严重故障下DFIG风电场低电压穿越改进控制研究

A Improved Control Strategy of DFIG Wind Farm for Low Voltage Ride Through During Serious Fault

增加Crowbar电阻起动时,DFIG将工作于普通异步机模式,从系统中吸收大量无功功率。为改变这种情况,提出了一种更能充分利用双馈风机无功容量的协调控制方式,为系统提供无功功率,从而提高系统的暂态电压稳定性。仿真结果验证了交直流保护电路配合使用的优点及可行性,所提出的无功协调控制不仅有利于系统电压快速恢复,还能减少风电场动态无功补偿装置的安装容量,从而节省投资。

The DFIG becomes a conventional induction generator and starts to absorb reactive power, delaying the process of rebuilding the grid voltage. A new fast coordinated control scheme of STATCOM and DFIG was proposed for minimizing the capacity of centralized reactive power compensation device and making the best use of the reactive power control capability of DFIG. Simulation results show that the feasibility and advantage of the AC/DC protection for Low Voltage Ride Through during serious fault. The proposed coordinated control scheme can not only improve the transient voltage stability, but also help reducing the capacity of STATCOM so that the cost of investments in wind farms would be reduced.