Introduction of Active Capacitance Control and Active Parasitic Inductance Control for Zero Overvoltage Switching

Zero Overvoltage Switching (ZOS) is a method that enables transistors to perform turn-off transitions at maximum speed, thereby minimizing switching losses, while simultaneously preventing overvoltage oscillations despite the high switching speed. However, only discrete turn-off current values exist where ZOS is applicable. This paper presents novel techniques to broaden the operational area where ZOS can be utilized. This is accomplished with active control of resonant elements. The range of options for further turn-off currents where ZOS is applicable is outlined and evidenced by tests conducted on a prototype. This approach not only increases the versatility of ZOS but also improves its applicability in power electronic systems.