Quality assessment of 110kV three-phase XLPE cables based on cable surface magnetic field distribution characteristics

110kV cross-linked polyethylene cables are increasingly used in distribution networks, but thermal, mechanical and electrical factors can trigger cable insulation degradation during operation. In order to improve the reliability of power cable condition assessment, this paper proposes a cable insulation degradation assessment method based on the characterisation of magnetic induction intensity distribution. Based on the established 110kV three-phase cross-linked polyethylene cable simulation calculation model, the cable magnetic field distribution characteristics are analysed in the case of main insulation air gaps, iron impurities and copper impurities, and the relationship between the defect type, size, location and degree of degradation and magnetic field strength and magnetic field aberration characteristics is established, and the magnetic field aberration characteristics are used to detect cable faults, which improves the effectiveness and accuracy of cable fault detection.