中文摘要：

提出基于双馈式风电机组（DFIG）变频器的无功协调控制策略,以提供足够的无功功率来维持系统稳定。在DigSILENT/PowerFactory平台上,搭建风电场的详细模型,通过协调风电机组网侧和转子侧的无功功率参考值,改善风电机组的输出有功和无功功率;采用特征值分析方法,分析大型风电场在采用无功协调控制策略后,对电力系统低频振荡和小扰动稳定性的影响。仿真结果表明,该策略通过自动调节风电机组发出的无功功率,改善了DFIG的输出特性,提高了风电场的输出有功功率（通过稳定机端电压实现）,对故障过程中风电机组的连锁脱网有一定抑制作用。

英文摘要：

A coordinated var control strategy based on the converter of DFIG（Doubly-Fed Induction Generator） is proposed to provide sufficient reactive power for system stability.A comprehensive DFIG model is built on DigSILENT / PowerFactory platform and the active and reactive power outputs of DFIG are improved by coordinating the grid side and rotor side reactive power references of DFIG.The eigenvalue analysis method is used to analyze the impact of large-scale wind farm applying the coordinated var control strategy on the low-frequency oscillation and small signal stability of power system.Simulative results show that,with the proposed control strategy,the output characteristics of DFIG are improved through the automatic regulation of the reactive power generated by wind farm,the active power output of wind farm is increased（by stabilizing the terminal voltage）,and the cascading trip-off of DFIG from grid is suppressed.