基于信号穿透的电力接地网状态检测方法

A Detection Method for Electric Power Grounding Grid Based on Signal Penetration

接地网是保障电力系统安全运行的重要部分,其隐蔽的敷设位置造成检测的局限性,探求便捷高效的检测方法具有重要意义。针对接地网检测的特点,研究基于雷达信号穿透的无开挖检测方法,利用适当的雷达波形穿过土壤介质以携带接地导体的物理信息。设计有效的穿透波形,利用随机信号提高检测系统的抗干扰性,采用类钟型功率谱以保证足够的输出分辨率,增大随机信号的方差以提高波形的穿透性,模糊函数验证所设计波形满足检测要求。此外,通过试验接地网检测验证所提方法的有效性,能够准确地检测到各接地导体的基本物理状态,分辨率与检测深度均与接地场景一致。

Grounding grid is an important part of ensuring the safe operation of the power system, whose hidden laying place causes many limitations to the detection. Therefore, it is of great importance to explore a convenient and efficient detection method. According to the characteristics of the grounding grid detection, a new detection method without excavation is studied based on the radar signal penetration, where the physical information of the grounding conductor is carried by choosing appropriate radar waveform and let it through soil medium. An effective penetrating waveform is designed, which uses random signal to improve the anti-interference, and utilizes bell-like power spectrum to ensure adequate output resolution and increases the variance of the random signal to improve the penetration of the waveform. The designed waveform meets the detection requirements and it is verified by the ambiguity function. In addition, the validity of the proposed method is verified by the test of the grounding grid, which can detect the basic physical state of each grounding conductor accurately. Resolution and detection depth are consistent with the grounding scene.