SiC MOSFETs - the Inevitable Trend for 800V Electric Vehicle Air Conditioning Compressors

Unlike traditional fuel vehicles, the air conditioning system of electric vehicles not only undertakes the thermal management of the cabin but also the thermal management of the battery system and even the thermal management of the electric motor control. The high demand for heating and cooling power leads to a significant reduction in cruising range. As the heart of the air conditioning system, E-compressors play the most critical role in the thermal management of electric vehicles. This paper shows that SiC MOSFETs are preferred for 800V electric vehicle E-compressors compared to Si IGBTs. A systematic comparison of SiC MOSFET and conventional IGBT solutions for E-compressor application in terms of system energy efficiency, compressor operation boundary, NVH performance, and system miniaturization trend is described in this paper. Besides, the cost reduction potential and gate oxide reliability issues of SiC MOSFET are also discussed.