西电东送纯直流输电方案研究

2015年后全国联网格局将逐步形成,届时,全国电网将分为四个同步电网,即东部电网、中部电网、南方电网及西北电网.对于远距离(超过1000km)、大容量(超过50GW)的西电东送工程,如果采用纯直流输电方案,将会出现多条直流线路同时落点于同一交流系统的情况,这对交流系统的安全稳定运行有一定影响.文章以2030年为水平年,分析了在不同直流和交流系统故障情况下各同步电网的稳定性,并对多直流落点系统中各直流线路的恢复特性进行了研究.分析结果表明,西电东送工程采用纯直流输电方案在技术上是可行的.

STUDY ON PURE DC TRANSMISSION SCHEME FOR FUTURE POWER TRANSMISSION FROM WEST CHINA TO EAST CHINA

In the year after 2015, the nation-wide power grid interconnection in China will be formed step by step. At the appointed time, this nation-wide interconnected power grid will be divided into four synchronized power systems, i.e., the East China power grid, the Central China power grid, the South China power grid and the Northwest China power grid. For long distance (longer than 1000km) bulk power (more than 50GW) transmission from West China to East China, if the pure DC transmission scheme is adopted, there will be more and more HVDC links feeding power to different points in a same synchronized AC network, and such situation may affect the secure and stable operation of AC network. Taking the year of 2030 as the target year, the stability of the synchronous power grids under different faults occurred in AC and HVDC systems is analyzed and the recovery characteristics of the DC transmission lines within the multi-infeed HVDC systems are researched. The research results show that pure DC power transmission from West China to East China is technically feasible.