Cable Fault Detection Based on Time Domain Reflection Method

This paper focuses on cable fault detection based on Time Domain Reflectometry (TDR). Given that cables are widely used in many fields and are prone to degradation or faults, traditional detection methods have limitations, and TDR has become a focus of research due to its simplicity of implementation and high accuracy. In this paper, the principle of TDR is described in detail, i.e., transmitting a pulsed voltage wave to the cable and locating the fault based on the reflected refracted waveform at the point of wave impedance mismatch, and the formulas for calculating the wave impedance, travelling wave speed and fault location are given. The equations for wave impedance, travelling wave speed and fault location are given. The equivalent distribution parameter model is also described from micro and macro perspectives. The Gaussian pulse signal is collected at different sampling frequencies from 50 MHz to 500 MHz by simulating the fault of 80 m cable at 70.7 m, and the results show that the higher the sampling frequency, the denser the sampling points of the waveform, the more accurate the measurement of wave delay interval, and the higher the fault location accuracy.