Research on Cable Aging and Joint State Detection Technology Under the Effect of Multi-physical Field Coupling

Operating cables will inevitably undergo insulation aging due to the influence of electric field, magnetic field, heat, light, moisture and other factors, and the insulation performance will be significantly reduced. Statistics show that cable joint failure is one of the important causes of cable failure. The multi-physical field coupling model adopts a variety of physical field interfaces such as electric and acoustic coupling to simulate the discharge waveforms and waveform propagation forms generated by cable joint defects. Firstly, the relationship between voltage and insulation fault is established, and the cable insulation fault is diagnosed by the electric field characteristics. In addition, the electric field characteristics are used to reflect the location of charge agglomeration area, and then the discharge signal at this location is detected to diagnose the deterioration degree of insulation materials.