding triangular off set to sinusoidal fundamental waveform is modified by down sampling the reference wave by order of 10 so this technique is called clamping space vector pulse width modulation techniques such as PD, POD and APOD. so as to shift the lower order harmonics to higher order side. This novel carrier is compared with the offset injected space vector reference waveform to generate the required PWM pulses to the inverter. To analyze the performance of the proposed PWM technique it is implemented on seven level diode and cascaded Multi-level Inverter using Matlab/Simulink software tool for output line, phase voltage, currents, speed, torque and Total harmonic distortion analysis.
This document presents a novel fast-acting PI controller for regulating the dc-link voltage of a DSTATCOM (distribution static compensator). A DSTATCOM is used to mitigate power quality issues and compensate for nonlinear loads. Conventionally, a PI controller is used but has slow transient response. The paper proposes a fast-acting dc-link voltage controller based on the energy of the dc-link capacitor. It provides mathematical equations to design the gains of the conventional PI controller to achieve similar fast transient response as the proposed controller. Detailed simulations in MATLAB validate that the proposed controller has improved transient performance during load variations compared to the conventional controller.
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.
Compensation of Balanced and Unbalanced Voltage Disturbance using SRF Control...IRJET Journal
This document discusses using a dynamic voltage restorer (DVR) controlled by synchronous reference frame (SRF) theory to compensate for balanced and unbalanced voltage sags and swells in a distribution system. The DVR injects voltage to maintain the load voltage at a constant level during disturbances. It is modeled and simulated in MATLAB/Simulink. Simulation results demonstrate the DVR successfully compensates for various balanced disturbances including single sag/swell events and multiple sag/swell occurrences. The DVR provides compensation by injecting the appropriate compensating voltage as determined by the SRF control scheme.
A Versatile Control Scheme For Dynamic Voltage Restorer To Limit Downstream F...IJERA Editor
The Dynamic Voltage Restorer (DVR) is a custom power device utilized to counteract voltage sags. It injects
controlled three-phase ac voltages in series with the supply voltage, subsequent to voltage sag, to enhance
voltage quality by adjusting the voltage magnitude, wave shape, and phase angle. The DVR is conventionally
bypassed during a downstream fault to prevent potential adverse impacts on the fault and to protect the DVR
components against the fault current. This paper proposes an augmented control strategy for the DVR that
provides:1) voltage-sag compensation under balanced and unbalanced conditions and 2) a fault current
interruption (FCI) function. This paper introduces and evaluates an auxiliary control strategy for downstream
fault current interruption in a radial distribution line by means of a dynamic voltage restorer (DVR). The
proposed controller supplements the voltage-sag compensation control of the DVR. It does not require phaselocked
loop and independently controls the magnitude and phase angle of the injected voltage for each phase.
Fast least error squares digital filters are used to estimate the magnitude and phase of the measured voltages and
effectively reduce the impacts of noise, harmonics, and disturbances on the estimated phasor parameters, and
this enables effective fault current interrupting even under arcing fault conditions. The performance of the DVR
for fault current interruption is analyzed by using MATLAB/SIMULINK software.
IRJET- Mollification Parameter Control by Dynamic Voltage Restorer (DVR)IRJET Journal
The document discusses using a Dynamic Voltage Restorer (DVR) to mitigate voltage sags. A DVR is a series-connected device that uses power electronics to quickly restore load voltage to pre-fault levels during voltage sags. It works by injecting the missing voltage back into the system. A DVR consists of an inverter, filter, booster transformer, DC storage such as capacitors, and control system. It monitors the voltage and injects only the amount needed to compensate for the sag using pulse width modulation of the inverter. This allows it to restore the voltage quickly and improve power quality for sensitive loads affected by voltage sags.
DESIGN OF A PROGRAMMABLE LOW POWER LOW DROP-OUT REGULATORVLSICS Design
A low power programmable low drop-out regulator capable of providing 1V output has been proposed. The
regulator requires a supply voltage of 1.2V and works in the temperature range of -40 to 125 °C in nominal
corner (i.e, normal doping for PMOS and NMOS Field Effect Transistors), yielding a load regulation of
3%. The output voltage level is controlled externally by means of 2 1-bit control signals. The circuit
provides a DC gain of 30 dB and a maximum DC Power Supply Rejection Ratio of -35 dB and a worst case
PSRR of -20 dB. Power dissipation in the load is nearly 100 μW
IRJET- Comparison of Power Dissipation in Inverter using SVL TechniquesIRJET Journal
This document compares the power dissipation of different inverter circuit designs including static CMOS, domino, and domino with self-controllable voltage level (SVL) techniques. It finds that an upper SVL domino circuit has the lowest power consumption of 25.167 μW, which is 35.88% less than a static CMOS inverter. SVL techniques like upper and lower SVL help reduce leakage power by increasing threshold voltage. Simulation results in a 90nm technology show that an upper SVL domino inverter has lower power dissipation and propagation delay compared to other designs.
During Damping of Low Frequency Oscillations in Power Systems with Fuzzy UPFC...IJMER
This document summarizes a research paper about using an adaptive neuro-fuzzy controller for a unified power flow controller (UPFC) to damp low frequency oscillations (LFO) in a power system.
The key points are:
1. LFO can occur in power systems due to a lack of damping torque. Traditionally, power system stabilizers were used but FACTS devices like UPFC can also control power flow and provide damping.
2. An adaptive neuro-fuzzy controller is designed for the UPFC to damp LFO. The controller has 2 inputs of deviation in rotor angle and deviation in frequency. Simulation results show it provides good damping performance.
