特高压交流对四川电网多送出直流输电系统影响评估

摘要

After the Ya'an-Jingmen 1000 kV UHVAC is put into operation, there will be a world wide unique UHV AC/DC hybrid transmission system in Sicluan power grid. To assess the impact of UHVAC operation on multi-send HVDC system of Sichuan power grid, this paper, based on 2012 high water level and peak load operation mode of Sichuan power grid, uses evaluation indicators like multi-infeed interaction factor and multi-infeed operating short-circuit ratio, and through small disturbance stability analysis and simulation, to compare two running modes which are putting Ya'an-Jingmen 1000 kV UHVAC into operation and not putting it into operation. The results show that UHVAC operation can effectively increase the sending end AC system strength, decrease the interaction among sending-end converter stations, improve small disturbance stability, increase the level of short circuit current and reduce the level of transient overvoltage of three HVDC systems of Sichuan power grid.%雅安-荆门1000 kV特高压交流投运后,四川电网将形成全世界独有的特高压交直流混联输电系统.为评估特高压交流投运对四川电网多送出直流输电系统的影响,针对四川电网2012年丰大运行方式,利用多馈入交互作用因子、多馈入运行短路比等评估指标,通过小干扰稳定性分析和仿真分析,对雅安-荆门1000 kV特高压交流投运和未投运两种运行方式进行对比.结果均表明特高压投运后能有效提高四川电网三条直流系统的送端交流系统强度,减小送端换流站之间的交互作用,提高系统小干扰稳定性,提高短路电流水平和降低暂态过电压水平.