Dynamic Voltage Restorer for Compensation of Voltage Sag: An Overview

Power quality is the major concern in today electrical power system. One of the major issues in improving power quality in distribution network. In distribution system voltage sag, voltage swell, harmonic interruption etc. are the main power quality problem. Among out of these, the voltage sag are most severe disturbances. To solve this problem, custom power devices are used. The DVR is a powerful device or a controller that is commonly used for voltage sags mitigation at the point of connection. DVR is fast, flexible and efficient solution to voltage sag problem. The DVR is a custom power device (CPD) which is connected in series with the network to maintain precise voltage in electrical distribution system. A DVR inject a voltage in series with the system voltage. This paper describes the principle of DVR operation, basic component, DVRs topologies system in distribution system, modeling and analysis of DVR. Fault are applied for DVR in distribution system and response of the system for this disturbances are observed. The result are achieved by using MATLAB.