新一代高性能柔性直流背靠背技术及工程应用

目的  广东电网区域由于负荷密集，网架结构复杂，电气联系紧密，长期存在大面积停电风险、交直流相互影响、短路电流超标三大问题，难以满足未来电源负荷发展和系统灵活调控的需求。 方法  为解决上述问题，在广东电网核心区域建设高性能柔性直流背靠背工程，研究并采用新一代高性能柔性直流背靠背技术。在复杂电网柔性直流互联控制，高可靠、高性能换流阀研发，绿色高效换流站设计等方面开展了深入研究，实现了柔性直流背靠背技术升级。 结果  工程成功实现了异同步潮流自动控制，大幅降低了控制保护系统链路延时，研制出了高性能、高可靠性柔性直流换流阀，并在换流站降噪、降损、节水等方面做了优化设计，建成换流站全景感知系统，实现了智慧运维。目前该工程运行良好。 结论  广东电网直流背靠背工程解决了多直流馈入受端电网长期以来面临的三大稳定问题，增强了粤港澳大湾区电力长期安全可靠供应能力。

New Generation High-Performance VSC-HVDC Back-to-Back Technology and Application in Project

Introduction Due to the dense load, complex grid structure, and close electrical connections in the Guangdong power grid area, there are three major problems for a long time: the risk of large-scale power outages, the interaction between AC and DC, and the excessive short-circuit current, making it difficult to meet the needs of future power load development and flexible system regulation. Method To address the above issues, a high-performance VSC-HVDC (Voltage Source Converter-based High Voltage Direct Current) back-to-back project was constructed in the core area of Guangdong Power Grid, and a new generation of high-performance VSC-HVDC back-to-back technology was studied and adopted. The VSC-HVDC interconnection control of complex power grids, the development of highly reliable and high-performance converter valves, and the design of green and efficient converter stations were deeply studied. The upgrade of VSC-HVDC back-to-back technology was achieved. Result The project successfully achieved automatic control of asynchronous power flow, significantly reducing the link delay of the control and protection system, developed high-performance and highly reliable VSC-HVDC converter valves, and optimized the design in terms of noise reduction, loss reduction, water conservation, and other aspects of the converter station. A comprehensive perception system for the converter station was built, achieving intelligent operation and maintenance. At present, the project is running well. Conclusion The VSC-HVDC back-to-back project of Guangdong Power Grid has solved the three major stability problems faced by the multi DC feeder receiving end grid for a long time and enhanced the long-term safe and reliable power supply capacity of the Guangdong-Hong Kong-Macao Greater Bay Area.