中文摘要：

电网地磁感应电流影响因素多、情况复杂,考虑各电压等级电网的参数特点,以往的GIC地磁感应电流计算集中在电网最高电压等级线路.交流特高压电网建设使我国电网增加了1 000 kV电压等级,综合考虑线路参数、变压器类型等GIC影响因素,准确计算包括500 kV超高压及1 000 kV特高压的多电压等级电网的GIC是重要研究课题.根据我国500 kV和1 000 kV实际电网的参数,并考虑线路走向等因素的影响,假设了一个特高压多电压等级电网,并建立了其GIC全节点模型.计算了两种感应地电场情况下500 kV电网、1 000 kV电网、500 kV和l 000 kV双电压等级电网的GIC,比较了三种情况电网的GIC计算结果.研究了不同电压等级电网GIC的相互作用及电网结构的影响.结果表明,1 000 kV电网GIC与500 kV电网GIC相互影响明显,在特高压电网GIC计算中,既不能在计算最高电压等级电网GIC时忽略次级高压电网的影响,也不能忽略对次级高压电网GIC的治理.

英文摘要：

The factors affecting geomagnetically induced currents （GIC） in power systems are various and com- plicated, considering the parameter characteristics of each voltage level power system, the preceding study mainly concentrated on calculating GIC in the highest voltage-level system. With the construction of UHVAC power grid, the 1 000 kV network is added in the China＇s power system. Taking the length and unit resistance of transmission line and other factors affecting GIC into consideration comprehensively, it is significant to accurately calculate the GIC in multiple voltage level power system containing 500 kV （EHV） and 1 000 kV （UHV） networks. Based on parameters of 500 kV and 1 000 kV real power system, and considering influencing factors such as direction of transmission lines, a hypothetical UHV power grid was presented that was multiple voltage level power system and established its GIC ＂Full-node＂ model, calculated GIC in 500 kV grid, 1 000 kV grid and a dual voltage-level grid considering both 1 000 kV and riO0 kV under two geoelectric field scenarios, then compared GIC calculation results of these three girds, researched on the interaction among GIC in different voltage level power systems and the influ- ence of grid structure on GIC. The results show that the mutual influence between GIC in 500 kV network and GIC in 1 000 kV network is obvious, which means that, during the GIC calculation of UHV power system, should be neither ignore influence of the secondal7 voltage-level system .in calculation of GIC in the highest voltage-level sys- tem, nor ignore the government of GIC in the secondary voltage-level system.