A direct bonding copper degradation monitoring method for insulated gate bipolar transistor modules: Boundary‐dependent thermal network combined with feedback control

The direct bonding copper (DBC) substrates of insulated gate bipolar transistor (IGBT) modules degrade inevitably under cycling thermo-mechanical stress, causing potential threat to the reliability IGBT modules. However, little attention has been paid monitoring their degradation. This paper proposes a DBC degradation method for modules, which combines boundary-dependent thermal network and feedback control. A is employed describe internal material can be extracted from finite-element model. boundary conditions including power losses are considered, enabling suitable various working different characterised by its equivalent conductivities measured in ageing experiments. On basis network, control applied monitor regulating impedances. Finally, proposed model verified effectiveness accuracy junction temperature calculation. casts new light on modelling could provide feasible