A Soft-Switching Three-Phase DVR Equipped With a High-Frequency Isolated Converter

This paper proposes a soft-switching three-phase dynamic voltage restorer (THDVR) equipped with a high-frequency isolated converter. The proposed THDVR can keep the output voltage stable even under wide variations of voltage source. Besides, using simple resonant units, all main switches are turned on at zero-voltage-switching (ZVS). Also, all auxiliary switches are turned off at zero-current-switching (ZCS). The proposed topology can greatly reduce switching losses, and EMI. Moreover, replacing three low-frequency isolation transformers by a high-frequency isolated converter, the volume, weight and cost of the proposed THDVR can be reduced significantly. After all, some simulation results are presented to demonstrate the performance of the proposed soft-switching THDVR.