Natural convection cooled SiC-based LLC Resonant Converters in wide voltage range battery charger application

Motive power battery charger needs to survive in a harsh industrial environment. A typical charger power converter module today utilizes direct forced air cooling, which introduces corrosive damages to the power converter components. This paper presents an innovative design for SiCbased LLC resonant converter with all natural convection cooling operating in wide voltage range application. In this design, there is no corrosive cooling air touching the power converter components. Therefore, the charger modules are much more durable. Both the phase shift full bridge control and the half and full bridge mode transition control are proposed to regulate the wide voltage range. The voltage gain of LLC resonant converter of both half bridge and full bridge is analyzed. The performance of the proposed topologies is verified through mathematical analysis, simulation and experimental results.