High Power Converter Busbar in the New Era of Wide-Band-Gap Power Semiconductor

The busbar is crucial in high-power converters to interconnect high-current and high-voltage subcomponents. This paper reviews the state-of-the-art busbar design and provides design guidance in planar, laminated, and PCB-based busbars. WBG power semiconductor devices have much higher switching speeds than silicon power devices, making them more sensitive to parasitics; hence this will affect the design of the busbar. The skin depth at a higher frequency is much thinner; again, it will affect the choice. PCB busbar is becoming an attractive solution even for 100kW-200kW high-power converters because it can effectively reduce the loop inductance, improve the high-frequency current carrying capacity and reduce the cost. It can integrate other components, such as sensors, resistors, etc. much easier and brings additional system benefits.