The accuracy of multi-physics simulation analysis of Press-Pack IGBT (PP-IGBT) devices is related to the failure simulation and reliability lifetime modeling. The existing finite element modeling of PP-IGBT devices only considers the coupling relationship between various physical fields. The temperature effects on the material properties are ignored, which may lead to errors in the stress evaluation of the PP-IGBT device between finite element simulation and actual operation.
This paper proposes a multi-physics coupling finite element modeling method for the PP-IGBT device by considering the temperature effect of materials. Firstly, the thermal conductivity and electrical conductivity of the packaging material in the PP-IGBT device are analyzed, and a finite element calculation method that considers the temperature effects of material properties is proposed. Secondly, the electrical, thermal, and mechanical coupling finite element model of the PP-IGBT device is established with temperature feedback. The performance of the PP-IGBT device is compared to the existing and proposed multi-physics coupling finite element model under power cycling conditions. Finally, the infrared temperature test platform of the PP-IGBT device is established to verify the effectiveness of the proposed finite element model. The results show that compared to the existing finite element model of the PP-IGBT device, the average errors of the proposed model are reduced by about 5%.