Research on Thermal Impedance Modeling Method of IGBT Devices

The thermal impedance model of IGBT device plays an important role in accurately analyzing the transient temperature change of IGBT device. Because it is relatively difficult to measure the internal temperature of packaged IGBT devices and it is difficult to obtain the chip junction temperature directly, it has certain advantages to study the temperature characteristics of IGBT by simulation. A method to establish the thermal resistance model of devices through the thermal impedance test data or datasheet is presented in this paper. Firstly, the medium thermal resistance of the device packaging material is calibrated based on the three-dimensional structure model and material parameters. Secondly, the contact thermal resistance of the device is calibrated combined with the steady-state thermal resistance test data. Finally, the transient thermal resistance model is calibrated by modifying the material parameters. In order to verify the accuracy of the model, thermal simulation analysis is carried out after each calibration to verify the effectiveness of the modeling method. The method described in this paper has good practical significance, and it can provide a useful reference for temperature field modeling technology and simulation technology of IGBT device.