基于SIFT算法与Duffing振子的小电流接地选线

Small Current Based on Duffing Oscillator and SIFT Algorithm Grounding Line Selection

对于小电流系统在发生单相接地故障时,提出一种基于Duffing振子信号检测技术与SIFT算法相结合的单相接地故障选线方法。由于受到高阻接地限制,传统的注入信号法有一定的局限性。Duffing振子系统对信号具有非常高的敏感度,当系统的驱动力不同时,相图的轨迹也是不相同的,通过SIFT算法比较相图相似度,根据相似度大小作为选线判据。不受高阻接地限制,简化了选线过程,抗噪性能好,提高了选线的灵敏度。先通过电压互感器向故障系统相注入信号,然后通过探测器和滤波处理系统提取注入系统中的信号,将提取的信号输入到Duffing系统,通过系统相图相似度的大小准确判断出故障线路。

In this paper,a method of single phase grounding fault line selection based on Duffing oscillator signal detection technique and SIFT algorithm is proposed for small current system in the event of a single phase to ground fault. Due to the high resistance grounding limit,the traditional injection method has some limitations. Duffing oscillator system has a very high sensitivity to the signal. When the driving force of the system does not at the same time,the trajectory of the phase diagram is different,and the phase diagram is compared with the SIFT algorithm. This method is not restricted by high resistance grounding,and simplifies the process of selecting the line,good noise immunity,and improves the sensitivity of the line. Firstly,the signal is injected into the fault system by the voltage transformer. Then the signal is extracted from the injection system by the detector and filter processing system. The signal input to the Duffing system can be determined by the size of the phase diagram of the system.