scholarly journals A Modified Series Voltage Controller for Power Conditioning

2019 ◽  
Vol 8 (4) ◽  
pp. 10164-10170
Keyword(s):  
Power Quality ◽  
Supply Voltage ◽  
Harmonic Distortion ◽  
Cost Effective ◽  
Voltage Regulator ◽  
Dynamic Voltage Restorer ◽  
Voltage Controller ◽  
Power Conditioner ◽  
Quality Issues ◽  
Park Transformation

A compensation method for mitigation of voltage related power quality problems with the use of Series Voltage Regulator well known as Series Active Power Filter or Dynamic Voltage Restorer is presented in this paper. The classical control algorithm used for series voltage regulator based on the Park transformation is modified by introducing a Selective Harmonic Filter at detection stage of source current in order to compensate harmonic frequencies which mainly affect power frequency voltages. The significant outcomes are sag restoration, reduction of total harmonic distortion and removal of transients from the supply voltage. Thus it makes possible to improve performance of series voltage controller as power conditioner to mitigate various voltage related power quality issues. The proposed approach is cost effective because same series voltage controller can be used as power conditioner by modifying control strategy used. Also it is possible to eliminate use of PI controller from control circuitry. The usefulness and robustness of the proposed mitigation strategy is confirmed by simulation studies. The presented series voltage controller has ability to mitigate the power quality issues arising due to charging of electric vehicles.

scholarly journals Simulation-based Analysis of a Dynamic Voltage Restorer under Different Voltage Sags with the Utilization of a PI Controller

2020 ◽  
Vol 10 (4) ◽  
pp. 5889-5895
Author(s):  
A. H. Soomro ◽  
A. S. Larik ◽  
M. A. Mahar ◽  
A. A. Sahito ◽  
I. A. Sohu
Keyword(s):  
Power Quality ◽  
Harmonic Distortion ◽  
Cost Effective ◽  
Pi Controller ◽  
Voltage Control Strategy ◽  
Constant Frequency ◽  
Dynamic Voltage Restorer ◽  
Matlab Simulink ◽  
Voltage Restorer ◽  
Dynamic Voltage

Power quality problems are becoming a major issue. Every utility company consumer desires to receive steady-state voltage, i.e. a sinusoidal waveform of constant frequency as generated at power stations, but the influence of disturbances in the shape of sags and swells, interruptions, transients and harmonic distortions which affect power quality, resulting in loss of data, damaged equipment, and augmented cost. The most powerful voltage disturbance is the sag voltage. In this paper, a Dynamic Voltage Restorer (DVR) is proposed for sag voltage compensation. It is cost-effective and protects critical loads in a good manner from balanced or unbalanced sag voltage. Control strategy (such as a PI controller) is adopted with DVR topology and the performance of such a device with the proposed controller is analyzed through simulation in MATLAB/Simulink. Three types of faults are utilized, which are available in MATLAB/Simulink pack, for obtaining the sag voltage. The specific range of total harmonic distortion percentage is also discussed. After the result validation of the DVR topology in MATLAB/Simulink, it has been seen that the proposed topology is able to compensate the sag voltage of any type of fault and reduce the unbalancing and voltage distortions of the grid.

scholarly journals Linearly Decoupled Control of a Dynamic Voltage Restorer without Energy Storage

Mathematics ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1794
Author(s):  
Luis Ramon Merchan-Villalba ◽  
Jose Merced Lozano-Garcia ◽  
Juan Gabriel Avina-Cervantes ◽  
Hector Javier Estrada-Garcia ◽  
Alejandro Pizano-Martinez ◽  
...  
Keyword(s):  
Power Quality ◽  
Control Strategy ◽  
Supply Voltage ◽  
Matrix Converter ◽  
Operating Conditions ◽  
System Stability ◽  
Linear Control ◽  
Dynamic Voltage Restorer ◽  
Voltage Restorer ◽  
Dynamic Voltage

