Effect of Carbon Black Structure on Charge Accumulation at the Interface between Insulation and Shielding for Thermoplastic Polyethylene Cable

LLDPE and HDPE blended non-crosslinked insulation materials are considered promising as new environmentally friendly cable insulation materials, due to excellent electrical and mechanical properties. It is necessary to simultaneously develop non-crosslinked semi-conductive shielding materials that match LLDPE/HDPE blends. In this paper, thermoplastic LLDPE/HDPE blend insulation materials and LLDPE/CB semi-conductive composite were prepared. The space charge distribution in the insulation layer under different electric field strengths and times was tested using the pulsed electroacoustic method. The influence of CB structure on charge accumulation at the interface was investigated. The results suggest that adding a small amount of small particle CB can effectively reduce the accumulation of space charge and suppress electric field distortion in the insulation under high electric fields. However, adding excessive small CB black can increase the electric field distortion under high electric fields.