适合风电特性的联络线过载切机装置控制策略

Control Strategy of Tie-lines Equipped with Overload Safety Device Adapted for Wind Power Characteristics

在PowerFactory仿真软件中建立了一个含风电场群的实际电网的短路计算模型,对风电群内带或不带低压穿越能力的风电场在联络线发生故障时的电磁暂态过程和保护动作情况进行仿真,分析了该过程与水电、火电等常规电源并网联络线故障过程的差异。在此基础上,提出一种适合风电特点的联络线过载切机装置的控制策略。该策略对故障线路的识别、过载切机时机的选择进行了针对性设计,可有效识别故障线路和非故障线路,并在适宜时机切除风电场,从而提高风电并网联络线的输送能力和供电可靠性。

A short-circuit calculating model of an actual power network integrated with wind farm group is built with the PowerFactory simulation software. The electromagnetic-transient behavior and the relay action of different wind farms with or without the low voltage ride through （LVRT） capability in the wind farm group are analyzed to compare with the traditional electric power,such as the hydroelectricity or the heat electricity. Based on the studies,a control strategy of the tie-lines equipped with overload safety device adapted for the wind power characteristics is proposed. The control strategy is designed for the discrimination of the faulty line and the choice of the right cutoff time,which significantly improves the transmitting capability and the reliability of the tie-lines of wind farms.