Interline Dynamic Voltage Restorer Research Articles

A superconducting magnetic energy storage based current-type interline dynamic voltage restorer for transient power quality enhancement of composited data center and renewable energy source power system

Simultaneous protection of sensitive renewable power generators and sensitive loads under transient voltage disturbances is an urgent issue in current power systems. Most existing solutions are based on separate custom power devices and energy storage systems. To efficiently utilize renewable energy under voltage sags and reduce energy storage capacity, a current-source-inverter interline dynamic voltage restorer (CSI-IDVR) based on superconducting magnetic energy storage (SMES) is proposed. The current source topology is designed for the IDVR to obtain a more appropriate current rise limitation and fewer switches. The CSI-based voltage dual control is designed and implemented to suppress the voltage oscillations, ensuring the transient stability of the sensitive renewable power generator and sensitive loads during asymmetric grid faults. An internet data center (IDC) combined with a typical renewable energy generator, i.e., doubly-fed induction generator (DFIG), is analyzed. Under transient voltage disturbances, the proposed CSI-IDVR can maintain the appropriate voltage profiles of the DFIG and IDC. Compared to the separate DVRs, the required SMES capacity in the CSI-IDVR can be substantially reduced. The feasibility and performance of the proposed CSI-IDVR are verified by numerical simulation.

WITHDRAWN: Optimized FOPID controller for power quality enhancement between feeders using interline dynamic voltage restorer

This paper proposes a novel control scheme for Interline dynamic voltage restorer (IDVR). The optimized fractional order PID (FOPID) controller is used in this work for power quality enhancement such as voltage regulation, harmonics distortion reduction, voltage sag and swells compensation, fault compensation etc. The gain parameters of FOPID controller are tuned by gravitational search algorithm (GSA). The performance of the suggested controller is evaluated by contrasting it with other optimization technique such as particle swarm optimization and cuckoo-search optimization algorithm. These simulation results represents that FOPID with GSA works better than the other techniques in terms of power quality enhancement.

MSRF Control Based Interline Dynamic Voltage Restoration in Distribution Line

This paper deals with the implementation of interline dynamic voltage restorer (IDVR) system using three-phase inverter integrated with PLL based MSRF controller for regulating the DC link voltage, and reducing the voltage sag. Voltage variation that frequently occurs either in the form of voltage sag or swells and it can cause major damage to the environment and distribution station. In this paper, interline dynamic voltage restorer has proposed which consist of more than one DVR's are commonly connected with the DC link capacitor of the system. Suitable control methods are developed for reduce the voltage sag in the line. Modified synchronous reference frame control has designed and implemented for both controls, and compensation of voltage sag. Conventional control method has some constraints such as high settling time of dc link voltage, and increase in harmonics that could be overcome by a new approach of MSRF based PLL has presented in this paper, which helps to compensate the voltage sag occurs in the system. Furthermore design and analysis of MSRF based IDVR is proposed to improve the efficiency, reducing the settling time of DC link voltage, reducing the harmonics distortion, and minimize the power quality issues by using MATLAB/SIMULINK.

A real time implementation of interline dynamic voltage restorer for improvement of power quality

Voltage deviations which occur frequently in the form of voltage sag/swell cause severe disturbances and damage sensitive loads present on the distribution side of power system. One of the feasible solutions to mitigate these voltage sags/swells is by utilising FACTS devices. The FACTS device proposed in this paper is interline dynamic voltage restorer (IDVR) which contains two or more dynamic voltage restorers (DVR) with a common DC link. In this paper, IDVR is designed for a specific application to mitigate power quality problems in an existing real time load. A case study of the load network data of BITS Pilani Hyderabad Campus in Telangana, India which is spread over 200 acres is considered as the real time load. Various multiple voltage sag/swell scenarios are analysed in the real time load. The results have proven that the IDVR can effectively mitigate multiple voltage sags/swells in the considered real time load.

