中文摘要：

目前在双馈风电机组（doubly-fed induction generator,DFIG）对称短路暂态特性的研究中,未充分考虑DFIG网侧变流器控制以及机端电压相位跳变等因素。为此,首先建立了综合考虑上述2种因素的DFIG故障暂态模型,在此基础上,推导了电网三相对称故障情况下的DFIG转子电流和定子电流的瞬时表达式,分析了DFIG机端电压相位跳变以及DFIG网侧变流器控制在故障时对短路电流的作用机理,实现了电网故障下DFIG故障暂态过程更为准确的描述。时域仿真与动模实验结果均验证了短路电流表达式的正确性。

英文摘要：

At present in the research on transient characteristics of doubly fed induction generator（DFIG） under symmetrical short circuit fault in external power grid, such factors as grid-side converter control of DFIG and phase-angle jump of DFIG＇s terminal voltage are not fully considered. For this reason, firstly a transient model of DFIG fault, in which above-mentioned two factors are taken into account synthetically, is established; on this basis, instantaneous expressions for stator current and rotor current of DFIG under three-phase symmetrical fault occurred in power grid are derived, and the impacting mechanism of phase-angle jump of DFIG terminal voltage and grid-side converter control on short-circuit current during symmetrical short circuit fault in external power grid is analyzed, thus a more accurate description on transient process in DFIG under fault in external power grid is given. The correctness of the given expressions for short-circuit current is validated by results of both time-domain simulation and dynamic simulation experiments.