3. The performance of the neuro-fuzzy
This paper presents investigation and performance analysis of novel down sampling based clamping SV PWM technique for diode and cascaded Multi-level Invereter fed to Induction motor drive. A novel down sampling based clamping SVPWM has developed by adding triangular off set to sinusoidal fundamental waveform is modified by down sampling the reference wave by order of 10 so this technique is called clamping space vector pulse width modulation techniques such as PD, POD and APOD. so as to shift the lower order harmonics to higher order side. This novel carrier is compared with the offset injected space vector reference waveform to generate the required PWM pulses to the inverter. To analyze the performance of the proposed PWM technique it is implemented on seven level diode and cascaded Multi-level Inverter using Matlab/Simulink software tool for output line, phase voltage, currents, speed, torque and Total harmonic distortion analysis.
This document presents a novel fast-acting PI controller for regulating the dc-link voltage of a DSTATCOM (distribution static compensator). A DSTATCOM is used to mitigate power quality issues and compensate for nonlinear loads. Conventionally, a PI controller is used but has slow transient response. The paper proposes a fast-acting dc-link voltage controller based on the energy of the dc-link capacitor. It provides mathematical equations to design the gains of the conventional PI controller to achieve similar fast transient response as the proposed controller. Detailed simulations in MATLAB validate that the proposed controller has improved transient performance during load variations compared to the conventional controller.
This document discusses how MOSFET power losses affect power supply efficiency. It provides equations to calculate the various power loss components in a buck converter, including conduction losses, switching losses, and static losses. MOSFET switching losses are affected by load current and switching frequency. Both the high-side and low-side MOSFETs contribute conduction, switching and gate driver losses. Optimizing MOSFET selection involves tradeoffs between conduction resistance, gate charge and switching speed. Understanding these loss factors enables improved power supply efficiency design.
An Adaptive Zero Voltage Mechanism for Boost ConverterIOSR Journals
This document describes an adaptive zero voltage mechanism proposed for a boost converter. The mechanism uses a variable frequency operation with a single switch instead of multiple switches to reduce size and improve efficiency. It achieves zero voltage switching to reduce switching losses and stresses. The control circuit uses PI control and adaptive feedback to maintain a constant output voltage despite input voltage or load variations. Simulation results show the converter successfully outputs a regulated 60V from a 40V input with the adaptive mechanism matching the resonant and switching frequencies for stability.
This document discusses the design and analysis of a multi-level D-STATCOM to improve power quality. A D-STATCOM is a shunt connected custom power device that can regulate voltage and compensate for reactive power and current harmonics. The paper proposes using a cascaded H-bridge multilevel inverter for the D-STATCOM due to its advantages of low harmonic distortion and reduced switching losses. Simulation results using Matlab/Simulink show that the D-STATCOM is able to regulate the voltage and compensate for reactive power drawn by a non-linear diode rectifier load, improving the power factor and eliminating total harmonic distortion.
International Refereed Journal of Engineering and Science (IRJES)irjes
The core of the vision IRJES is to disseminate new knowledge and technology for the benefit of all, ranging from academic research and professional communities to industry professionals in a range of topics in computer science and engineering. It also provides a place for high-caliber researchers, practitioners and PhD students to present ongoing research and development in these areas.
Thd minimization of modular multilevel converter with unequal dc valuesGhazal Falahi
Different modulation techniques used to control multilevel converters can be classified based on the selected converter topology and optimization goals. Among all proposed modulation methods low switching frequency modulation techniques are very popular for multilevel converters yet non-real time low switching frequency methods cannot be applied to multilevel converters with unequal or varying DC values because these modulation techniques rely on look up tables and the size of look up tables will be huge in this case. This paper proposes a new modular multilevel converter (MMC) structure with unequal DC values. Some well-known low switching frequency modulation techniques and the commonly used PWM based methods are compared and using the new low switching frequency modulation technique called minimal total harmonic distortion (THD) modulation for MMC with unequal DC values is proposed. The PSCAD simulation results show that the new converter topology with unequal DC values has much lower THD compared to the typical MMC. Modulation algorithm is implemented in digital signal processor (DSP) and controller hardware in the loop (CHIL) implementation in RTDS verifies the real-time performance of the algorithm.
Fuzzy Logic Controller Based ZVT-ZCT PWM Boost Converter Using Renewable Ener...IOSR Journals
The document describes a novel ZVT-ZCT-PWM boost converter that uses an active snubber cell to achieve soft switching of the main switch. Key features include:
1) The main switch turns on with zero voltage transition (ZVT) and turns off with zero current transition (ZCT), achieving soft switching.
2) All semiconductor devices operate with soft switching, reducing switching losses.
3) The converter has a simple structure with minimum components and is easy to control.
4) Simulation results for a 2.3kW, 100kHz boost converter show the output voltage can reach 400V with an overall efficiency of 97.8% at nominal power.
The Analysis of Dead Time on Switching Loss in High and Low Side MOSFETs of Z...IDES Editor
This work is about the analysis of dead time variation
on switching losses in a Zero Voltage Switching (ZVS)
synchronous buck converter (SBC) circuit. In high frequency
converter circuits, switching losses are commonly linked with
high and low side switches of SBC circuit. They are activated
externally by the gate driver circuit. The duty ratio, dead time
and resonant inductor are the parameters that affect the
efficiency of the circuit. These variables can be adjusted for
the optimization purposes. The study primarily focuses on
varying the settings of input pulses of the MOSFETs in the
resonant gate driver circuit which consequently affects the
performance of the ZVS synchronous buck converter circuit.
