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电网故障持续过程中,低电压穿越导则要求风电场输出规定的无功电流以支撑电网电压恢复.目前电网运营商通常规定风电场配置一定容量的静态无功补偿装置(static synchronous compensator,STATCOM)来提供无功支撑,该文对配有STATCOM的风电场进行研究.为满足低压穿越要求,风电机组和STATCOM都需采用基于锁相环的电流矢量控制方法.但是在电网严重故障时,由于锁相环与风电场电流控制之间存在动态交互,风电场输出与电网存在同步失稳的风险.该文以双馈型发电机的(doubly fed induction generator,DFIG)风电场为例,分析了风电场的同步稳定机理和条件,得出实现风电场的同步稳定必须输出一定的有功电流.而STATCOM只能输出无功,因此需DFIG的协助才能实现同步稳定;同时受功率变流器输出能力的限制,DFIG无功输出能力减弱,需STATCOM协助才能满足并网导则的无功需求.基于此,提出一种DFIG和STATCOM的协同电流控制方法,根据电网传输线路阻抗角协调控制风电场输出电流的有功、无功分量,确保风电场同步于电网运行.最后通过仿真验证了理论分析和控制方法的有效性.“,”In grid code for wind power generation,wind farms are required to supply specified reactive current to support the recovery of the grid voltage during low voltage ride through (LVRT).Wind farms are usually required to be equipped with static synchronous compensator (STATCOM) by grid operators.In order to meet the requirements of LVRT,wind turbines and STATCOM usually use phase locked loop oriented current vector control method.However,wind farm output has a risk of losing synchronization with grid when severe voltage dip occurs because of the dynamic interaction between the phase locked loop (PLL) and current control.Based on doubly fed induction generator (DFIG) wind farm,this paper analyzes the mechanism and conditions of synchronization stability quantitatively,and finds that active current is indispensable.STATCOM must be assisted by DFIG because of having no active current output capacity,while considering the capacity of the converter,STATCOM must output enough reactive current to help DFIG to satisfy the grid code.Based on which,a coordinated current control method is proposed,which coordinates output active and reactive currents of wind farm according with impedance angle of transmission lines.Finally,the effectiveness of the theoretical analyses and the control method are verified by simulations.