500 kV统一潮流控制器在苏州南部电网的工程应用

报道了500 kV统一潮流控制器（unified power flow controller，UPFC）示范工程在苏州南部电网的应用情况，工程于2017年年底建成投产，建成后将成为世界上电压等级最高、容量最大的UPFC工程。首先介绍了苏州南部500 kV电网发展概况和存在的问题，分析了利用常规解决措施（线路导线增容、新增输电通道）解决上述问题时遇到的困难。然后给出了利用UPFC解决苏州南部500kV电网中存在问题的方案，详细论述了在苏州南部500kV电网应用UPFC的接入方案、接入效果、工程实施难度和投资成本。最后通过技术经济比较，分析了苏州南部UPFC示范工程的经济效益和社会效益。分析结果显示，示范工程投运后可以有效缓解苏州南部电网中存在的直流小方式下供电能力受限、无功支撑不足、直流换相失败风险大及直流双极闭锁后应急拉限电多等问题，同时较常规解决措施具有较好的经济性和较小的实施难度。苏州南部UPFC工程对在更高电压等级上应用UPFC技术能起到积极的示范作用。

Application of 500 kV UPFC in Suzhou Southern Power Grid

An introduction is made in this paper to a 500 kV unified power flow controller (UPFC) demonstration project, which is implemented in Suzhou southern power grid and is scheduled to be put into operation by the end of 2017. The UPFC project will be of the largest power capacity and the highest AC voltage level of all UPFC projects in the world. The overview of the Suzhou southern power grid and its existing problems are firstly introduced, and the difficulties for implementing conventional solutions (e.g. upgrading existing transmission lines and constructing new transmission lines) are also addressed. Then, the UPFC solution are discussed, including the project scheme, the effectiveness of the solution, the implementation difficulties and the investment cost. Finally, the economic and social benefits of the 500 kV UPFC project are demonstrated though technical and economic comparisons. The analysis shows that the UPFC project, which has smaller implementation difficulties and better economic benefits than conventional solutions, can effectively alleviate the operation problems of the Suzhou southern power grid, such as limited power supply capacity, insufficient reactive power support, and high risk of commutation failures. The project is of demonstration value to the application of UPFC in higher voltage projects.