Using the predetermined inductor of 9 nH, the frequency is
maintained at 1 MHz for each cycle transition. The switching
loss graph is obtained and switching losses for both S1 and S2
are calculated and compared to the findings from previous
work. It has shown a decrease in losses by 13.8 % in S1. A dead
time of 15 ns has been determined to be optimized value in
the SBC design.
BP_2010_05_High Eff Low Profile ACDC Power_SMappus May 2010_Edit SMSteve Mappus
Maximizing efficiency in low-profile power supply designs is challenging. A 300W, 1.75" high power supply design uses an interleaved dual boundary conduction mode power factor correction stage followed by an asymmetrical half-bridge DC-DC converter to achieve over 90% efficiency. Careful component selection, topology choice, and control scheme optimization are required to meet the goals of high efficiency over a wide load range while minimizing size and heat sinks in the power supply's restricted form factor.
Design consideration of an mmc hvdc system based on 4500 v:4000a emitter turn...Ghazal Falahi
Excessive power loss is a major concern in high voltage and high power applications and is considered one of the main drawbacks of VSC-HVDC system when compared with traditional HVDC system based on thyristor technology. This is primarily caused by high switching loss associated with switching devices used in the VSC-HVDC. This issue can be largely addressed by using the emerging MMC-HVDC topology, which requires much lower switching frequency than traditional VSC-HVDC. Emitter turn-off thyristor (ETO) is one of the best high power switching devices packed with many advanced features. ETO thyristor based MMC-HVDC system is therefore an extremely attractive choice for ultra-high voltage and high power HVDCs. This paper discusses the operation principle of ETO based MMC-HVDC as well as its design and loss comparison with other solutions.
The document presents a new robust load frequency controller for a two area interconnected power system to reduce deviations in frequency and tie line power due to different load disturbances. It develops a dynamic model of the system using integral control and evaluates the system responses. Simulation results in MATLAB/Simulink are provided to study the impact of changing parameters like inertia constant, integration constant, and turbine constant on the frequency deviation and tie line power flow deviation.
This document discusses the application of synchronized phasor measurement in real-time wide-area monitoring. It provides an overview of phasor and synchrophasor measurement techniques using Fourier transforms. It also discusses power system stability and transient stability. The document demonstrates the monitoring of a multi-machine system using synchronized phasor measurements by simulating various fault conditions and load changes on a 3-machine, 9-bus system and observing the results with a phasor measurement unit to analyze stability.
The document proposes a new VLSI architecture for DSSS signal acquisition that uses Galois sequences. It summarizes that the proposed architecture provides improved signal acquisition at low SNR compared to existing architectures. The key blocks are a Galois sequence generator and QPSK modulation/demodulation. Simulation results on MATLAB and FPGA show the architecture requires low power and complexity while achieving comparatively better low SNR signal acquisition.
This document summarizes and compares various scheduling algorithms used in cloud computing environments. It begins with an introduction to cloud computing and the need for scheduling algorithms in cloud environments. It then describes several existing scheduling algorithms, including compromised-time-cost scheduling, particle swarm optimization-based heuristic, improved cost-based algorithm, resource-aware scheduling, innovative transaction intensive cost-constraint scheduling, scalable heterogeneous earliest-finish-time algorithm, and multiple QoS constrained scheduling strategy of multi-workflows. These algorithms aim to optimize metrics such as execution time, cost, deadline, load balancing, and quality of service. The document concludes by comparing the different scheduling strategies.
Take Control of Your Website for PR Pros! PRSA Southeast District ConferenceCaitlin Jeansonne
Is your PR expertise being trumped by marketing specialists? You can regain control of your website by becoming skilled in the basics of website analytics and SEO. With this knowledge, you will have more control over your website strategy. This session covers how to use web analytics to analyze your current performance, what benchmarks you should use, and which statistics you should focus on. You’ll learn how to research and identify your target audience and to discover what search terms they use to find you. You’ll get a basic introduction to SEO, with understandable explanations of how search engines work.
Material Segurudad Social Y Reforma Compendio 2Tomas Lefever
El documento propone medidas para aumentar la cobertura y densidad de cotizaciones en Chile, incluyendo subsidios para la contratación de trabajadores jóvenes y la obligatoriedad de cotizar para trabajadores independientes. Se estima que estas medidas beneficiarán a cerca de 1,3 millones de personas de bajos ingresos. Se establecen detalles como los montos de subsidios, los plazos de su entrega y sanciones por su percepción indebida.
This document discusses the use of geogrid reinforcement to improve the stability of waste dumps in surface coal mines. It presents the results of both numerical modeling and physical modeling of waste dumps with and without geogrid reinforcement. The numerical modeling found that factors of safety increased with the addition of geogrid layers, from 0.97 without geogrid to 1.11 with two layers. The physical modeling validated these results, showing increased failure angles (dump stability) with geogrids. Thus, the study demonstrates that geogrid reinforcement can enable the construction of more stable, higher waste dumps in coal mines.
This document summarizes a study that evaluates the performance of the urban water sector in Surat City, India using a sustainability index approach. A sustainability index was calculated based on social, economic, environmental, and engineering criteria. Data was collected from the Surat Municipal Corporation and experts were interviewed. The results showed that Surat City has a moderate sustainability index of 0.396. The engineering criteria scored lowest at 0.031, indicating room for improvement in that area. The study provides information on weaknesses in the system and approaches to enhance sustainability of urban water management in Surat City.
O documento descreve como usuários podem monetizar seus perfis no Facebook usando o aplicativo Top Seller da Lomadee. O aplicativo permite que usuários ganhem dinheiro por meio de cliques em anúncios ou comissões de vendas de produtos anunciados em seus perfis. O documento então explica o processo de cadastro no aplicativo Top Seller e configuração para gerar posts patrocinados nos perfis do Facebook.
