Performance Enhancement of DVR for Mitigating Voltage Sag/Swell using Vector Control Strategy

Abstract

This paper presents dynamic voltage restorer (DVR) with vector control strategy for mitigating power quality in power distribution systems. Whenever power quality problems, voltage sag/swell, occur DVR has to automatically detect and inject voltage components. The detection unit should be fast enough to know the variation of all phase voltages including magnitude and phase, to trigger the DVR to inject appropriate voltage components with required phase angles within very short period of time. Here, control strategy adopted for driving the DVR plays and important role in its performance. Any delay in the process or incorrect injection would be harmful to sensitive loads that are vulnerable to voltage sag/swell. This paper illustrates vector control strategy based on decoupling control to enhance performance of DVR during the process of compensation. It was found out that voltage sags/swells can be corrected faster with the proposed control strategy compared to conventional methods.