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Review of Dynamic Voltage Restorer (DVR) Based Controlling Approaches for Grid Networks

Power quality is essential in the most advanced and high-end machinery, whose performance depends on the power supply's quality. The power quality issues like voltage sag, swell, interruptions, noises, and harmonics are occurred due to fluctuations in voltage/current or frequency or phase variations resulting from machinery failures. To improve power quality, customized power devices are recommended in most industries. A Dynamic voltage restorer (DVR) is recommended as a cost-effective solution to enhance the power quality. The DVR provides power-electronics solutions to mitigate and compensate for voltage sag/swell issues. This manuscript discusses the comprehensive review of the DVR-based principle operations, topologies, and control methods. The study examines the power-quality issues, DVR principle concerning the modes of operations, and DVR topologies in the presence or absence of an energy storage Unit (ESU). The detailed discussion of the DVR-based controlling approaches to mitigate the voltage sag/swell/faults are studied and summarized with tabulation. The performance comparison of the % THD for load voltages using DVR based on different controlling approaches at sag and swell conditions is highlighted.