A real time implementation of interline dynamic voltage restorer for improvement of power quality

Voltage deviations which occur frequently in the form of voltage sag/swell cause severe disturbances and damage sensitive loads present on the distribution side of power system. One of the feasible solutions to mitigate these voltage sags/swells is by utilising FACTS devices. The FACTS device proposed in this paper is interline dynamic voltage restorer (IDVR) which contains two or more dynamic voltage restorers (DVR) with a common DC link. In this paper, IDVR is designed for a specific application to mitigate power quality problems in an existing real time load. A case study of the load network data of BITS Pilani Hyderabad Campus in Telangana, India which is spread over 200 acres is considered as the real time load. Various multiple voltage sag/swell scenarios are analysed in the real time load. The results have proven that the IDVR can effectively mitigate multiple voltage sags/swells in the considered real time load.

Switched coupled inductor inverter-based interline dynamic voltage restorer with discrete wavelet transform-artificial neural network technique

An educational studies and understanding about theoretical and practical laboratory in power quality issues. Interline dynamic voltage restorer is used in the proposed system for mitigating voltage sag, swell, harmonics, and interruptions. The conventional topology of dynamic voltage restorer possessing voltage source inverter is modified into a switched coupled inductor inverter which has the clear edge in power transfer over the former one. The versatility of the controller is enhanced in this work by deploying an artificial neural network combined discrete wavelet transform. The artificial neural network and discrete wavelet transform aided pulse width modulation generation enhances the controller performance by mitigating the harmonics considerably. The simulation and experimental results reveal that interline dynamic voltage restorer renders solution for major power quality issues like voltage sag and swell. Interline dynamic voltage restorer-based SCII is implemented with field programmable gate array Spartan 6 controller and signal processing technique such as discrete wavelet transform that mitigates voltage sag and harmonics. Paper is constructed such that the students in Bachelor’s and Master’s program of Electrical engineering can understand the power quality, various issues, and mitigating the total harmonic distortion value. The equations related to real power transfer are derived which enable the students to clearly understand about the power exchange between the feeders. Further, it is applied in practical laboratory setup facility for understanding about power quality issues to students of both undergraduate and postgraduate courses.

An Interline Dynamic Voltage Restorer Using Neutral-Point-Clamped (NPC) Multilevel Converter

Because of increased number of sensitive loads and automated processes in industry, need for high quality power is nowadays inevitable. Deteriorated power quality my result in huge financial losses and also decreases the productivity. The power electronic based solutions for improving power quality have become more common in the recent years. One of these solutions is to use the Dynamic Voltage Restorer (DVR), which is a series-connected voltage compensator. Interline DVR (IDVR) is a special structure, in which two DVRs share a DC-link. These two DVRs are installed in two independent distribution feeders which may have two different voltage levels. In this paper, a new structure for IDVR is proposed. The proposed DVR is based on the multilevel converters. Therefore, we call it as Multilevel Converter based IDVR (MLC-IDVR). Because of using multilevel converter, the quality of voltage waveform in the proposed structure is improved in comparison with the conventional IDVR. Also, it is more suitable for higher voltage applications. The performance of the proposed MLC-IDVR is verified by simulation results carried out by PSCAD/EMTDC software.

Experimental Prototype Model of IDVR for Bidirectional Voltage Compensation

<span lang="EN-US">Interline Dynamic Voltage Restorer (IDVR) is an optimum solution to compensate voltage sag in multiple lines. The IDVR consisting of two or more DVRs connected to different feeders in a power system sharing a common DC link energy. This paper presents the hardware implementation of novel bidirectional voltage sag compensation by the IDVR in multiple feeders at same instance. A two line feeder power system with IDVR installed is considered. The IDVR is implemented using two VSI with filter. The control system of IDVR is developed using DSPACE 1103. </span>

A Novel Analysis of Improving Displacement Factor Using IVDFC in Distribution Systems

