Non-dissipative snubber design for AC/DC converters by using resonant techniques

One of the main objectives of the design of power converters working at high frequencies is the reduction of the switching losses in the semiconductor devices, looking for a better efficiency or a further increase in the working frequency. The resonant techniques have been developed as a way of reducing these losses. This paper describes a non-dissipative snubber applied to a 5 kW AC/DC converter, controlled by means of an IGBT, working at a frequency of 20 kHz and using quasi-resonant switching techniques. The paper analyses the working conditions of the switching device, explaining the special features of the control strategy, derived from the resonant behaviour of the converter