Abstract:

With the development of SiC MOSFET,the multi-channel SiC solid-state power controller with this device as the core part is gradually applied in the field of high-power density.Due to its higher temperature rise and extreme ambient temperature,the demand for thermal management of products has also increased.Therefore,an accurate assessment of the internal heat distribution of the product is a prerequisite for the design of a high-performance multi-channel solid-state power controller.This article took the 12-channel solid-state power controller with rated voltage of 270 V and rated current of 240 A as the object,analyzed its thermal failure mechanism,and established a simplified finite element model.The steady-state and transient thermal simulations and verifications of the 120 A and 180 A derating working conditions were carried out respectively.The thermal simulation on 240 A full-load working conditions was performed,and thermal design optimization was made based on the simulation results and actual conditions.Finally,the full-load test of the optimized product was carried out to verify the correctness of the thermal simulation and design optimization.

Key words: SiC, solid-state power controller, thermal failure mechanism, thermal simulation, design optimization