中文摘要：

针对由具有动态无功调节能力的变速恒频风电机组（包括变速恒频双馈异步风电机组和直驱永磁同步风电机组）组成的风电场，提出了一种新的电压无功分层控制策略。该策略由风电场局部区域某节点电压与参考值的偏差得到整个风电场的无功功率需求，并按等功率因数算法分配给各台风电机组，作为其无功功率控制目标参考值。参考值的实时整定过程考虑了风电场无功功率输出约束和功率因数约束。算例表明，所提出的策略既可抑制由周边负荷变化引起的控制点母线电压波动，又可抵御由局部电网故障造成的控制点电压跌落，具有维持风电场接入局部区域电网电压稳定的作用。

英文摘要：

This paper proposes a hierarchical structure reactive power control strategy to solve the voltage stability problem caused by wind farm integration. The reactive power demand of the wind farm is calculated based on the deviation of reference voltage and measured voltage at the control point. The target reactive power for each individual wind turbine is calculated using the equal power factor algorithm. In this way, the voltage stability of grid integrated wind farms can be improved. The reactive power and power factor limits are considered in real time during the whole control strategy process. Simulation results on the New England 39-bus system show that the presented strategy can support the voltage at the control point and can restrain voltage dips caused by local network faults.