This paper presents the design of a decoupled linear control strategy for a Dynamic Voltage Restorer (DVR) that utilizes a Matrix Converter (MC) as its core element and obtains the compensation energy directly from the power system. This DVR is intended to cope with power quality problems present in supply system voltages such as balanced and unbalanced variations (sags and swells), and harmonic distortion. The dynamic model of the complete system that includes the Matrix Converter, the input filters and the electrical grid, is performed in the synchronous reference frame (dq0), to have constant signals at the fundamental frequency, in order to design the proposed linear control strategy. The coupling in the dq components of the system output signals caused by the Park Transformation, is eliminated by a change of variable proposed for the controller design, giving rise to a decoupled linear control. In this way, the strategy developed makes it possible to establish an adequate transient response for the converter in terms of convergence speed and overshoot magnitude, in addition to ensuring closed-loop system stability under bounded operating conditions. Unlike other proposals that utilize complex modulation strategies to control the MC under adverse conditions at the input terminals, in this case, the ability to generate fully controllable output voltages, regardless of the condition of the input signals, is provided by the designed linear controller. This allows the development of a multifunctional compensator with a simple control that could be of easy implementation. In order to verify the performance of the control strategy developed, and the effectiveness of the proposed DVR to mitigate the power quality problems already mentioned, several case studies are presented. The operational capacity of the MC is demonstrated by the obtained simulation results, which clearly reveals the capability of the DVR to eliminate voltage swells up to 50% and sags less than 50%. The compensation limit reached for sags is 37%. In relation to compensation for unbalanced voltage variations, the DVR manages to reduce the voltage imbalance from 11.11% to 0.37%. Finally, with regard to the operation of the DVR as an active voltage filter, the compensator is capable of reducing a THD of 20% calculated on the supply voltage, to a value of 1.53% measured at the load terminals. In the last two cases, the DVR mitigates disturbances to a level below the criteria established in the IEEE standard for power quality. Results obtained from numerical simulations performed in MATLAB/Simulink serve to validate the proposal, given that for each condition analyzed, the MC had succesfully generated the adequate compensation voltages, thus corroborating the robustness and effectiveness of the control strategy developed in this proposal.

A Matrix Converter for Compensating Unbalanced and Harmonic Input Voltages

2012 ◽  
Vol 13 (1) ◽  
Author(s):  
Jose M. Lozano ◽  
Juan M. Ramirez
Keyword(s):  
Power Quality ◽  
Distribution Systems ◽  
Harmonic Distortion ◽  
Matrix Converter ◽  
Space Vector Modulation ◽  
Dynamic Voltage Restorer ◽  
Voltage Restorer ◽  
Svm Algorithm ◽  
Dynamic Voltage ◽  
Vector Modulation

A dynamic voltage restorer (DVR) based on an AC-AC converter is presented. It is able to compensate different common disturbances in distribution systems, with the purpose of improving the power quality delivered to the users. A prototype has been assembled to test the feasibility of the proposition. In this paper a modulation strategy based on the well known space vector modulation (SVM) algorithm is presented in order to synthesize controllable voltages in magnitude and waveform for compensation purposes. Unbalanced and harmonic distortion conditions in the supply voltages are taken into account. These results positively confirm the design, simulation, assembling, and expectations about the device.

scholarly journals Improvement of Power Quality using DVR by Different Control Techniques

2019 ◽  
Vol 8 (3) ◽  
pp. 7366-7369
Keyword(s):  
Power Systems ◽  
Power Quality ◽  
Power Distribution ◽  
Distribution Systems ◽  
Fuzzy Logic Controller ◽  
Electrical Power ◽  
Harmonic Distortion ◽  
Dynamic Voltage Restorer ◽  
Efficient Operation ◽  
Dynamic Voltage

Power quality has been an issue in electrical power systems. Disturbances occur in power quality which effects machines, some electric devices and severe cause will get very serious damages. For normal and efficient operation it’s necessary to compensate and acknowledge every type of the disturbances at earlier time of the power system. Many sorts of Custom Power Devices (CPD’s) are used to resolve these issues .Here at present, one in every of those devices, Dynamic Voltage restorer (DVR) is conferred. In power distribution systems this is often best and effective device employed. During this project new structure and control methodology of multifunctional DVRs for voltage quality correction are mentioned. Proportional Integral Controller and Fuzzy Logic Controller are used for the PQ improvement. The performance of the device and Total Harmonic Distortion is compared with each other. The performance of the device like voltage swell, sag is projected.

