Establishment method of IGBT thermal network model based on electrothermal coupling simulation and parameter identification

Abstract To swiftly and precisely assess the IGBT’s thermal safety during the circuit design phase, this paper proposes a method of establishing an IGBT thermal network model by electrothermal coupling simulation and parameter identification. This model integrates electrothermal coupling simulation techniques and parameter identification methods. Firstly, the IGBT’s finite element model is established by COMSOL, aiming to acquire the temperature distribution patterns of the IGBT and its heat sink under various operating conditions. Then, the objective function of parameter identification is constructed. The IGBT thermal network model’s parameters are extracted by combining the electrothermal coupling simulation results with the primal-dual interior point method. Then the device’s junction-ambient thermal network model is obtained. The proposed method’s efficacy is validated through the comparison of the results and calculation time of the thermal network model and the electrothermal coupling simulation.