Improving Electrical Distance Accuracy for Cable Fault Location Based on the Prony Method

In recent years, the cable fault detection method centered on the traveling wave method has been widely used. But the method has the problem of large deviation in the electrical distance accuracy of cable fault location due to the aging of cable segments. Therefore, an improving electrical distance accuracy for cable fault location based on the Prony method is proposed, obtaining the wave velocity of different sections of the cable to improve the cable fault electrical distance positioning accuracy. By establishing a frequency-variable coupling model containing the transfer function of the cable with double joint structure, studying the mapping relationship between the cable attenuation constant and the electromagnetic wave velocity, and adopting the Prony estimation method combined with the singular value decomposition noise reduction algorithm to achieve the extraction of the attenuation constant and the decoupling of the segmented wave velocity, thus improving the electrical accuracy of fault location. Finally, the feasibility and effectiveness of the method are verified by simulation and field 680 m/10 kV power cable. Experimental results demonstrate that the method efficiently addresses the issue of significant deviations in electrical distance accuracy for cable fault location, which arise from uneven wave velocity distribution resulting from cable aging.