According to characteristics of EHV transmission line fault transient current,a fault can be identified as internal or external one based on the spectrum energies in many frequency bands.

• 介绍了高压输电线路及母线对高频暂态电流衰减的特点,通过利用多个频带内暂态信号的谱能量来实现区内外故障的准确识别。