A multiple-switch high-voltage DC-DC converter

Series connection of power devices has evolved into a mature technique and is widely applied in RV de systems, Static and dynamic voltage balance is ensured by shunting individual devices with dissipative snubbers, The snubber losses become pronounced for increased operating frequencies and adversely affect power density, Capacitive snubbers do not exhibit these disadvantages, but they require a zero-voltage switching mode, Super-resonant power converters facilitate the principle of zero-voltage switching. A high-voltage de-de power converter with multiple series-connected devices is proposed, It allows the application of nondissipating snubbers to assist the voltage sharing between the multiple series-connected devices and lowers turn-off losses, Simulation results obtained with a circuit simulator are validated in an experimental converter operating with two series-connected devices, The behavior of the series connection is examined for MOSFET's and insulated gate bipolar transistors (IGBT's) by both experimental work with a 2-kW prototype and computer simulation, Applications can be found in traction and heavy industry, where the soft-switching converter is directly powered from a high-voltage source.