基于小波变换的EHV输电线路单端暂态电压保护算法的探讨

讨论了信号李氏指数的小波变换特性,提出了一种基于暂态电压信号小波变换的超高压输电线路单端量保护算法。利用单端暂态电压信号的小波变换模极大值,对电压信号的李氏指数进行最小二乘法估计,以便判断故障线路。仿真表明,在各种故障情况下该保护算法都足以提取和放大故障线路和非故障线路的差异,可靠、准确地动作。

Study of a wavelet transform based one-terminal transient voltage signals protection algorithm for EHV transmission line

Signal Lipschitz exponent based on wavelet transform is introduced, and a one-terminal transient protection algorithm for EHV transmission lines based on wavelet transform of transient voltage is presented. With the wavelet modulus maxima of one-terminal transient voltage, the Lipschitz exponent of transient voltage signals is estimated by using least square method, then the fault line and non-fault line are distinguished. The simulation results prove that the algorithm can extract and amplify the differences between fault line and non-fault line, and it is reliable and accurate.