从输电阻塞角度建立的风电场容量可信度模型

风电并网时既要考虑系统的可靠性又要考虑输电阻塞。目前风电场容量可信度仅从可靠性单一角度提出。为此从输电阻塞角度提出了风电场容量可信度的定义;通过Monte Carlo法建立计及元件故障(发电机、线路和变压器)的风电场容量可信度模型,并提出该模型的二分法求解算法;同时还提出了风电阻塞指标以描述风电场并入电力系统对缓解系统输电阻塞的贡献。通过对修改的IEEE-RTS进行算例分析,验证了方法的正确性和实用性。结果表明:系统阻塞状况的缓解程度与并入风电场的位置有关,风电场容量可信度和风电阻塞指标相结合可以评价风电场并网对系统阻塞状况改善的有效性和经济性。

Wind-farm capacity-credit model considering transmission congestion

Both reliability and transmission congestion should be considered when a wind farm is connected to a power system. Nevertheless, wind-farm capacity credit (CC) is defined currently considering reliability only. In this work, we proposed a wind-farm CC definition based on transmission congestion, built a CC model taking into account the random failures of power system components (generating units, transmission lines and transformers) using Monte Carlo technique, and proposed a solution algorithm of CC model using the bisection method. We also proposed wind power congestion indices to describe the contribution of a wind farm incorporated into a power system to alleviating transmission congestion. The case studies on a modified IEEE-RTS indicate that the proposed method is effective and feasible. The results show that for a power system, alleviation of transmission congestion is related to the wind-farm location, the combination of CC and wind power congestion indices can evaluate the effectiveness and economical efficiency of a wind farm in alleviating transmission congestion.