Evaluation of SiC Devices for Over 500kHz Application Based on ZVS Buck Circuit

Abstract:
SiC devices are used in soft-switching topologies, where the switching frequency can be further increased, thus reducing the size of the passive devices, and increasing the power density of the product. Planar and trench gate are two main structures of SiC MOSFETs development technology. Despite the same technology, different manufacturers in the switching and thermal characteristics differ from each other, so it is necessary to compare and analyze the characteristics of different manufacturers of the devices to guide the engineers to make application selection. This paper is based on the design of a 600 kHz, 3.6 kW soft-switching ZVS Buck converter. First of all, the drive circuit for SiC devices high-frequency applications is optimized to improve its drive reliability. Moreover, the key parameters affecting the high-frequency applications of SiC devices are revealed by power loss breakdown. In addition, SiC devices from three manufacturers, with different structures and similar parameters, were selected for experimental comparison. The results verify the correctness of the analysis and provide a reference design for the high-frequency application of SiC devices.