Abstract:
As an important part of high voltage cable, semi-conductive shielding layer plays a role of uniforming electric field in cable. At present, high voltage cable manufacturing technology is developing rapidly, but high voltage grade cable materials are heavily dependent on imports, there exists many technical barriers. In this paper, the research progress of high voltage cable shielding materials was reviewed from three aspects: development history and key problems, composition and key performance parameters, performance improvement and modification of shielding materials. Firstly, the development history of semi-conductive shielding materials was sorted out, and the main technical bottlenecks and key problems were extracted. Secondly, the conductive and thermal conductivity mechanism of shielding material was discussed, the composition and performance of shielding material were analyzed from three aspects of matrix resin, conductive filler and additive, and the key performance parameters and technical requirements of shielding material with different voltage levels were analyzed. Finally, the formula of semi-conductive shielding layer, the interface characteristics and the influence of the performance of semi-conductive shielding layer on the charge accumulation characteristics of insulation layer were discussed. The new methods to suppress the charge accumulation of HVDC cable insulation layer by modifying semi-conductive layer were proposed. This work can provide theoretical reference for the research and development of semi-conductive shielding materials and performance evaluation of high-voltage cables.