Degradation of power semiconductor modules for trains

Various electronic equipment including traction converters is installed in railway vehicles. It is important to improve the reliability of each element constituting the equipment. To obtain the data required for the maintenance and renewal work of traction converters mounted on recent EMUs, we developed a new method to estimate the degradation of power semiconductor modules, which are one of the parts of the converters. In this paper, the results of thermal resistance measurements are reported and degradation estimation for high-voltage / high-current IGBT modules is discussed.