在分析电网故障行波传输特性的基础上提出了一种基于整个电网行波时差的故障定位方法。该方法在整个输电网中的部分变电站安装行波定位装置，线路故障后各行波定位装置检测并记录初始行波的到达时间，由主站根据整个网络中所有初始行波到达时间和线路长度来辨别有效行波时间，并根据所有有效行波时间来进行综合故障定位。与基于单条线路故障信息的行波定位不同，该方法在故障线路端定位装置故障、启动失灵或记录错误时间后仍能可靠定位。理论分析和仿真结果表明，该方法可以在使用较少的行波定位装置的情况下对电网中所有输电线路进行可靠、准确的故障定位，有助于进一步提高行波故障定位的可靠性和经济性。

Based on analysis of propagation characteristics of fault traveling wave in power grid, a power line fault location scheme based on traveling wave time difference in power grid was proposed. Only several substations in the power grid are necessarily being selected to install fault location equipment. When fault occurs on one line, all location equipment record the arrival instant times of initial traveling waves. Thereafter the location master station can distinguish the effective arrival times based on all initial traveling wave arrival times and the length of lines, and locate the fault precisely based on all the effective traveling wave arrival times. Unlike earlier schemes based on the fault information from only one line, its accuracy is not affected when one individual or more location equipment break down, fail in startup, or record wrong arrival time of initial traveling wave. Both theoretical analysis and simulation results indicate that a reliable and accurate location result can be obtained to all lines, even if there are only several location equipment in power grid. The proposed method is helpful to improve the reliability and economy of traveling wave fault location systems.

国家自然科学基金项目(50577001)；教育部新世纪优秀人才计划项目(NECT-04-0781)；湖南省教育厅科技项目(07C088)。