Research on Life Prediction of Key Component IGBT of the Traction Converter for Electric Multiple Units

The traction converter is the core component of an electric multiple unit (EMU), with the Insulated-Gate Bipolar Transistor (IGBT) serving as the key element that directly determines the operational status of the entire traction system. Predicting IGBT service life is therefore essential for fault prediction and health management in trains, providing critical support for ensuring operational safety, guiding condition-based maintenance decisions, and reducing life-cycle costs. In this study, we summarize the basic structure and failure mechanisms of IGBTs and propose a theoretical relationship between their performance parameters and degrees of aging, subsequently developing a method for predicting IGBT service life based on void ratio and service time. Additionally, a DC power cycle aging test is designed and carried out on the IGBT module according to the actual working conditions and the range of acceptable junction temperatures. The life prediction method proposed in this paper is used to analyze the test data, providing the predicted service life of the traction converter’s IGBT module. The results show that a new IGBT module can be used for 29.66 years or 17.8 million km, which can be used to support future maintenance work.