In this paper discuss the new approach for improving displacement factor using an Interline Dynamic Voltage Restoring and Displacement Factor Controlling Device (IVDFC) in a distribution system. An Interline Dynamic Voltage Restorer (IDVR) is perpetually engaged in distribution systems to mitigate voltage sag/swell problems. An IDVR simply consists of numerous dynamic voltage restorers (DVRs) sharing a common dc link connecting independent feeders to safe electric power to critical loads. The IDVR is operated that it hold the voltage across the critical load bus terminals constant at system nominal frequency irrespective of the changes occurring in source voltages frequency. While one of the DVRs compensates for the local voltage sag in its feeder, the other DVRs reload the common dc-link voltage. For normal voltage levels, the DVRs should be bypassed. Instead of bypassing the DVRs in normal conditions, this paper proposes operating the DVRs, if needed, to improve the displacement factor (DF) of one of the involved feeders. DF improvement can be achieved via active and reactive power exchange (PQ sharing) between different feeders. To successfully apply this concept, several constraints are addressed throughout the paper. The simulation model for this system is developed using MATLAB which is shown that the voltage across the critical load is regulated completely.

Voltage Sag Compensation in Fourteen Bus System during Line Interruption Using Interline Dynamic Voltage Restorer

<p>This paper deals with power quality improvement in fourteen bus system (FBS) using IDVR. Investigations were carried out to find the improvement of real and reactive power by employing IDVR during line outage condition. The closed loop responses of PI, PID and FL controlled systems are modelled and simulated using simulink and the results are obtained. Load flow studies were conducted for healthy system, FBS with line outage and FBS with line outage with inclusion of IDVR. The simulation studies indicate that, the voltage under line outage condition with IDVR is almost equal to the voltage under healthy condition. The Responses of closed loop systems with PI, PID and FLC are compared and the analysis shows the improvement in dynamic response in terms of settling time and steady state error. The advantages of proposed system is improved voltage stability, flexibility to control real and reactive powers and concluded that FLC based IDVR system had better time response. The prototype for four bus system with IDVR is modelled and the results are obtained.</p>

Improving the Performance of a Cascaded H-Bridge-Based Interline Dynamic Voltage Restorer

An interline dynamic voltage restorer (IDVR) is a new device for sag mitigation which is made of several dynamic voltage restorers (DVRs) with a common dc link, where each DVR is connected in series with a distribution feeder. During the sag period, active power can be transferred from a feeder to another one and voltage sags with long durations can be mitigated. IDVR compensation capacity, however, depends greatly on the load power factor, and a higher load power factor causes lower performance of IDVR. To overcome this limitation, a new idea is presented in this paper which enables reducing the load power factor under sag conditions and, therefore, the compensation capacity is increased. The proposed IDVR employs two cascaded H-bridge multilevel converters to inject ac voltage with lower total harmonic distortion and eliminates the necessity to low-frequency isolation transformers in one side. The validity of the proposed configuration is verified by simulations in the PSCAD/EMTDC environment. Then, experimental results on a scaled-down IDVR are presented to confirm the theoretical and simulation results.

A New Topology for Interline Dynamic Voltage Restorer Based on Direct Three-Phase Converter

In this paper, a new topology for Interline Dynamic Voltage Restorer (IDVR) is proposed. This topology contains two direct three-phase converters which have been connected together by a common fictitious dc-link. According to the kind of the disturbances, both of the converters can be employed as a rectifier or inverter. The converters receive the required compensation energy from the gird through the direct link which is provided by the dual-proposed switches. Due to the lack of the huge storage elements, the practical prototype of the proposed topology is more economical in comparison with the traditional structure. Moreover, compensating for long time duration is possible due to the unlimited eternal energy which is provided from the grids. The low volume, cost and weight are the additional features of the proposed topology in comparison with traditional types. This topology is capable to compensate both of the balanced and unbalanced disturbances. Furthermore, restoring the deep sags and power outages will be possible with the support from the other grid. Unlike the conventional topologies, the capability of compensation is independent from the power flow and the power factor of each grid. The performance of the proposed IDVR topology is validated by computer simulation with PSCAD/EMTDC software.