Similar to call for papers, research paper publishing, where to publish research paper, journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJEI, call for papers 2012,journal of science and technolog
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Implementation of Fuzzy Controlled Photo Voltaic Fed Dynamic Voltage Restorer...ijfls
Power Quality(PQ) has become an area of concern in the electrical distribution system. Dynamic Voltage
Restorer(DVR) restores load voltage to a nominal balanced sinusoidal voltage, when the source voltage
has harmonic distortions, sag, swell and unbalances. In this paper a Photo Voltaic(PV) fed DVR is
proposed to mitigate PQ problems. The PV system can supply the maximum power to the load at a
particular operating point known as Maximum Power Point (MPP), at which the entire PV system operates
with maximum efficiency. A Fuzzy Controller based MPPT is implemented to generate the optimal voltage
from the photovoltaic system by modulating the duty cycle applied to the boost converter. The DVR is
implemented using a Fuzzy Logic Controller based voltage source inverter with Photovoltaic system. The
test system has been simulated and the efficacy of the proposed PV based Fuzzy controlled DVR is
compared with Proportional Integral (PI) controlled DVR.
IMPLEMENTATION OF FUZZY CONTROLLED PHOTO VOLTAIC FED DYNAMIC VOLTAGE RESTORER...Wireilla
Power Quality(PQ) has become an area of concern in the electrical distribution system. Dynamic Voltage Restorer(DVR) restores load voltage to a nominal balanced sinusoidal voltage, when the source voltage has harmonic distortions, sag, swell and unbalances. In this paper a Photo Voltaic(PV) fed DVR is proposed to mitigate PQ problems. The PV system can supply the maximum power to the load at a particular operating point known as Maximum Power Point (MPP), at which the entire PV system operates with maximum efficiency. A Fuzzy Controller based MPPT is implemented to generate the optimal voltage from the photovoltaic system by modulating the duty cycle applied to the boost converter. The DVR is implemented using a Fuzzy Logic Controller based voltage source inverter with Photovoltaic system. The test system has been simulated and the efficacy of the proposed PV based Fuzzy controlled DVR is compared with Proportional Integral (PI) controlled DVR.
Mitigation of Voltage Sag/Swell with Fuzzy Control Reduced Rating DVRIJERD Editor
Power quality has been an issue that is becoming increasingly pivotal in industrial electricity
consumers point of view in recent times. Modern industries employ Sensitive power electronic equipments,
control devices and non-linear loads as part of automated processes to increase energy efficiency and
productivity. Voltage disturbances are the most common power quality problem due to this the use of a large
numbers of sophisticated and sensitive electronic equipment in industrial systems is increased. This paper
discusses the design and simulation of dynamic voltage restorer for improvement of power quality and
reduce the harmonics distortion of sensitive loads. Power quality problem is occurring at non-standard
voltage, current and frequency. Electronic devices are very sensitive loads. In power system voltage sag,
swell, flicker and harmonics are some of the problem to the sensitive load. The compensation capability
of a DVR depends primarily on the maximum voltage injection ability and the amount of stored
energy available within the restorer. This device is connected in series with the distribution feeder at
medium voltage. A fuzzy logic control is used to produce the gate pulses for control circuit of DVR and the
circuit is simulated by using MATLAB/SIMULINK software.
Contemporary Control of DG Integrated DVR for Sag, Swell and Harmonic Mitigat...IJECEIAES
This paper presents a novel control strategy to control DG integrated DVR (dynamic voltage restorer) for mitigation voltage quality problems. Power quality is the most concerning areas in power engineering and voltage quality is of prime focus. Voltage sag, voltage swell and harmonics in voltage causes deterioration in quality of voltage delivered to load. A minor disturbance in voltage profile can degrade the performance of load. Dynamic voltage restorer is a quick responsive custom power device for voltage quality improvement. Photovoltaic (PV) system is considered as DG and output voltage of PV system is boosted with a boost converter to support voltage source converter of DVR. DG integrated DVR with novel control strategy for mitigation of voltage sag, swell and voltage harmonic is presented in this paper. The power system model with DG integrated DVR is developed and results are obtained using MATLAB/SIMULINK. Results are discussed during pre and post sag/swell condition with compensation and THD in voltage is maintained within nominal values.
To Diminish the Voltage Sag Replaced DVR with Generalized Modulation Strategy...IRJET Journal
This document discusses replacing a conventional Dynamic Voltage Restorer (DVR) with a matrix converter to compensate for voltage sags. A DVR injects voltage to maintain the load voltage during disturbances. Conventional DVRs use bulky AC-DC-AC converters. The proposed model replaces this with a matrix converter to avoid energy storage and allow for higher power density. A matrix converter directly converts AC to AC using bi-directional switches. It can compensate for voltage sags and swells more efficiently than a conventional DVR without energy storage limitations. Simulation results show the DVR with matrix converter effectively regulates voltage during faults.
The document discusses inverted sine pulse width modulation (ISPWM) techniques for power quality enhancement with custom power devices. ISPWM generates lower voltage total harmonic distortion compared to conventional sinusoidal PWM. ISPWM has been implemented on a distribution static compensator (DSTATCOM) and dynamic voltage restorer (DVR) to reduce harmonic distortion. Simulation results using MATLAB Simulink show the effectiveness of ISPWM in reducing total harmonic distortion compared to sinusoidal PWM. The key components and operating principles of DSTATCOM and DVR are also summarized.
