An Easy-to-Implement Flexible Commutation Design With Reduced Switching Losses, $di/dt$ and $dv/dt$ for High-Speed and High-Power IGBTs

The high-frequency and high-power operation of power converters has imposed stringent requirements on the switching loss and electromagnetic interference (EMI) performance of power devices, particularly for the increasingly popular high-speed insulated gate bipolar transistors (IGBTs). Conventional soft switching techniques with snubbers encounter significant challenges in high-frequency and high-power scenarios due to their inherent complexity and the substantial influence of parasitic parameters. This paper presents an easy-to-implement flexible commutation design aimed at reducing switching losses, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$di/dt$</tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$dv/dt$</tex-math></inline-formula> simultaneously in high-speed power IGBTs for high-frequency and high-power applications. The proposed design includes a snubber capacitor and two printed-circuit-board (PCB)-based coupled inductors as the busbar, facilitating soft switching conditions for the IGBTs, along with a lossless energy recovery circuit to achieve lossless operations. Importantly, the design incorporates only passive components and specially utilizes distributed parasitic parameters, ensuring both ease of implementation and high performance. The proposed design is experimentally validated through double pulse tests (DPTs) using a high-power and high-speed IGBT rated at 1.2kV/140A, with the switching performance analyzed comprehensively in comparison to a conventional hard-switching design.