母排杂散电感对IGBT模块功率端子不均流影响

摘要

IHM-B封装绝缘栅双极型晶体管(IGBT)模块有3组功率端子,其内部可等效为3组IGBT并联.母排杂散电感的分布对流进该模块功率端子电流的不均流程度有很大影响.以一种半桥式结构的母排作为研究对象,建立影响IHM-B封装的IGBT模块功率端子间不均流程度杂散电感的等效数学模型.通过Q3D有限元仿真软件提取出该母排的自感与互感.搭建双脉冲测试电路,分别提取出在开通瞬态某一时刻流进该IGBT模块3组端子的电流变化率的实验数据,进而分析母排杂散电感对IGBT模块功率端子不均流的影响.实验分析结果证明,通过改变母排结构以减小等效杂散电感的差异,能很好地消除功率端子不均流现象.%Insulated gate biopolar transistor(IGBT) module of IHM-B encapsulation has three groups of power terminal which can be equivalent to three sets of IGBT in parallel.The distribution of busbar stray inductance has much of effect on the current uneven flow through power terminals.Based on a half bridge structure of busbar,an equivalent mathematical model of stray inductance is presented which impact the degree of uneven current distribution on IHM-B encapsulation of IGBT module power terminal.The self and mutual inductances are extracted by Q3D-a finite element stimulation software to calculate the equivalent inductance.Set up double pulse test circuit and extracted experimental data of current rate at a certain moment flow into the three groups of power terminal of the IGBT module respectively to analyze busbar stray inductance to the influence of uneven current flow power terminals.The experimental analysis result shows that by changing the structure of busbar to minimize the difference of equivalent stray inductance,the phenomenon of uneven current from power terminal can be well eliminated.