This document summarizes the design and simulation of a Dynamic Voltage Restorer (DVR) using Sinusoidal Pulse Width Modulation (SPWM). A DVR is a series connected device that compensates for voltage sags and swells in distribution systems. The document describes the components of a DVR including injection transformers, a capacitor bank, voltage source inverter, and passive filters. It also explains how d-q-0 transformation is used to detect voltage sags and calculate the compensating voltage. Simulation results in MATLAB/Simulink show a DVR successfully compensating for a 50% voltage sag over 0.2 seconds using d-q control theory and SPWM pulses to the inverter switches.
The document describes a proposed control scheme for a dynamic voltage restorer (DVR) to improve performance under various load conditions. The control scheme uses least error squares filters to estimate voltage magnitudes and phases, enabling accurate sag detection and compensation. It controls each phase independently using proportional-integral controllers in an outer loop and proportional controllers in an inner loop to damp filter resonances. Simulation results show the DVR can restore voltages within 5 milliseconds under both linear and non-linear loads for faults like single line-to-ground and line-to-line.
Analysis of Total Harmonic Distortion (THD) Level of Distribution Network Usi...IJERA Editor
The modern sensitive, Non-linear and sophisticated load affects the power quality. Dynamic Voltage Restorer (DVR) provides the fast, flexible and efficient solution to improve the power quality for such distribution network [8]. The active power, reactive power, variation of voltage, flicker, harmonics, and electrical behavior of switching operations are the major source of affecting power quality. The intent of this paper is to demonstrate the improvements obtained with DVR in power system network using MATLAB/SIMULINK. In this paper, an overview of the DVR, its functions, configurations, components, control strategies are reviewed. The Simulation results are presented to illustrate the performance of DVR in Total Harmonic Distortion (THD). The results showed clearly the performance of using DVR in improving THD level.
Voltage Sag and Swell Identification Using FFT Analysis and Mitigation with DVRIOSRJEEE
This document discusses the identification of voltage sags and swells in a power system network using FFT analysis and the mitigation of identified voltage issues using a dynamic voltage restorer (DVR). FFT analysis is used to identify voltage sags and swells existing in different phases of the power system. Simulation results in MATLAB/Simulink show the identification of sags and swells under various single-phase and multi-phase faults. The DVR is then able to mitigate the voltage sags and swells through injection of compensating voltages, as demonstrated through various simulation results showing stable load voltage. The paper presents a method to identify and mitigate common power quality issues like voltage sags and swells through the combined use of FFT
Iaetsd minimization of voltage sags and swells using dvrIaetsd Iaetsd
The document discusses the use of a Dynamic Voltage Restorer (DVR) to minimize voltage sags and swells in a distributed power system. A DVR is a custom power device that uses a voltage source inverter, injection transformer, and energy storage to inject voltage into the distribution system and regulate the load voltage during faults and disturbances. It functions by injecting a compensating series voltage to keep the load voltage at its pre-fault value. This maintains the quality of power supplied to sensitive loads and prevents equipment issues caused by voltage variations.
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.
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 Fuzzy Logic controller based Multifunctional Dynamic Voltage restorer in Di...IOSR Journals
This document describes a study that proposes using a fuzzy logic controller with a flux-charge model feedback algorithm to control a dynamic voltage restorer (DVR) in a distribution system. The DVR aims to improve transient response and eliminate steady-state error during voltage sags and other disturbances. Simulation results on a test system show the DVR can successfully compensate for a three-phase short circuit fault and voltage sag from starting a large induction motor, maintaining the load voltage at normal levels in less than half a cycle in both cases.
International Journal of Engineering Research and DevelopmentIJERD Editor
This document describes a Dynamic Voltage Restorer (DVR) using a fifteen level diode clamped multilevel inverter with multicarrier based pulse width modulation techniques. The DVR is used to mitigate voltage sags and improve power quality by injecting compensating voltage during disturbances. Simulations were conducted using MATLAB/Simulink comparing Phase Disposition PWM, Phase Opposition Disposition PWM, and Alternate Phase Opposition Disposition PWM techniques. The Alternate Phase Opposition Disposition PWM technique produced the lowest total harmonic distortion of 4.35%.
The International Journal of Engineering and Science (The IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
Modeling and simulation of dynamic voltage restorer for voltage sag mitigatio...IJRRR
Abstract- Power quality deals with utilization of electric energy from the distribution system successfully without interference or interruption. Various factors like interruption in power supply, under voltage, over voltage, unbalanced voltage or current, harmonic distortion, flickering voltage, voltage fluctuation voltage sag etc. result in poor power quality. These power quality related problems can be solved with the help of various custom power devices. Voltage sags are considered to be the most common type of disturbances in the field based on current power disturbances studies. Their impact on sensitive loads is rigorous. The impact ranges from load disruptions to financial losses. In spite of the technical advances in electronics, there are some pieces of equipment that are so sensitive that they are unable to withstand voltage sags. There are many varies methods to mitigate voltage sags, but a Custom Power Supply device is considered to be the most efficient method. This dissertation is the study of Dynamic Voltage Restorer (DVR) which is the most efficient and effective device to protect sensitive equipment against voltage sags. It has low cost, smaller size and it has dynamic response to the disturbance.
Keywords- Voltage sag, DVR, power system, mitigation
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.
Voltage dip mitigation in distribution system by using d statcomAlexander Decker
This document discusses using a D-STATCOM (Distribution Static Synchronous Compensator) to mitigate voltage dips in a distribution system. It begins by describing how voltage dips occur due to faults in the system and increase current. It then provides details on the structure and operation of a D-STATCOM, which contains a voltage source inverter, coupling transformer, and controller. The D-STATCOM can inject current into the system to regulate the voltage and compensate for sags, swells, and interruptions. Simulation results show that when a large load is applied, the D-STATCOM is able to mitigate the voltage dip and keep the bus voltages closer to their nominal values.
