In recent years, buffer layer failures have been frequently reported in cable systems, which has attracted much attention of both academia and industry. The studies of early researchers mainly focused on analysis of corrosion products in buffer layer failure, buffer layer simulation and detection methods. In this paper, the electrochemical hydrogen evolution corrosion was carried out with the experiments of sheet samples in the laboratory, and the electrical parameters of the buffer layer were measured. In such processes, we observed that the SAP (Super Absorbent Polymer) powder released absorbed water and the water condensed on the glass wall. We explain the characteristics of water release and ablation of buffer layer after electrochemical reaction, and simulate the failure process based on equivalent circuit model. This work provide a reference for the design of water-proof structures in high voltage applications.

corrosion,buffer layer,cable,hydrogen