Heat Dissipation Performance Analysis of IGBT Module for Flexible HVDC Converter Valve Based on Field-Circuit Combined Simulation

At present, most Voltage Source Converter (VSC) in known flexible HVDC transmission project adopt modular Multi-Level Converter (MMC). Insulated Gate Bipolar Transistor (IGBT) module is the key device in MMC. In this paper, field-circuit combined simulation is carried out for welded IGBT modules. Firstly, a simulation model of the MMC circuit is created in the PSCAD/EMTDC platform. The model is used to calculate the current and voltage drop of the IGBT module under certain operating conditions. Then, the loss power is calculated using the loss calculation formula of IGBT module. The calculated results are substituted into the established finite element simulation model of the IGBT module as the heat source. Finally, the temperature field distribution of IGBT modules under certain operating conditions is obtained. The necessity of heat sink in IGBT module is also analyzed. The model built in this paper can provide a model basis for the subsequent study of the reliability of flexible HVDC converter valve IGBT modules.