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1. International Journal of Engineering Inventions
ISSN: 2278-7461, www.ijeijournal.com
Volume 1, Issue 5 (September2012) PP: 47-55
Voltage Sag and Mitigation Using Algorithm for Dynamic
Voltage Restorer by PQR Transformation Theory
Prof. Shivanagouda B. Patil1, Dr. Shekhappa. G. Ankaliki2
1
E & E Engineering Department, Hirasugar Institute of Technology, Nidasoshi-591 236, Karnataka, India.
2
E & E Engineering Department, SDM College of Engineering & Technology, Dharwad-580 002, Karnataka,
India.
Abstract––Voltage sag is one of the power quality issue and Dynamic Voltage Restorer (DVR) is used for mitigation of
voltage sag. Voltage sag is sudden reduction in voltage from nominal value, occurs in a short time which can cause
damage and loss of production in industrial sector. In this paper, focus is given only on DVR using an algorithm and the
related implementations to control static series compensators (SSCs). Directly sensed three-phase voltages are
transformed to p-q-r co-ordinates without time delay. The controlled variables in p-q-r co-ordinates has better steady state
and dynamic performance and then inversely transformed to the original a-b-c co-ordinates without time delay,
generating control signals to SSCs. The control algorithm is used in DVR system. The simulated results are verified and
mitigation of sag is presented in this paper.
Key words––Voltage Sag, Static Series Compensator (SSCs), PQR Transformation, Dynamic Voltage Restorer (DVR)
I. INTRODUCTION
In many recent years, power quality disturbances become most issue which makes many researchers interested to
find the best solutions to solve it. There are various types of power quality disturbances in which voltage sag, voltage swell
and interruption. This paper introduces DVR and its operating principle for the sensitive loads. Simple control based SPWM
technique and „pqr‟ transformation theory [1] is used in algorithm to compensate voltage sags/swells. A scope of work is
DVR system will be simulated by using Matlab/Simulink tool box and results were presented. Due to the increasing of new
technology, a lot of devices had been created and developed for mitigation of voltage sag. Voltage sag is widely recognized
as one of the most important power quality disturbances [2]. Voltage sag is a short reduction in rms voltage from nominal
voltage, happened in a short duration, about 10ms to seconds. The IEC 61000-4-30 defines the voltage sag (dip) as a
temporary reduction of the voltage at a point of the electrical system below a threshold [3]. According to IEEE Standard
1159-1995, defines voltage sags as an rms variation with a magnitude between 10% and 90% of nominal voltage and
duration between 0.5cycles and one minute [4] & [5]. Voltage sag is happened at the adjacent feeder with unhealthy feeder.
This unhealthy feeder always caused by two factors which are short circuits due to faults in power system networks and
starting motor which draw very high lagging current. Both of these factors are the main factor creating voltage sag as power
quality problem in power system. Voltage sags are the most common power disturbance which certainly gives affecting
especially in industrial and large commercial customers such as the damage of the sensitivity equipments and loss of daily
productions and finances. An example of the sensitivity equipments are programmable logic controller (PLC), adjustable
speed drive (ASD) and chiller control. There are many ways in order to mitigate voltage sag problem. One of them is
minimizing short circuits caused by utility directly which can be done such as with avoid feeder or cable overloading by
correct configuration. The control of the compensation voltages in DVR based on dqo algorithm is discussed in [6]. DVR
is a power electronic controller that can protect sensitive loads from disturbances in supply system. Dynamic voltage
restorers (DVR) can provide the most commercial solution to mitigation voltage sag by injecting voltage as well as power
into the system. The mitigation capability of these devices is mainly influenced by the maximum load; power factor and
maximum voltage dip to be compensated [7]. In [12-17] Voltage Sag Mitigation Using Dynamic Voltage Restorer System
are discussed under fault condition and dynamic conditions.
II. DVR SYSTEM
Dynamic voltage restorer (DVR) is a series compensator which is able to protect a sensitive load from the
distortion in the supply side during fault or overloaded in power system. The basic principle of a series compensator is
simple, by inserting a voltage of required magnitude and frequency, the series compensator can restore the load side voltage
to the desired amplitude and waveform even when the source voltage is unbalanced or distorted [8]. This DVR device
employs gate turn off thyristor (GTO) solid state power electronic switches in a pulse width modulated (PWM) inverter
structure. The DVR can generate or absorb independently controllable real and reactive power at the load side. The DVR
also is made of a solid state dc to ac switching power converter that injects a set of three phase ac output voltages in series
and synchronism with the distribution feeder voltages [8]. The amplitude and phase angle of the injected voltages are
variable thereby allowing control of the real and reactive power exchange between the DVR and the distribution system [8].
The dc input terminal of a DVR is connected to an energy source or an energy storage device of appropriate capacity. The
reactive power exchange between the DVR and the distribution system is internally generated by the DVR without ac
47
2. Voltage Sag and Mitigation Using Algorithm for Dynamic Voltage Restorer…
passive reactive components. The real power exchanged at the DVR output ac terminals is provided by the DVR input dc
terminal by an external energy source or energy storage system. DVR structure comprises rectifier, inverter, filter and
coupling transformer shown in Fig.1. Besides, pulse width modulated (PWM) technique is using to control variable voltage.