Performance Evaluation of Fuzzy Controller Based IPFC with IDVR

This study discusses the operating principles and control characteristics of a Interline Power Flow Controller (IPFC) and Interline Dynamic Voltage Restorer (IDVR) for power quality improvement. The power quality disturbance includes voltage sag, swell, notch, spike and transients etc. are normally occur in both transmission and distribution lines. Both the IPFC and IDVR connected power system performance is presented in a strategic approach. The fuzzy logic controller added in the system improves the system performance and isolate the system sag and swell. The MATLAB/Simulink based model developed for IPFC and IDVR. The output response of the system is presented and an remarkable conclusion proposed.

Enhanced High Performance Power Compensation Methodology by IPFC Using PIGBT-IDVR.

Currently, power systems are involuntarily controlled without high speed control and are frequently initiated, therefore resulting in a slow process when compared with static electronic devices. Among various power interruptions in power supply systems, voltage dips play a central role in causing disruption. The dynamic voltage restorer (DVR) is a process based on voltage control that compensates for line transients in the distributed system. To overcome these issues and to achieve a higher speed, a new methodology called the Parallel IGBT-Based Interline Dynamic Voltage Restorer (PIGBT-IDVR) method has been proposed, which mainly spotlights the dynamic processing of energy reloads in common dc-linked energy storage with less adaptive transition. The interline power flow controller (IPFC) scheme has been employed to manage the power transmission between the lines and the restorer method for controlling the reactive power in the individual lines. By employing the proposed methodology, the failure of a distributed system has been avoided and provides better performance than the existing methodologies.

An Interline Dynamic Voltage Restoring and Displacement Factor Controlling Device (IVDFC)

An interline dynamic voltage restorer (IDVR) is invariably employed in distribution systems to mitigate voltage sag/swell problems. An IDVR merely consists of several dynamic voltage restorers (DVRs) sharing a common dc link connecting independent feeders to secure electric power to critical loads. While one of the DVRs compensates for the local voltage sag in its feeder, the other DVRs replenish the common dc-link voltage. For normal voltage levels, the DVRs should be bypassed. Instead of bypassing the DVRs in normal conditions, this paper proposes operating the DVRs, if needed, to improve the displacement factor (DF) of one of the involved feeders. DF improvement can be achieved via active and reactive power exchange (PQ sharing) between different feeders. To successfully apply this concept, several constraints are addressed throughout the paper. Simulation and experimental results elucidate and substantiate the proposed concept.

Compensation range calculation in an interline dynamic voltage restorer (IDVR) encountering different voltage sag types

SUMMARY This paper is concerned with determining the compensation capability of an interline dynamic voltage restorer (IDVR) under various balanced and unbalanced voltage sag scenarios. An IDVR consists of two or more DVRs with a common dc link which enables active power exchange among DVRs. This feature increases the compensation range of an IDVR as compared with separate but otherwise similar DVRs with no energy storage. The steady-state modeling and analysis of an IDVR is briefly explained in this paper. The expressions governing power requirement for compensating various voltage sags are derived. Consequently, the constraints associated with an IDVR operation are obtained and an algorithm is developed to calculate the compensation range of an IDVR and two similar storage-less DVRs. Illustrative graphs demonstrate the operating characteristics of an IDVR and compare these characteristics with those of two similar storage-less DVRs. Copyright © 2013 John Wiley & Sons, Ltd.

Mitigation of voltage sag/swell using Dynamic voltage restorer (DVR)

