Life Prediction Method for Power Device of Traction Inverter in Metros

Insulated Gate Bipolar Transistors (IGBTs) are the key components of the traction inverter in metros. However, due to the complex operating conditions and environment of metros, IGBT modules are frequently subjected to thermal and mechanical stress impact and are prone to wear-out failure. This paper focuses on the residual life prediction of IGBT modules under the actual mission profile of metros. Firstly, the traditional life prediction method of IGBT modules is studied in details. Then, considering the solder layer fatigue can accelerate the wear-out failure rate of IGBT devices, an improved residual-life-prediction method of IGBT modules is proposed. Finally, simulation results have compared and verified the effective of the improved residual life-prediction method. The results showed that compared with the traditional life prediction method, the performance of the improved method is much closed to the actual condition, the traditional life prediction method overestimates the residual life of IGBT module.