Research on 110kV High-Voltage XLPE Cable Ablation Faults Based on the Substance Precipitated from Moisture Waterproof Medium

In recent years, ablation of the waterproof medium in 110kV XLPE cables have occurred. The main manifestation about ablation points is that white powdery substance is precipitated on the surface of the waterproof medium after the cable is damp, causing breakdown of the insulation shielding layer and corrosion of the metal sheath. This article focuses on the formation conditions of substances precipitated on the waterproof medium of the 110kV cable and its influence in the 110kV cable ablation fault. By carrying out the damp simulation test of the waterproof medium sample, the chemical reaction of the precipitate produced the reason for the corrosion of the metal sheath are proposed. By carrying out the damp simulation test of the 110kV XLPE cable sample, the change characteristics of AC resistance and the DC resistance after cable damp are analyzed. The temperature rise model of the contact resistance of the waterproof medium is established, and the influence of the moisture defect of the cable waterproof medium on the operation of the cable is analyzed. The effect of substance precipitated on the water blocking buffer in the ablation fault of the 110kV cable is proposed.