IGBT电力电子系统小时间尺度动态性能分析与计算的电磁场-电路耦合模型

A Coupled 3D Finite Element-Circuit Model for the Numerical Analysis of Small Time Scale Transients of an Insulated Gate Bipolar Transistor Power Electronics Device

为了解决现有模型不完全适用于小时间尺度电力电子系统瞬态性能分析与计算的不足,建立用于IGBT电力电子系统小时间尺度动态特性分析、计算的三维电磁场-电路耦合计算模型,并提出其求解的迭代计算方法。为精确描述小时间尺度下IGBT内部瞬态电磁场及其分布规律,建立的IGBT本体三维有限元模型考虑位移电流、趋肤效应和引线邻近效应等复杂因素的影响;为考虑极小时间尺度下线路中杂散参数的电磁效应,高阶杂散参数电路模型采用多段等效电路模拟杂散参数的影响,同时采用谐态电磁场数值分析计算方法提取模型参数以考虑趋肤效应等的影响。基于IGBT内部电磁暂态过程的分析,提出一种改进的IGBT电路模型;为兼顾计算精度和计算时间的要求,提出等效高阶电路模型的一种降阶方法。仿真计算和实验测试结果证明了所建模型及求解方法的有效性和正确性。

To consider the effect of the displacement current and the skin effect of theelectromagnetic phenomenon as well the stray parameters in a small time scale electromagnetictransient,which are not properly muddled in the existing model,a coupled3D finite element-circuitmodel of an IGBT based power electronics device for its transient performance computation in smalland extreme small time scales is developed and an iterative solution methodology is proposed.In orderto describe the skin effect and displacement current,a three-dimensional(3D)finite element model ofIGBT is developed;In order to model the influence of stray parameters,a high-order distributed circuitmodel of the whole power electronics system is proposed,and the numerical method for strayparameters computation is included.From the analysis of the internal electromagnetic transient processof an IGBT,an improved IGBT circuit model is proposed.In order to balance the accuracy and thecomputational cost of the high order circuit model of a complete power electronics system,a reductionmethod is proposed.The comparisons between the simulated and tested results evidence thefeasibilities and merits of the proposed work.