Abstract Based on the threshold voltage method under small current conditions and in combination with the working principle of IGBT, this paper derives an expression for the junction temperature and on-state voltage. Subsequently, relevant measurement circuits, a constant current source circuit, and a voltage acquisition circuit are designed to establish a junction temperature measurement model. The measured junction temperature is then corrected using the square root of t method. Finally, an experimental platform is set up to achieve accurate measurement of IGBT junction temperature.
Wei et al. (2025) studied this question.