大规模风电并网时双馈风机无功出力研究

Research of Reactive Power Output of Doubly-fed Induction Generator When Large-scale Wind Power Integration

为了减少大规模风电并网时在无功补偿设备上的投资,在采用双馈风机的风电场中,应当充分利用双馈风机本身发出无功功率的能力。将双馈风机发出无功的能力与无功补偿设备配合使用,提高风电场的运行效益。首先分析了双馈风力发电机无功发出极限,考虑风机定子、转子的无功出力约束及机组运行稳定性的限制。其次介绍了无功功率的控制与分配问题,通过一套综合的无功控制系统,采用了按照剩余无功极限比例分配的方法在各个机组之间分配无功,使所需的无功补偿设备大大减少,从而提高了风电场运行的经济性。

In order to decrease the investment on reactive power compensation equipment when the large scale wind power connected to the network and decrease the burden on economy, the capability of providing reactive power of DFIG should be fully used. To combine the capability of providing reactive power of DFIG with the reactive power compensation equipment, the operational benefits should be improved greatly. Firstly, the article analyzes the reactive power limit of DFIG, considering the limit of stator and rotor, and the stability of the DFIG is also con- sidered. And then, the article introduces the control and the distribution of the reactive power. A comprehensive set of reactive power control system and the distribution method in accordance with the proportion of the remaining reactive limit are proposed. In this way, the reactive power compensation capacity of DFIG is used first, the use of reactive power compensation equipments are greatly reduced, so the economy of the wind farm is obviously im- proved.