柔性直流输电技术的现状及应用前景分析

Flexible HVDC Transmission Technology's Today and Tomorrow

柔性直流输电技术发展至今已经逐步走向成熟,尤其是在欧美地区,已经建成了数十条不同技术路线的柔性直流输电工程,积累了大量的工程经验。而在我国,该技术多年来一直处于理论研究阶段,最近几年才刚刚开始大量兴建示范工程。为给我国柔性直流技术的普及和工程应用提供参考,总结了国内外柔性直流输电的典型工程及技术应用现状。梳理了柔性直流输电的原理、结构和技术特点,系统总结了该技术的演化发展和工程应用经验,分析了柔性直流特有的独立控制有功无功功率,无换相失败问题等优点,提出了受电压源型换流器元件制造水平及其拓扑结构的限制导致柔性直流输送容量小、成本高、故障承受能力较弱等问题。结合我国能源发展战略和电网发展中遇到的问题,对柔性直流输电技术的应用领域以及未来电网的发展方向提出了一些具有积极意义的设想和建议。

The flexible HVDC transmission technology gradually matures currently, especially in the developed countries, where dozens of flexible HVDC projects with different technical routes have been built and a lot of experience in engi- neering is gathered. Meanwhile in China, the technology has been studied for a long time, and a number of demonstration projects are constructed or in construction only from the recent years. Therefore to provide reference for promoting and applying the flexible HVDC technology in China, we summarized some typical engineering projects and the application status of the technology. This work includes reviewing the principle, structure and technical characteristics of HVDC flexible transmission, summarizing the technology＇s and engineering experience, analyzing the technology＇s pros such as the independent control of active and reactive power, commutation failure free, etc., and cons including small capacity, high cost and poor tolerance of faults due to the incapability of manufacturing voltage source converter components and the technology＇s topology constraints. According to China＇s energy development strategy and some problems that we encountered in the power grid development, we presented some ideas and suggestions for the application and development of HVDC flexible transmission technology.