A novel switching algorithm to balance conduction losses in power semiconductor devices of full-bridge inverters

The power loss in switching devices plays an important role in design of static converters. The power dissipated during oil state of semiconductor switches (conduction loss) is a Substantial portion of the total switch losses. especially in low frequency converters. Conduction loss rnay differ in switches of the converter due to the difference in duration and amount of currents flowing through them. This is, in turn, the result of dissimilar switching signals applied to the switches. To optirnize the converter design. it is important to equalize the conduction losses of all main switches. In this paper it is shown that with conventional switching patterns in a full-brid,,e inverter (H-bridge cell). the switches carry different Current values. therefore they bear different power losses and get unequal temperature rises. To balance conduction losses, a novel switching method is proposed and its effectiveness and validity is examined by computer simulation results and experimental works. Copyright (C) 2008 John Wiley & Soils, Ltd.