中文摘要：

针对系统电压跌落的同时，部分并网风电场又发生某种短路故障进行了研究。文中对风力发电系统在同步旋转参考坐标系下的稳态和暂态进行数学建模。在MATLAB／SIMULINK的平台上满足持续并网的条件下，分析风电场在无故障和部分风机组发生短路故障时的完成系统低电压穿越的能力。并基于小波进行故障分析。依据各项仿真数据，得出结论：发生单相短路时，风电场能较稳定地进行穿越；而两相或三相短路时，在系统电压恢复瞬间将会有强烈的能量振荡和冲击电流，因此应尽可能在系统电压恢复前就切除故障。

英文摘要：

To analyze the short-circuit faults occurred in wind farm system while power system voltage drops, a mathematical dynamic model and a steady-state model of wind farm with DFIG are established in the synchronous rotary coordinates. In the condition of continuously connecting wind farm to grid and keeping power generation on the MATLAB/SIMUL1NK platform, the LVRT ability of wind farm without short-circuit fault or with short-circuit faults in some generators is analyzed, and wavelet-based fault analysis is performed. With simulation, some main electrical parameters are easily obtained. Conclusions can be drawn from the simulation results that： steady LVRT of wind farm system can be completed in the condition of single phase short-circuit fault; while the situation gets worse for two-phase or three-phase fault, where voltage recovers within a moment, and both wind farm and power system will endure a great deal of energy flow. So the faulty phase should be cut off before voltage recovery.