Prediction of switching loss variations by averaged switch modeling

Abstract

An analytical averaged equivalent circuit model is derived revealing how dominant loss mechanisms vary with power converter operating point in a PWM converter. The model is based on the operational characteristics of power diodes and IGBTs. Laboratory experiments support the derived model and confirm that IGBT current tailing and diode reverse-recovery are indeed the most critical losses in a PWM converter. These losses are more significant at light load, hence reducing the energy capture of converters used in wind generation.