The most noticeable topic for electrical engineering is power quality in recent year. Power quality problem is an occurrence manifested as a nonstandard voltage, current or frequency. Utility distribution networks, sensitive industrial load and critical commercial operation suffer from various types of outages and service interruption can cost significant financial losses. One of the major problems dealt here is the voltage sag. With the fast development in power electronics technology have made it possible to mitigate power quality problems. This work concentrates on the power quality problem such as voltage sag. Many of the devices such as STATCOM, tap changing transformer, UPFC and DVR are available to mitigate voltage sag problems. Among these, dynamic voltage restorer can provide the most commercial solution to mitigate voltage sag by injecting voltage as well as power in to the system. Dynamic Voltage Restorer is a series connected power electronics based device that can quickly mitigate the voltage sag in the system and restore the load voltage to the pre-fault value. This thesis first gives an introduction to relevant power quality problems for a DVR and power electronics controllers for voltage sag mitigation. Thereafter the operation and elements in DVR is described. In this thesis proposed utilizes the error signal to control the triggering of the switches of an inverter using Sinusoidal Pulse Width Modulation (SPWM) technique. Modeling and simulation of proposed DVR is implemented in MATLAB SIMULINK  Dynamic voltage restorer (DVR): It is a voltage source converter which is connected in series with supply through injection transformer where voltage sag or swell takes place. The DVR is most technically advanced and economical device for voltage sag mitigation in distribution system. Energy storage in DVR is responsible for supplying active power needed during voltage sag. If this energy is obtained from neighbour feeder than it is called interline dynamic voltage restorer.

Voltage Quality Improvement with Neural Network-Based Interline Dynamic Voltage Restorer

Custom power devices such as dynamic voltage restorer (DVR) and DSTATCOM are used to improve the power quality in distribution systems. These devices require real power to compensate the deep voltage sag during sufficient time. An interline DVR (IDVR) consists of several DVRs in different feeders. In this paper, a neural network is proposed to control the IDVR performance to achieve optimal mitigation of voltage sags, swell, and unbalance, as well as improvement of dynamic performance. Three multilayer perceptron neural networks are used to identify and regulate the dynamics of the voltage on sensitive load. A backpropagation algorithm trains this type of network. The proposed controller provides optimal mitigation of voltage dynamic. Simulation is carried out by MATLAB/Simulink, demonstrating that the proposed controller has fast response with lower total harmonic distortion.

Implementation and Performance Evaluation of a Fast Dynamic Control Scheme for Capacitor-Supported Interline DVR

The implementation of a fast dynamic control scheme for capacitor-supported interline dynamic voltage restorer (DVR) is presented in this paper. The power stage of the DVR consists of three inverters sharing the same dc link via a capacitor bank. Each inverter has an individual inner control loop for generating the gate signals for the switches. The inner loop is formed by a boundary controller with second-order switching surface, which can make the load voltage ideally revert to the steady state in two switching actions after supply voltage sags, and also gives output of low harmonic distortion. The load-voltage phase reference is common to all three inner loops and is generated by an outer control loop for regulating the dc-link capacitor voltage. Such structure can make the unsagged phase(s) and the dc-link capacitor to restore the sagged phase(s). Based on the steady-state and small-signal characteristics of the control loops, a set of design procedures will be provided. A 1.5-kVA, 220-V, 50-Hz prototype has been built and tested. The dynamic behaviors of the prototype under different sagged and swelled conditions and depths will be investigated. The quality of the load voltage under unbalanced and distorted phase voltages, and nonlinear inductive loads will be studied.

A Novel Technique to Compensate Voltage Sags in Multiline Distribution System—The Interline Dynamic Voltage Restorer

The dynamic voltage restorer (DVR) provides a technically advanced and economical solution to voltage-sag problem. As the voltage-restoration process involves real-power injection into the distribution system, the capability of a particular DVR topology, especially for compensating long-duration voltage sags, depends on the energy storage capacity of the DVR. The interline DVR (IDVR) proposed in this paper provides a way to replenish dc-link energy storage dynamically. The IDVR consists of several DVRs connected to different distribution feeders in the power system. The DVRs in the IDVR system share a common energy storage. When one of the DVR compensates for voltage sag appearing in that feeder, the other DVRs replenish the energy in the common dc-link dynamically. Thus, one DVR in the IDVR system works in voltage-sag compensation mode while the other DVRs in the IDVR system operate in power-flow control mode. In principle, IDVR can operate effectively when constituent DVRs are electrically (not necessarily physically) far apart. Closed-loop load voltage and current-mode-control techniques are used as the control strategy in the two modes of operation. Experimental results obtained for a laboratory prototype of the IDVR are presented to show the effectiveness and the efficacy of the proposed IDVR system to improve power quality