New calorimetric power transistor soft-switching loss measurement based on accurate temperature rise monitoring

Modern GaN and SiC power semiconductors require new experimental methods for determining switching losses as the widely accepted double-pulse-test (DPT) fails to accurately capture the dissipated energy during a switching transition because of electrical measurement limitations imposed by the very fast switching of WBG devices. In this paper, a new calorimetric measurement principle which relies on temperature rise monitoring of an aluminum heat sink during continuous operation of the attached power semiconductor is presented. Unlike traditional calorimetric methods, a single measurement can be performed in minutes. Using the proposed measurement principle, a soft-switching performance evaluation of selected 600 V GaN, SiC and Si power transistors is provided.