High-Voltage Cable Fault Detection Technology Based on Broadband Impedance Spectroscopy

Aiming at the difficulty of fault detection of high-voltage single-core cables, a new method of cable fault detection based on broadband impedance spectroscopy is studied. Firstly, the relationship between the wave impedance and the distributed parameters is deduced from the distributed parameter model theory of the cable, so as to obtain the key factors affecting the impedance. Then, the broadband impedance spectroscopy of the cable is measured by the linear resonance technique, and the characteristic data is analyzed and extracted from the impedance spectroscopy to obtain the relevant unknowns of the fault defect, so as to realize the cable fault detection. A 220kV cable fault is detected, and the analysis results show that the broadband impedance spectroscopy analysis can detect the cable insulation defects, and the fault location accuracy meets the engineering requirements. The given method can provide a technical reference for fault detection of transmission cables.