A novel modulation strategy for active rectification of a snubber less soft-switched single stage 30 high frequency link DC-AC converter

Abstract

This paper proposes a novel modulation strategy for active rectification of a single stage, isolated, three-phase high frequency link DC-AC converter. The proposed modulation strategy results in zero voltage switching (ZVS) of the DC side converter and zero current switching (ZCS) of AC side converter at all operating conditions without using additional snubber circuit. The technique also ensures magnetic flux balance of transformer within a switching cycle. High frequency transformer (HFT) flux balance results in significant reduction in size and weight and hence improves power density. The paper presents a detailed description of the proposed modulation strategy for unity power factor (UPF) operation. Important simulation results are shown to verify the converter operation.