Controller Design of a New Universal Two-Phase SiC-GaN-Based DC-DC Converter for Plug-in Electric Vehicles

Abstract

Wide Band Gap (WBG) semiconductor technologies such as Silicon Carbide (SiC) and Gallium Nitride (GaN) are being replaced with Silicon (Si) MOSFETs and IGBTs in power switching converters. In hard-switching applications, GaN is more attractive because of its lower switching power losses. The DC-DC power module of the motor drive in Plug-In Electric Vehicles (PEVs) has a power rating range of 30–150 kW while the power rating of GaN is not that much high. A two-phase SiC-GaN-based converter can satisfy the demanded power, achieving the advantage of WBG technology, and avoid the complexity of multi-phase converter with high number of phases. Obtaining the maximum efficiency, the power sharing is not symmetrical. Therefore, a cascade controller is considered in this paper to control fully directional universal converter: drive/plug-in, boost/buck mode. The simulation results prove the satisfactory performance of the controller in all modes of operation.