Research on Cable Fault Monitoring and Diagnosis System Based on Daubechies Wavelet Transform

Because of the inconspicuous current distortion of fault sheath of long-distance transmission cables, accurate fault prediction and location are difficult for online cable fault monitoring and locating. Thus, based on wavelet transform, a sheath current method is proposed. Firstly, a cable fault simulation model is established according to the principle of cross-connection. Secondly, the feasibility of using the sheath current method is analyzed to realize fault identification. For the high-resistance faults that cannot be effectively identified by the sheath current method, wavelet analysis is used to extract the fault wave head data and obtain the fault location. PSCAD and MATLAB software are used to carry out simulation experiments. The method is effective in diagnosing various faults such as low-resistance faults, high-resistance faults, and insulation faults of cables, and can achieve precise positioning of cables.