定子匝间短路故障下的双馈风力发电系统的小干扰稳定分析

Small-Signal Stability Analysis of Doubly-Fed Wind Power System under SWITSC Faulty Condition

建立了双馈电机(Doubly Fed Induction Generator,DFIG)在正常运行情况下和故障情况下的数学模型,并结合轴系部分和桨距角控制部分建立DFIG组的小干扰稳定模型。改变外界条件和内部状态(如风速和短路比),基于Lyapunov稳定性理论判定DFIG组是否稳定,并观察特征值的变化轨迹。同时为分析每个特征值的影响因素,引入参与因子。最后结合仿真验证,结果表明:一定条件下SWITSC故障对DFIG组稳定性影响是可以接受的。

Two mathematical models of DFIG under the healthy and faulty with Stator Winding Inter-turn Short Circuit （SWITSC） condition respectively were developed. Then combined the wind turbine drive train model and pitch control system for the small-signal stability studies. Changed the external conditions and internal state （such as wind speed and short circuit ratio varied）, infering whether the DFIG wind power system was stable by Lyapunov stability theory, then observe the eigenvalue loci. To analyze the impact parameters, introduced the participation factors. The computer simulations were applied to validate the conclusions. The results showed that the effect of SWITSC fault to DFIG wind power system could be accepted within a certain range.