Xiangxiang Liu 1,2, Lingling Li 1, Diganta Das 2, Michael Pecht 2
1 State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Hebei University of Technology, Tianjin 300000, China
2 Center for Advanced Life Cycle Engineering (CALCE), University of Maryland, College Park, MD 20742, USA
Insulated gate bipolar transistor (IGBT) is widely used in a variety of applications, many of them are safetycritical.
The failure of the IGBT accounts for a significant portion of the failures in the converter. An electrothermal
model is useful for predicting the junction temperature in power electronic components and modules.
The model parameters change with degradation, but parameters of such models are not readily available in the
literature or in the parts documentation. In this work, various combinations of parameters, source voltage,
junction temperature, gate voltage, collector current, gate resistance, and frequency are developed and executed,
and the electro-thermal model parameters are derived from these experimental results. The change of switching
power loss and thermal resistance with degradation is derived from accelerated aging experiments that combine
temperature and current. The results show that degradation in the thermal resistance over a period of
9000 cycles can increase the junction temperature by more than 20% compared with the original junction and
case temperature difference. Degradation at the die level can cause a 50% increase in the switching power loss
compared with the original switching power loss under the same working conditions. The electro-thermal model
and parametric degradation model are applied in the sine pulse width modulation (SPWM) simulate circuit to
improve the accuracy of temperature prediction after degradation.