CHOPPER CIRCUIT

摘要

A snubber-assisted ZVZCT (Zero Voltage and Zero Current Transition) chopper circuit comprises two divided main reactors that equivalently constitute a single reactor; a main switch that has one of its terminals connected to an end of a series combination of the main reactors, while having the other end connected directly to one of the voltage terminals of a DC power supply; a series combination of a snubber diode and a snubber capacitor that is connected across the main switch; and an auxiliary switch connected between a junction of the snubber diode and the snubber capacitor and a junction of the two main reactors. This arrangement can eliminate the thermal loss that otherwise would occur at a reactor provided for a soft switching; improve the conversion efficiency; prevent the excessive current and excessive voltage during turning on and off the main switch; and prevent the excessive voltage that otherwise would be caused by a reverse recovery of an output diode.