基于小波变换模极大值的输电线路单端故障定位

Non-communication fault locating of transmission line based on wavelet modulus maxima

基于故障行波的输电线路单端故障定位利用故障点的反射行波与入射行波到达母线的时间差计算故障距离,但如何区分来自故障点和对端母线的反射行波仍是一个难题。在分析故障点和母线的反射特性的基础上,利用电流行波线模分量小波变换的最初2个模极大值之间的相对极性区分来自故障点和对端母线的反射行波,并提出了一种改进的基于小波变换模极大值的输电线路单端故障快速定位方法,能够不受故障类型、故障电阻及耦合线路的影响。理论分析和仿真结果表明,该方法切实可行。

The fault distance is calculated based on the interval between the incident traveling wave and the reflected traveling wave from the fault point in one terminal fault locating. However,it is difficult to distinguish between reflected traveling waves from the fault point and from the remote bus. The reflection characteristics of fault point and buses are analyzed,and the reflected traveling waves from the fault point and from the remote bus are identified by comparing the polarities of their wavelet transform modulus maxima. An improved scheme based on wavelet transform modulus maxima for the fast one terminal fault locating of transmission lines is presented,which is independent of the fault type,fault impedance and mutual coupling effect. Theoretic analysis and simulations prove that the scheme is correct and effective.