Optimization of a High Power-Density Inverter for Automotive Applications by Means of Top-Side Cooled Power Devices

The aim of this paper is to discuss the thermal modeling and simulations performed in the design and the development of a full electro-mechanical leveling system based on wide band-gap power devices operating at high voltage based on top-side cooled transistors. Due to the installation location of the electronic control unit (ECU), only air cooling is suitable. For this reason, a good thermal modeling is crucial to allow correct sizing of the whole power stage. The usage of power transistors installed into top-side cooled package eased the task, but the thermal behavior of the whole system has to be verified. The document describes how the thermal models have been done and simulated at two different levels: first, focusing on the chip to evaluate the performance of the package available on the market; second, focusing on the whole ECU for estimating the capabilities of the unit under operating conditions.