scholarly journals Voltage Sag, Voltage Swell and Harmonics Reduction Using Unified Power Quality Conditioner (UPQC) Under Nonlinear Loads

2021 ◽  
Vol 17 (2) ◽  
pp. 140-150
Author(s):  
Ahmed Qasim ◽  
Fadhil Tahir ◽  
Ahmed Alsammak
Keyword(s):  
Power Quality ◽  
Power Distribution ◽  
Reactive Power ◽  
Supply Voltage ◽  
Harmonic Distortion ◽  
Distribution Networks ◽  
Unit Vector ◽  
Voltage Sag ◽  
Nonlinear Loads ◽  
Voltage Swell

In light of the widespread usage of power electronics devices, power quality (PQ) has become an increasingly essential factor. Due to nonlinear characteristics, the power electronic devices produce harmonics and consume lag current from the utility. The UPQC is a device that compensates for harmonics and reactive power while also reducing problems related to voltage and current. In this work, a three-phase, three-wire UPQC is suggested to reduce voltage-sag, voltage-swell, voltage and current harmonics. The UPQC is composed of shunt and series Active Power Filters (APFs) that are controlled utilizing the Unit Vector Template Generation (UVTG) technique. Under nonlinear loads, the suggested UPQC system can be improved PQ at the point of common coupling (PCC) in power distribution networks. The simulation results show that UPQC reduces the effect of supply voltage changes and harmonic currents on the power line under nonlinear loads, where the Total Harmonic Distortion (THD) of load voltages and source currents obtained are less than 5%, according to the IEEE-519 standard.

scholarly journals Dynamic Voltage Restorer (DVR): A Comprehensive Review of Topologies, Power Converters, Control Methods, and Modified Configurations

Energies ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 4152
Author(s):  
Ali Moghassemi ◽  
Sanjeevikumar Padmanaban
Keyword(s):  
Power Quality ◽  
Power Converters ◽  
Economic Losses ◽  
Voltage Sags ◽  
Control Methods ◽  
Dynamic Voltage Restorer ◽  
Comprehensive Review ◽  
Voltage Restorer ◽  
Dynamic Voltage ◽  
Quality Issues

Power quality is a pressing concern and of the utmost importance for advanced and high-tech equipment in particular, whose performance relies heavily on the supply’s quality. Power quality issues like voltage sags/swells, harmonics, interruptions, etc. are defined as any deviations in current, voltage, or frequency that result in end-use equipment damage or failure. Sensitive loads like medical equipment in hospitals and health clinics, schools, prisons, etc. malfunction for the outages and interruptions, thereby causing substantial economic losses. For enhancing power quality, custom power devices (CPDs) are recommended, among which the Dynamic Voltage Restorer (DVR) is considered as the best and cost-effective solution. DVR is a power electronic-based solution to mitigate and compensate voltage sags. This paper provides a thorough discussion and comprehensive review of DVR topologies based on operations, power converters, control methods, and applications. The review compares the state-of-the-art in works of literature, and comparative study on power quality issues, the DVR principle along with its operation modes, the DVR components, the DVR topologies based on energy storage, the DVR topologies based on single-/three-phase power converters, and the DVR topologies based on control units that have different control processing stages. Furthermore, modified and improved configurations of the DVR, as well as its integration with distributed generations, are described. This work serves as a comprehensive and useful reference for those who have an interest in researching DVRs.

scholarly journals Implementation of NN controlled DVR for Enhancing The Power Quality By Mitigating Harmonics

2018 ◽  
Vol 9 (2) ◽  
pp. 738 ◽  
Author(s):  
Abirami Periaswamy ◽  
Merin Lizbeth George
Keyword(s):  
Power Systems ◽  
Power Quality ◽  
Distribution Systems ◽  
Cost Effective ◽  
Vital Role ◽  
Dynamic Voltage Restorer ◽  
Neural Network Controller ◽  
Marquardt Algorithm ◽  
Power Switches ◽  
Dynamic Voltage

