Research On Fault Analysis And Diagnostic Techniques Of Power Cable

With the development of the industrialization and the reform of distribution network, cables gradually replace the overhead lines to be widely applied. To ensure the security and reliability of power transmission lines, the power supply system failures caused by cable faults and the unnecessary loss should be avoided. Consequently, it’s significant to analyse, diagnose and locate on the cable faults. Also, it’s the key link to guarantee the safe and steady operation of power transmission line and promote the reliability of power supply.The production mechanism and classification of cable fault are introduced in this paper. The causation and characters of cable fault are summarised. With the help of fault tree, cable fault is qualitative analysed. The evaluation and prediction of the fault are taken place using the FMECA analytical method. The influence of the different parameters is given, such as fault mode, extent of injury and so on. The relevant measures are concluded to avoid the cable fault.The characters of different neutral grounding models in10kV distribution networks are analysed and compared. Based on the ATP-EMTP simulation platform, the system modeling and simulation are undertaken which is grounded via low resistance through neurtral point. The essential characters of cable faults and the impacts of different fault factors on cable faults are discussed.To realize the accurate identification and location of cable faults, the combination of wavelet analysis and neural network is adopted as the fault diagnosis method. Wavelet packet decomposition is used for feature extraction of cable fault signals which are input vectors after normalization processing. RBF network structure is built and relevant practice and test of cable fault diagnosis are conducted, so that the detection of cable faults can be effectively achieved.