基于平滑阈值函数的分布式光纤雷击定位方法

分布式光纤线路经常暴露在复杂的地形条件下,长时间经受雷击等自然因素的侵害。光纤信号传输过程中伴随着扰动信号以及噪声干扰,不能准确监测到输电线路的实际运行状态,进行故障准确定位。针对分布式光纤网络雷击定位准确度不高的问题,构造了一个新的平滑阈值函数。该阈值函数整体平滑连续可导,提高了去噪后信号的质量。通过该函数对输电线路监测的温度信号进行小波去噪,得出线路的沿线分布准确温度值并对故障位置进行精准定位。仿真结果表明,平滑阈值函数相比于传统阈值函数,可以获取更优良的去噪效果,提高了传输信号的信噪比,降低了均方根误差。改善现有电力系统网络雷击故障定位检测精度的不足,提高排除线路雷击故障的精确度,减少故障定位所需的时间。

Improved Wavelet Threshold De-noising Method for Distributed Optical Fiber Lightning Location

Distributed optical fiber lines are often exposed to complex terrain conditions and suffer from natural factors such as lightning strike for a long time. In the process of optical fiber signal transmission, with disturbance signal and noise interference, the actual operation state of transmission line cannot be accurately monitored and the fault cannot be accurately located. Aiming at the low accuracy of lightning location in distributed optical network, a new smoothing threshold function is constructed. The threshold function is smooth, continuous and differentiable, which improves the quality of the de manic signal. Through this function, the temperature signal of transmission line monitoring is de-noised by wavelet, the accurate temperature value along the line is obtained, and the fault location is located accurately. The simulation results show that, compared with the traditional threshold function, the smooth threshold function can obtain better de-noising effect, improve the signal-to-noise ratio of the transmission signal, and reduce the root mean square error. The method can improve the detection accuracy of lightning fault location, improve the accuracy of lightning fault removal line and reduce the time of fault location.