Switching Performance Evaluation of High-Power 1.7 kV SiC MOSFET Modules using a Common Busbar Design

Abstract:
The high dI/dt present while switching Silicon Carbide (SiC) MOSFET modules, coupled with power-loop stray inductance results in increased voltage overshoots and oscillatory switching behaviour. Thus, good module packaging, DC-link capacitor selection and busbar design are fundamental to maximise the benefits of SiC technology. This paper presents an experimental investigation into the switching performance for three 1.7 kV SiC MOSFET half-bridge modules, examining the effects of different module packages and their connection to an optimised busbar. Results show that minor design changes significantly impacted the total loop inductance, with changes from ∼30 nH to ∼12 nH reflected in major improvements to the obtained switching performance metrics.