Soft-Switched SiC Based DC-DC Converter with Low-Loss Modulation in DC-AC Inverter for Highly Efficient EV/HEV Powertrains

This paper introduces a Silicon Carbide (SiC) based powertrain for Electric/Hybrid Electric Vehicles (EV/HEV) featuring a cascaded topology. The design comprises a DC-DC stage with a three-phase interleaved boost converter (IBC) employing SiC MOSFETs switching at 250 kHz, followed by a DC-ACstage utilizing a three-phase inverter. The integration of soft switching in the DC-DC stage and the implementation of a low-loss PWM method i.e., 240°-Clamped Pulse Width Modulation (240CPWM) in the DC-AC stage aim to significantly enhance powertrain's efficiency. Thermal modeling and simulation results at 10 kW validate the efficacy of the proposed topology in achieving high efficiency in EV/HEV powertrains. The combined efficiency of DC-DC stage and DC-AC stage with the proposed topology is as high as 98% as opposed to 95% in conventional topology at 10 kW.