基于VMD和柔性形态学的输电线路故障测距方法

针对输电线路故障测距和信号中存在噪声干扰的问题,提出了基于VMD和柔性形态学去噪技术的输电线路故障测距方法。首先利用变分模态分解(Variational Modal Decomposition,VMD)对信号进行分解,在分解过程中自适应的去除一部分噪声;然后,通过平均柔性形态学滤波器进一步的去除残余干扰;最后使用柔性形态边缘检测有效放大信号奇异点,再设定输出阈值减少噪声背景对信号突变点的影响,可以很清晰的得到故障发生时刻。实验表明此方法有很好的噪声鲁棒性,在抑制了噪声干扰的同时放大了行波特征信号,能够有效检测输电线路故障行波波头,获得更高的检测精度。

Transmission line fault location method based on VMD and flexible morphology

Aiming at the problem of fault location and signal interference in transmission line,a fault location method of transmission line combining VMD (variational modal decomposition) with soft mathematical morphology was put forward in this paper.Firstly,VMD is used to decompose noisy signals,and a part of noise is automatically filtered out in the decomposition process.Then,the residual interference is further removed by the average flexible morphological filter.Finally,the flexible shape edge detection is used to amplify the singular point of the signal,and then,the output threshold is set to reduce the influence of the noise background on the abrupt change of the signal.The experimental results show that the proposed method has good noise robustness,and can suppressthe noise interference and amplify the traveling wave characteristic signal.It can detect the fault line of the transmission line effectively and obtain higher detection accuracy.