Filter is using for elimination harmonic generated from high switching frequency in PWM technique. In power system
network, DVR system is connected in series with the distribution feeder that supplies a sensitive load shown in Fig. 2. There
are two main factors relating to the capability and performance of DVR working against voltage sags in a certain power
system: the sag severity level and the Total Harmonic Distortion (THD). Both of these in turn are mainly decided by the DC
source [9]
Fig. 1 DVR Structure
Fig. 2 DVR System in Power System
The Principle Operation of DVR System
In normal situation without short circuit in power system, a capacitor between rectifier and inverter (Fig. 1) will be
charging. When voltage sag happened, this capacitor will discharge to maintain load voltage supply. Nominal voltage will be
compared with voltage sag in order to get a difference voltage that will be injected by DVR system to maintain load voltage
supply. PWM technique is using to control this variable voltage. In order to maintain load voltage supply, reactive power
must be injected by DVR system. Practically, the capability of injection voltage by DVR system is 50% of nominal voltage.
It is sufficient for mitigation voltage sag because from statistic shown that many voltage sag cases in power system involving
less than 0.5 p.u. voltage drop.
Mathematical Model for Voltage Sag Calculation
In this principle the assumption is that the fault current is larger than the load current. The point of common
coupling is the point from which both fault and load are fed. Upon the occurrence of the fault which may be a line-line
ground fault, a short circuit current flow which leads to reduction in the voltage magnitude at the point of common coupling
(PCC) shown in Fig. 3. This voltage sag may be unbalanced and may be accompanied with a phase jump.
Fig. 3 Calculation for voltage sag
48
3. Voltage Sag and Mitigation Using Algorithm for Dynamic Voltage Restorer…
E
IF (1)
Zs ZF
Vsag I F Z F (2)
X X XF
tan 1 F tan 1 S (3)
RF RS RF
Where
Z S RS jX S , is the source impedance, Z F RF jX F , is the impedance between the PCC and the fault, and
E 1 p.u is the source voltage. The missing voltage which is the voltage difference between pre-sag condition and sagged
(faulted) condition which is given by equation (4) and vectorial representation is shown in Fig. 4.
Vmis sin g V presag Vsag (4)
Fig. 4 Vector Diagram Showing Voltage Sag
The missing voltage has to be provided by sag compensating device like Dynamic Voltage Restorer (DVR) which is injected
in series with the supply voltages to bring the voltages to pre-sag condition.
.
III. PROPOSED APPROACH
The objective of this paper is to implement DVR in series with a sensitive load. It is a series compensating device
which injects a set of controllable three-phase AC output voltages, in series and synchronism with the distribution feeder
voltages. The DVR employs solid state switching devices in a pulse width modulated inverter (PWMI), the magnitude and
phase angle of the injecting voltages can be controlled independently. In this work directly sensed three phase voltages are
transformed to p-q-r co-ordinates without time delay [1]. The controlled variables p-q-r co-ordinates have better steady state
and dynamic performance. Later these are inversely transformed to the original a-b-c co-ordinates without time delay. It
must able to respond quickly and experience no voltage sags to the end users of sensitive equipment shown in Fig. 3.
IV. BASIC CONTROL STRATEGIES OF DVR
The type of the control strategy mainly depends upon the type of the sensitive or critical load, i.e. it depends on the
sensitivity of the load to changes in magnitude, phase shift and wave shape of the voltage wave form. The control techniques
adopted should consider the limitations of the DVR like voltage injection capability and energy limit. Voltage sag
compensation can be done by DVR using real and reactive power transfer. Reactive power solely will not meet the
requirements of dynamic compensation of disturbances that require real power transfer.
The three basic control strategies are,
a) Pre-sag Compensation
b) In-phase Compensation
c) Energy Optimal Compensation
a) Pre-sag Compensation
In this technique, the DVR compensates for the difference between the sagged and the presag voltages by restoring
the instantaneous voltages to the same phase and magnitude as the nominal pre-sag voltages. In this method, in case there is
sag associated with phase shift, full phase compensation is provided so that the load is undisturbed as far as the phase angle
and magnitude are concerned. But there is no control of energy injected into the line and often exhausts the rating of the
DVR. The vector diagram for pre-sag compensation is shown in Fig. 5.
49
4. Voltage Sag and Mitigation Using Algorithm for Dynamic Voltage Restorer…
Fig. 5 Vector Diagram of Pre-sag Compensation
b) In-phase Compensation
In this method, the restored voltages are in-phase with the depressed source side voltages regardless of load current
and presag voltages, thus minimizing the magnitude of the injected voltage. Fig.4 shows phase compensation is not provided
but has got better performance in compensating a broader range of voltage sags. The vector diagram for inphase
compensation is shown in Fig. 6.
Fig. 6 Vector Diagram for Inphase Compensation
c) Energy Optimal Compensation
Voltages are injected at an angle that will minimize the use of real power since voltage restoration is the only
requirement. That means the DVR voltage is injected perpendicular to the load current but the current will change the phase
according to the new voltage applied to it and energy will be drawn from DVR. The vector diagram for optimal
compensation is shown in Fig.7.
Fig. 7 Vector Diagram for Optimal Compensation
V. COMPUTATION OF COMPENSATING VOLTAGES
There are many methods to calculate the compensating reference voltage waveforms for dynamic voltage restorers.
One of those methods is “PQR power theory”. An effective algorithm based on “PQR power theory” is used to calculate
reference compensating voltages. In this algorithm, the directly sensed three phase voltages are converted into p-q-r
coordinates instantaneously without any time delay. Then the reference voltages in p-q-r domain have simple forms - DC
50
5. Voltage Sag and Mitigation Using Algorithm for Dynamic Voltage Restorer…
values. The controller in p-q-r domain is very simple and clear, has better dynamic and steady state performance than
conventional controllers. The algorithm based on PQR power theory is used to get the reference compensation voltages in p-
q-r domain and transformed back to 0 domain to drive the space vector modulator to generate the firing signals for
inverter.
