矿用高压变频器中IGBT模块在阶跃脉冲下局部放电特性

针对矿用高压变频器常因 IGBT 模块内部发生局部放电而导致故障的原因和特性进行了研究。 本文从微观角度观察了 IGBT 模块局部放电发生位置的结构特点,发现其结构绝缘薄弱处在高斜率阶跃脉冲作用下易发生局部放电现象;建立了 IGBT 模块在阶跃脉冲作用下的局部放电过程模型,揭示其发生局部放电的机理;搭建实验平台,测试 IGBT 模块在单个脉冲作用下的局部放电特性。 实验结果表明,脉冲的上升时间、脉冲宽度是影响局部放电起始电压的主要因素;根据实验数据的分析,提出了预测局部放电起始电压的计算公式。 研究结果可为煤矿电力电子设备 IGBT 模块的绝缘设计和使用时的电压限制提供参考依据。

Partial discharge characteristics of IGBT module in mine frequency converter under step pulse

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.