Space charge behavior in polypropylene/polyolefin elastomer/MgO nanocomposites under temperature gradient

Temperature gradient across HVDC cable insulation, which occurs when the cable is under operation, would affect the charge injection and migration behavior and cause space charge accumulation. The space charge accumulation would lead to severe electric field distortion and decreased lifetime of the HVDC cables. So, it is of great importance to investigate the space charge behavior under temperature gradient of HVDC cable insulation materials. This paper aims to investigate the space charge behavior under temperature gradient of the newly developed recyclable HVDC cable insulation material polypropylene/polyolefin elastomer/MgO (PP/POE/MgO) nanocomposites. The results show that space charge accumulation under temperature gradient in PP/POE matrix is severe than that of under room temperature. Introduction of surface modified MgO nanoparticles can both effectively suppress space charge accumulation under temperature gradient and room temperature but the optimal content of MgO nanoparticle varies.