Estimating the chip temperature in an inverter by measuring the temperature sensitive Miller plateau during turn-off

Inhalt:
Mechanical aging of the interconnection layers of a module leads to an increasing chip temperature during operation mode. To be able to measure this increased temperature, the influence of the tem-perature on the switching parameters during switching operation can be used. One of these tempera-ture sensitive switching parameters is the Miller plateau during turn-off [1]. In this paper, a Miller plat-eau related voltage is detected and stored during the turn-off event. The measurement is triggered by a signal of the desaturation detection instead of the turn-on signal of the IGBT in [1]. In this paper, the measurement circuit and the measurement results are presented.