An LLC Converter for Power Switch Evaluation in Resonant Topology and back-to-back Loading Method

Abstract:
This paper presents a SiC MOSFET-based DC-DC converter design for evaluating power switches in a resonant circuit, common for EV charging applications. The LLC resonant circuit was developed using the first harmonic approximation method. The control was implemented by introducing a hardware-in-the-loop (HIL) setup. The back-to-back loading method reduces laboratory equipment constraints and lowers the power dissipation. A modular approach was incorporated in the system design with the capability to deliver a maximum power of 20 kW with up to three MOSFETs in parallel. Simulation and measurements were conducted for two different SiC MOSFET generations and the results were compared.