An Improved Thermal Network Model of the IGBT Module for Wind Power Converters Considering the Effects of Base-Plate Solder Fatigue

This paper presents an improved thermal network model of insulated-gate bipolar transistor (IGBT) module, which considers the effects of base-plate solder fatigue on the junction temperature of the said module used in wind power converters. First, the coupling thermal structure 3-D finite-element model of the IGBT module is established based on the structure and material parameters of the module used in the wind power converters of a doubly fed induction generator. The junction temperature of the module is investigated at different thermal desquamating degrees of the base-plate solder. Second, the thermal resistance parameters are determined at different desquamating degrees, and the improved thermal network model that considers the effects of the base-plate solder fatigue is established. Finally, the IGBT junction temperature results through the improved thermal network, and the 3-D FEM models are compared.