Design of GaN based 72V,3.3KW LLC Resonant Converter for on-board EV Charger

This paper proposes the designing procedure for Inductor-Inductor-Capacitor (LLC) Resonant DC-DC Converter using GaN HeMT MOSFET for on-board battery charger used in Electric Vehicle application. Based on LLC Converter's features and characteristics, design specification is studied. By using Fundamental Harmonics Approximation model, Zero Voltage Switching (ZVS) on the primary side has been reported by operating in different operating regions. The control scheme for the proposed converter is discussed to regulated output voltage. Finally, the model is proposed and tested using MATLAB simulation to transform 400 V input voltage to an output voltage range of 64.8-86.4 V at 3.3 KW, taking all parameters into account step by step.