Abstract: The partial discharge occurs in IGBT device module of mine equipment. which leads to the breakdown of insulation and burns the device. In this paper the causes and characteristics of pd in IGBT module were studied. Therefore,based on the research of material structure,the partial discharge process model for the internal circuit of IGBT device module in coal mine equipment,which is under ultra-high slope pulse square wave, is innovatively proposed and verified by experiments. Then, the partial discharge characteristics of the device module under monopulse or repeated pulses are tested by the experimental platform,and the influence of the pulse rise time and pulse width on the partial discharge of the internal circuit of the device module is analyzed. According to the experiment results of partial discharge under a single pulse,the prediction formula for predicting and calculating the partial discharge initial voltage is innovatively proposed and verified. A certain reference for the insulation design and performance conditions of IGBT device modules in mine equipment is provided.