风力场中并网点电压稳定控制技术研究

Research on Voltage Stability Control Technology for Grid-connection Point in Wind Farm

为解决传统单一的风力系统电压控制方法无法解决多时间尺度波动以及电力系统多种类扰动问题,提出风力场中并网点电压稳定控制研究。釆用剩余的加速面积减去剩余的减速面积,得到能够使系统维持功角稳定的减速面积缺额,作为计算控制切机量的依据,通过暂态稳定预测及分析判定该电力系统是否处于稳定状态,实现电力系统暂态稳定应急控制;通过风力场群无功电压控制和风力场集群层控制策略,实现电力系统中风电场群电压的协调控制;通过紧急控制与协调控制相结合,完成风力场中并网点电压稳定控制。仿真结果表明,电压表现平稳且逐渐增加,电压趋近于电压指标,电压变化只有0.3%,迭代次数平均值为24.6次,恒功率因数控制技术计算过程中使用的时间平均值为157.46 ms,清除电网故障耗费的总功率平均值为772.05 MW。

To solve the problem that the traditional single voltage control method for a wind power system cannot suppress multi-time scale fluctuations as well as many kinds of disturbance in power systems, the voltage stability control of grid-connection point in a wind farm is proposed. By subtracting the remaining deceleration area from the remaining acceleration area, the deceleration area deficiency which can make the power angle stable is obtained, providing a basis for calculating the control cut-off amount. The prediction and analysis of transient stability is used to determine whether the power system is in a stable state, thereby realizing its transient stability emergency control. Through the control of reactive voltage of the wind farm group and the control strategy for the wind farm group layer, the coordinated control of wind farm group voltage in the power system is realized. Moreover, through the combination of emergency control and coordinated control, the voltage stability control of grid-connection point in the wind farm is completed. Simulation re sults show that the performance of voltage is stable and gradually increases, tending to be close to the voltage index with a change of only 0.3%. The average number of iterations is 24.6, the average time consumed in the calculation using the constant-power factor control technology is 157.46 ms, and the average total power consumed in clearing grid faults is 772.05 MW.