Comparison of different switching modes in a 10 kW high frequency step down converter using IGBTs

A comparison of three switching methods-hard switching, zero current switching, and zero voltage switching-applied to the step-down converter is presented. The behavior of different types of insulated-gate bipolar transistors (IGBTs) in the applications mentioned is investigated. Furthermore, the problems of designing the passive components, e.g. the resonant inductors needed for soft switching, are described. These devices are of crucial importance as the switching frequency and power output rise, parasitic effects due to high-frequency operation are also reported to give an overview of the complete system behavior. A maximum switching frequency of 120 kHz has been reached at a power output of 10 kW in the zero current switching mode