Thermal Simulation for Power Density Optimization of SiC-MOSFET Automotive Inverter

In the paper thermal optimizations for a 1200V, 150A, three-phase SiC-MOSFET automotive inverter are presented which can significantly increase the power density under automotive conditions. Because of the relative high price of SiC-MOSFETs compared to Si the main goal is to reduce the number of utilized SiC-devices at same current rating. In order to achieve this, studies are performed to find the best approach for improving the thermal management and finally the whole inverter was designed under these aspects. In a final study the improvements of the investigations and redesigns are compared regarding thermal resistance, temperature uniformity of chips and overall temperatures.