Research on the Influence Mechanism of Thermal Aging Degree of Cable on Frequency Domain Reflectometry and Defect Location Accuracy

Compared with high-voltage transmission cables, 10kV distributed cables are currently receiving less attention. Contrary to the continuously improving national overall power supply reliability, the failure rate of 10kV distribution cables is not optimistic. Thermal aging is an important cause of defects in distributed cables, which further develop into failures. This paper conducts research on defects of different severity, uses FDR to determine the severity of defects, and analyzes the impact of defect development on positioning accuracy. Firstly, we establish a simulation model of the aging cable, and use the windowed Fourier transform to locate the multi-point aging. Then, we carry out relevant experiments based on the simulation results to further verify the accuracy of the algorithm. The simulation and test results show that for cables of the same length, the aging time has no effect on the defect location accuracy. The positioning accuracy of simulation and test algorithms are within 0.46%.