13kW Motor Drive with Top-Side Cooled SiC MOSFETs for HVAC E-Compressor in EVs

This paper presents the design of a 13 kW top-side cooled (TSC) SiC MOSFET-based motor drive for the E-compressor in a heating, ventilation and air-conditioning (HVAC) system in Electric Vehicles (EVs), which demonstrates high efficiency, high frequency operation, and high power density. To achieve better thermal performance and facilitate automated production, an assembly method and thermal design for top-side cooled SiC MOSFETs is detailed in this work. A digital-controlled motor drive prototype with 1200 V / 75 mΩ SiC MOSFETs switched at 20 kHz was built to drive a Permanent Magnet Synchronous Motor (PMSM), showing a peak efficiency of over 98.5% thanks to the low power loss and superior thermal performance of the SiC MOSFETs. Compared with traditional Silicon IGBT-based solution, the proposed design has 60% lower power loss at light load (< 3 kW) and up to 54°C cooler at full load, enabling higher efficiency and optimized battery utilization across all load conditions.