Implementation of an Isolated Phase-Modular-Designed Three-Phase PFC Rectifier Based on Single-Stage LLC Converter

This paper proposes a new phase-modular three-phase single-stage rectifier based on the LLC resonant converter. The proposed rectifier provides power factor correction, output voltage regulation, and electrical isolation in a single-stage modular-designed approach. The proposed rectifier has minimal switching loss due to the ZVS and ZCS operations of all the switches and diodes. Moreover, the proposed AC-DC converter does not use any bulky passive components and hence is suitable for high power density applications that also require high power conversion efficiency. Design notes and specifications of a single module are provided in this paper. Computer simulation results verified the unity PFC performance and output voltage regulation using a small output capacitance without any low-frequency ripple. Furthermore, the feasibility of the proposed rectifier is validated by the experimental results of a digitally implemented GaN-based laboratory prototype.