Electro-thermal Coupling Simulation For IGBT Module Based On Saber

IGBT is the most widely used power switching device now.Because of its many advantages,such as high current density,low saturation voltage drop and so on,it has been widely used in the process of energy conversion.The working environment of IGBT is often very bad,such as high voltage,high current intensity,high switching frequency,so that the power dissipation and junction temperature of IGBT is high.However,there is a strong coupling between the electrical characteristics of the IGBT and the junction temperature,that is,the electrical characteristics of IGBT are affected by the temperature,and its power dissipation will affect the junction temperature.Therefore,when using IGBT to design and simulate high power electronic circuits,we must consider both the electricity and heat,and consider the interaction between them.Therefore,this paper establishes the IGBT model based on MAST language in Saber simulation environment.Combined with the accurate equivalent heat transfer model,the electro-thermal simulation is carried out.First of all,this paper systematically describes the working principle of IGBT.As a P-N-P-N four layer structure,IGBT can be simplified as a combination of a MOSFET and a PNP tube.There are both electrons and holes in IGBT.This paper also gives a brief description of the common technical parameters of IGBT,and introduces the characteristics of IGBT module and its packaging structure.Secondly,on the basis of understanding the three basic concepts of heat transfer and thermal resistance,this paper analyzes the hierarchical encapsulation structure and heat transfer path of IGBT module,and points out that the main heat dissipation path is vertical.On this basis,a one-dimensional equivalent heat transfer model of IGBT module is established,and the RC parameters in the thermal model are extracted.Thirdly,this paper clarifies the power dissipation calculation model in the self-built behavior model.According to the electrical characteristics and equivalent circuit of IGBT,based on Saber simulation environment,two IGBT electro-thermal coupling simulation models are modeled by MAST HDL.Finally,two IGBT models established in this paper are placed in the circuit system to finish the electro-thermal simulation.This paper analyses the simulation results to verify thecorrectness of the models.The results show that the models in the paper can be used for real-time analysis on the change of electrical properties and the junction temperature of IGBT,and have a certain coupling relationship between electrical properties and junction temperature.The models established in this paper have the advantages of easy extraction of parameters and fast simulation speed,which can provide the basis for the selection,application design and reliability analysis of IGBT.