Humidity in Traction Converters

Traction converters for railway applications require long life times and have to cope with rough environmental conditions. In this report we will focus on a model to calculate the humidity inside traction converter cabinets based on the external conditions. With the calculated humidity in an application the humidity related lifetime of IGBT modules can be calculated. The model presented in this paper takes several physical effects into account like humidity absorption in plastic materials, adsorption on walls and condensation. Furthermore we will show the correlation of the calculations with experiments.