Switching loss reduction method for isolated DC to three-phase-Ac converter with an indirect matrix converter

This paper proposes a zero voltage switching (ZVS) method for a bidirectional isolated DC to three-phase AC converter with an indirect matrix converter. The phase shift control method is applied to a primary side converter and a secondary side converter to achieve ZVS and to generate a zero voltage period at the DC-link. A grid current is controlled by the three-phase converter with pulse density modulation based on delta-sigma modulation. From the experimental results, the proposed method reduces switching losses of the whole converter with the bidirectional operation. It is confirmed that the prototype circuit achieves a maximum efficiency of 95.0% with the discharge and charge mode. In addition, the grid current total harmonic distortion is lower than 5.0%. © 2020 The Institute of Electrical Engineers of Japan.