采用网侧TCVR的双馈风机低电压穿越控制策略研究

Low voltage ride-through control strategy of a DFIG with grid-side thyristor controlled voltage regulator

随着风电并网容量的快速增加以及海上风电的发展,风电机组在故障期间的并网运行特性更加受到关注。采用了一种比较简单的双馈型风力发电机组的低电压过渡方案。在风电场变电站的低压侧安装晶闸管控制电压调节器(TCVR),当电网电压跌落时,根据电网电压下降的幅度对网侧电压进行合理补偿,提高双馈电机定子侧电压。在PSCAD/EMTDC中建立了5 MW双馈风电系统的模型,应用所提的控制方法,对风电机组在严重对称故障下的运行特性进行仿真,验证了所提方法的有效性。

With the rapidly increasing capacity of grid-connected wind power and the development of offshore wind power, the operating characteristics of wind turbine during the fault have drawn more concern. This paper adopts a relatively simple method to achieve low voltage ride-through （LVRT） of doubly-fed induction generator （DFIG） based wind turbine. A thyristor controlled voltage regulator （TCVR） is installed in the low-voltage side of the wind farm substation. When voltage dip occurs, the grid-side voltage is reasonably compensated according to the degree it drops to improve the stator voltage of DFIG. A 5MW DFIG wind power system model with the proposed control strategy is estab- lished in PSCAD/EMTDC to simulate the operating characteristics of the wind turbine under severe symmetrical fault to verify the validity of the proposed method.