Low Temperature Evaluation of Silicon Carbide (SiC) based Converter

Cryogenic power electronics is regarded as the next step to improve converter efficiency and power density. Thus, investigations on component and converter performances under low temperature operations are of great importance. Silicon carbide (SiC) devices have gradually replaced traditional Silicon (Si) devices in high voltage and high power applications. This is due to their fast switching speed and low switching loss. In this article, the feasibility and performance of SiC devices based power converters are investigated under low temperature operation. Firstly, the individual components performances are evaluated under low temperatures, including SiC MOSFET, gate driver, capacitor, magnetic components, and SiC Schottky diode. Then, a 600 W resonant converter based DC transformer was built and tested under low temperatures. The efficiency for the converter with ferrite cores drops from 97.86% at room temperature (298 K) to 93.44% at 143 K. Different magnetic components are tested and comparisons are made.