PQR Transformation Theory
The 3-phase voltages of three-phase a-b-c coordinates can be transformed to o coordinates as given below,
1 1 1
2 2 2 V
Vo a (5)
2 1 1 V
V 3
1
2
2 b
V Vc
0 3 3
2 2
If sinusoidal balanced voltagesvaREF , vbREF and vcREF are selected for the reference waves in the a-b-c coordinates,
the reference waves in o coordinates can be
calculated and shown below,
1 1
1 vaREF
v REF 2 2
vbREF
2 (6)
V REF
v REF 3 3
vcREF
3
0
2 2
v
Since the reference waves vaREF , bREF and vcREF are sinusoidal balanced, the 0-axis component voltage voREF
does not exist and the reference wave v REF v REF become sinusoidal and orthogonal on the plane.
Using the reference waves v REF v REF in the o coordinates in a mapping matrix, the voltages
ino coordinates can be transformed to p-q-r coordinates as given by (2).
v REF v REF
0
v REF v REF
vp vo
v REF v REF (7)
vq 0 v v
v REF v REF
r v
1 0 0
Where
v REF v REF 2 v REF 2 (8)
Combining (5) and (7) the voltages in a-b-c coordinates can be transformed to p-q-r coordinates as shown below,
Where C C1C2
1 1 1
2 2 2
Va (9)
C1
2
1
1
1 V
3 2 2 b
Vc
0 3 3
2 2
51
6. Voltage Sag and Mitigation Using Algorithm for Dynamic Voltage Restorer…
v REF v REF
0
v REF v REF
(10)
v v REF
C2 0 REF
v REF v REF
1 0 0
From p-q-r domain to a-b-c domain can be achieved by taking inverse of C,
va vp
C
1 (11)
vb vq
v v
c r
Where C 1 (C1C2 ) 1 C2 1C11
1
1 0
2 (12)
2 1 1 3
C11
3 2 2 2
1 1 3
2 2 2
0 0 1
v REF
v REF
C2 1 0 (13)
v REF v REF
v REF v REF
0
v REF v REF
PQR Transformation
Fig. 8 Physical Meaning of PQR Transformation
When three-phase voltages are sinusoidal and balanced, the locus of the sensed voltage space vector VSEN is a circle on the
plane. If the three-phase voltages are in-phase with the three-phase reference waves, the sensed voltage space
vector VSEN becomes aligned with the reference wave space vector VREF . In this case vq and vr do not exist while vp
comprises only a dc component that is equal to | VSEN |. This condition will be a target for the voltage sag compensation by a
DVR.
52
7. Voltage Sag and Mitigation Using Algorithm for Dynamic Voltage Restorer…
DVR Model Description
The block diagram of overall control flow is shown in Fig. 9. Here open loop feed forward control technique is
adopted. Upon the occurrence of sag, there is a reduction in the phase voltages on the downstream of the DVR. The data is
acquired by data acquisition system and detected. The speed with which the sag is detected depends upon the sensors and sag
detection algorithms. Then the three phase voltages are processed using PQR algorithm. The reference compensating
voltages are generated in PQR domain and transformed back to alpha-beta domain. The alpha and beta axis reference
voltages are given as inputs to drive the space vector modulator. The generated firing pulses are used to fire the switches of
the voltage Source Inverter (VSI). The topology of the VSI used is conventional 2-level, three-leg inverter and three-level
(multi-level configuration) diode clamped inverter. Depending upon the topology of the inverter, the number of firing pulses
may be 6/12.
Fig. 9 Simulation Model of Dynamic Voltage
VI. SIMULATION RESULTS
The simulation results carried out using Matlab/Simulink tool box for conventional two-level inverter using space
vector modulation scheme is presented.
The data used for simulation is,
Vsa = 230 0 ; Vsb = 230 -120 ; Vsc = 230 120 ; Vab= 350 V
The three phase output voltages generated by the VSI can be controlled both in magnitude and phase individually. Finally
the 3-phase voltages are filtered out by a low pass filter before injecting into the line via booster transformer. All the
simulations are carried out using MATLAB/SIMULINK tool box. The phase and line voltages in conventional two-level
inverter are shown in Fig.10. The sag compensation by DVR for double line to ground fault is shown in Fig.11. There is
voltage sag in phase „b‟ and phase „c‟. The DVR provides full magnitude and phase compensation instantaneously.
53
8. Voltage Sag and Mitigation Using Algorithm for Dynamic Voltage Restorer…
Fig. 10 Phase and Line Voltages in Conventional Two Level Inverter
Fig.11 Compensation of Sag by DVR for Phase b and c.
VII. CONCLUSION
In this paper, a complete simulated DVR system has been developed by using MATLAB/SIMULINK tool box.
The proposed scheme for DVR uses the PQR algorithm to generate the reference compensation voltages without time delay
applied to space vector modulator to drive the conventional two-level topology which generates the required compensation
voltages. It is shown that the simulated DVR developed, works successfully without lacks in its performance when applied to
a simulated power system network. By introducing DVR in the power network, it can help to improve power quality. It is
important to have a good delivery power quality in electrical power systems especially to the critical areas, such as in the
industrial sectors, in order to ensure the smoothness of the daily operations.
REFERENCES
1. Hyosung Kim, Frede Blaabjerg, Biritte Bak-Jensen, Jacho Choi, “Instantaneous Power Compensation in Three
Phase Systems by Using P-Q-R Theory” IEEE Journal 2001, PP 478-485.
54