Reliability Considerations for Parallel Performance of Semiconductor Switches in High-Power Switching Power Supplies

In order to ensure increasing current rating of semiconductor switches, paralleling is unavoidable. In this paper, the paralleling of switches has been studied from the reliability point of view. A prototype 4-kW boost converter has been used for this paper. In this boost converter, five insulated gate bipolar transistors are paralleled per switch in order to increase the current rating. Based on experimental results, the reliability of converter has been calculated. Results of reliability calculations showed that paralleling switches extremely decreases reliability of DC-DC converters. The same converter has been constructed by using an integrated power module (IPM). The same calculations have been repeated for the IPM-based converter. The comparison of the results shows that the case of IPM in converters can increase the reliability of the circuit.