中文摘要：

电网电压跌落在双馈感应发电机（DFIG）定、转子绕组中激发的电磁暂态过程是影响DFIG和电网安全的重要因素,因此,定量分析电压跌落后DFIG的电磁暂态过程具有重要意义。以DFIG电压完全跌落后的物理过程分析为基础,研究了DFIG在三相短路后的磁链初值平衡电路、电流频率特性以及定、转子电流中各频率成分之间的依存关系。根据磁链平衡电路,求解得到了三相短路电流的解析表达式,提出了DFIG三相短路电流的解析计算模型,统一了三相短路过程中频率成分、衰减时间常数、幅值和初相位的分析结论,并通过解析模型与DFIG经典模型的仿真对比验证了模型的有效性。

英文摘要：

The power system short-circuit capacity grows with the increasing of penetration power from wind farm based on doubly-fed induction generator（DFIG）.Thus,it is important to analyze the short-circuit current from wind farm quantitatively in relay setting and breaker switching.Based on the analysis of physical processes following the short-circuit fault of DFIG,the balance circuit of initial fluxes,components of frequencies and the dependent relationship between stator current and rotor current are studied.By solving the flux circuits,an analytic expression and practical calculation method for the short-circuit current are obtained and the perspectives on frequency components,decay time constants,amplitude and initial phase are unified.The practical model simulation results compared with detail model show that the practical model can accurately describe the short circuit current for DFIG.