A PWM SRT DC/DC Converter for 6.6-kW EV Onboard Charger

This paper suggests another candidate for a dc/dc converter in an electric vehicle onboard charger. Maintaining topological characteristics similar to those of conventional resonant converters, it is operated with a constant frequency PWM for charging control. Since the converter uses a secondary resonant tank, soft-switching and resonant operations can be separated. A practical design procedure is suggested to guarantee the normal operation, and the feasibility of the PWM SRT converter is verified with a 6.6-kW prototype charger designed by the procedure.