大规模风力发电对电力系统的影响

Influences of large-scale wind energy converters on transmission systems

风电电源由于其自身特点,当风电装机容量占总电网容量的比例较大时对输电网的安全和经济运行都会带来冲击。德国的风力发电大部分位于海边风力资源充裕的地方,远离负荷中心,大风天气时风电出力增加,会造成严重的输电瓶颈。此外,大规模风力发电对系统小干扰稳定、频率稳定及电压稳定都有着不同程度的影响。风力发电功率输出的随机波动很大且不可控,预测精度较差,这对发电运行计划方式以及系统备用容量也都提出了新的要求。

Wind energy is a reliable and well developed renewable energy, which has undergone rapid growth worldwide in recent years. The European countries, especially German government enacted laws to support the development of wind energy. Nowadays the installed capacity of wind energy converters already makes a significant portion of the total installed generation capacity in Germany. Because of its special characteristics, a large-scale wind energy injection means a great challenge for the security and the economic operation of transmission systems. The wind energy converters in Germany are mainly located on coastal areas, where are far away from the load centres. Severe transmission congestion may occur during blustery weather. To different extents, the large-scale wind energy injection affects small signal stability, frequency stability, as well as voltage stability, Furthermore, wind energy injection has a significant stochastic fluctuation, which is incontrollable and difficult to forecast. This aspect brings new requirements for economic generation dispatching as well as system reserve capacities.