Si/WBG Hybrid Half-Bridge Converter Using Coupled Inductors for Power Quality Improvement and Control Simplification

The Si/WBG hybrid half-bridge (HHB) converter with hybrid frequency interleaved operation (HFIO) aims to offer an improved cost-performance tradeoff but suffers from uncompensable and low-frequency fluctuations in power quality issues and complicated control design. In this article, an Si/wide-bandgap (WBG) coupled half-bridge (CHB) is proposed, which coordinates the hybrid-frequency interleaved Si and WBG phase operation by a coupled inductor. By optimal configuring the coupling coefficient, the un-compensable, and low-frequency fluctuations of power quality issues can be completely addressed. Meanwhile, the HFIO controller is redesigned from the perspective of the modulated model predictive control, and the implementation can be greatly simplified under the selected optimal coefficient. A 3.3 kW Si insulated gate bipolar transistor (IGBT)/SiC
mosfet
CHB totem-pole bridgeless PFC (TPBPFC) prototype is built as a case study to validate the proposed design concept. In comparison to conventional Si/SiC HHB TPBPFC, the proposed Si/SiC CHB TPBPFC can achieve a maximum 64.7% total harmonic distortion (THD) reduction, demonstrating the same low ripple and THD performance as full high-frequency two-phase all-SiC design in all operating ranges while with 16.7% cost reduction.