中文摘要：

本文针对两单元并联集成三相交直流变流电路,推导出其在正弦脉宽调制（SPWM）下的一般仿射方程.通过微分同调原理得到了降阶化简的判定条件和主要等值参数算法.通过混沌分析的轨迹图描述了系统参数与不同条件的关系,并针对该电路进行特征值计算,证实该方法可以回避特征值的直接求解而降阶系统.最后,根据上述参数进行仿真分析,验证了近似化简方法的有效性和适用范围.

英文摘要：

Integrated three-phase AC-DC system is widely used in modern society with series of base units.In this paper we deduce a general equation of the system in an affine coordination in order to use the differential geometry.Firstly,a new approximate equivalence method is presented by differential homology,including the judgment criterion and the main parameters of the equivalent model.Besides,the chaotic analysis relates different parameters to different situations which can accurately be simulated by PSCAD/EMTDC.And then calculation of eigenvalue indicates that the equivalence method is useful and simple.Finally,a simulation shows the accuracy and the applicability of the method.