<p>Now a days there is a widespread use of  semiconductor devices, which are mostly implemented as the power switches for converters and inverters. These converters and inverters play a vital role in power systems both in transmission and distribution systems. This provides a way for the introduction of harmonics in the power system which leads to poor power quality. To overcome this many solutions have been suggested by the research community but each solution holds its own merits and demerits. Of all these suggested solutions, the Dynamic Voltage Restorer is one of the most cost effective systems for various power quality issues. In this paper the DVR is considered for enhancing the power quality by reducing the harmonics generated because of sensitive loads. Here the power quality is enhanced by controlling the DVR using Neural Network Controller which is trained by Levenberg Marquardt algorithm. In this paper the THD analysis of the voltage quantity is analysed by introducing an unbalanced three phase fault in the system. The simulation is done by using MATLAB/Simulink. From the results, it is verified that the harmonics are reduced by the NN controlled DVR unit. Also the simulation results are verified with the hardware results. </p>

scholarly journals Reparation of voltage disturbance using PR controller-based DVR in Modern power systems

2021 ◽  
Vol 27 (1) ◽  
pp. 16-29
Author(s):  
D. Danalakshmi ◽  
S. Prathiba ◽  
M. Ettappan ◽  
D. Mohan Krishna
Keyword(s):  
Smart Grid ◽  
Power Systems ◽  
Power Quality ◽  
Distribution System ◽  
Harmonic Distortion ◽  
Fast Response ◽  
Grid Environment ◽  
Dynamic Voltage Restorer ◽  
Pr Controller ◽  
Compensating Devices

Abstract The Smart Grid environment gives more benefits for the consumers, whereas the power quality is one of the challenging factors in the smart grid environment. To protect the system equipment and increase the reliability, different filter technologies are used. Even though, consumers’ expectations towards the power quality are not fulfilled. To overcome these drawbacks and enhance the system reliability, a new Custom Power Devices (CPD) are introduced in the system. Among different CPDs, the Dynamic Voltage Restorer (DVR) is one of the voltage compensating devices that is used to improve the power quality during distortions. When the distortions such as voltage swell and sag occur in the distribution system, the control strategy in the DVR plays a significant role. In this article, the DVR performance using Proportional Integral (PI), Proportional Resonant (PR) controllers are analyzed. A robust optimization algorithm called Self Balanced Differential Evolution (SBDE) is used to find the optimal gain values of the controllers in order to reach the target of global minimum error and obtain fast response. Then, a comparative analysis is performed between different controllers and verified that the performance of PR controller is superior than the other controllers. It has been found that the proposed PR controller strategy reduces the Total Harmonic Distortion (THD) values for all types of faults. The proposed SBDE optimized DVR with PR controller reduces the THD value less than 4% under voltage distoration condition. The DVR topology is validated in MATLAB/SIMULINK in order to detect the disturbance and inject the voltage to compensate the load voltage.

SOFC-Supported Hybrid PSOGSA-Optimized Dynamic Voltage Restorer for Power Quality Enhancement

2021 ◽  
pp. 2250006
Author(s):  
P. Sathish Babu ◽  
C. K. Sundarabalan ◽  
C. Balasundar
Keyword(s):  
Power Quality ◽  
Control Method ◽  
Supply Voltage ◽  
Test System ◽  
Pi Controller ◽  
Optimal Method ◽  
Dynamic Voltage Restorer ◽  
Voltage Restorer ◽  
Dynamic Voltage ◽  
Tuning Methods

A novel optimal method of a Dynamic Voltage Restorer (DVR) supported by solid oxide fuel cell (SOFC) and its simplified topological structure are proposed. DVR is a power-electronic converter-based device, and the objective of the DVR control system is to minimize supply voltage variations at the load terminals. This is attained by generating a compensating voltage at the series injection transformer. Conventional controllers are mathematical model-based; also, the particular system varies widely, and nonlinear factors make the PI controller tuning more challenging to some extent. As a result, an intelligent PI optimization control method is essential. This paper proposes Hybrid PSOGSA to search for optimal values of two PI control parameters for the [Formula: see text]–[Formula: see text]-axis components by considering a novel bi-objective function. The performance of the test system is analyzed for five test scenarios using the proposed PI controller with SPSO-optimized and Ziegler–Nichols tuning methods. DVR system provides an excellent control performance in the transient and steady states for compensating the sensitive load voltages with almost zero steady-state errors. Simulation results show that the proposed approach can provide improved performance than PSO-optimized and classical PI controllers for the power quality indices measured.

Sign in / Sign up

Export Citation Format

Share Document