Elimination of transistor’s switching losses by diode reverse recovery in dedicated application

This paper deals with reverse recovery effect of various diodespsila structures and its elimination in dedicated applications. In principle it deals with the commutation process between transistorpsilas turn-on and diodepsilas turn-off in DC/DC converters. Quantification of received data was based on experimental measurements and consequently was converted into continuous form for graphic interpretation in dependence on switching frequency, supply voltage and load current. Accordingly, the utilization of new progressive materials of power semiconductor devices based on SiC technology is being described. It is concerned SiC Schottky Barrier Rectifiers diode structures versus Si UltraFast and HyperFast diodes rated for 600 V. From measurements is clear to say that selection of suitable diode could perfectly eliminate almost all of the turn - on losses without usage of soft - commutation. However the limiting factors of diode selection further remains parameters of power circuit as well as switching frequency whereby from measurements results that by influence of worser dynamic properties of diodes at low frequencies the losses will be plumbless.