Effect of Conductor Current on Space Charge Accumulation in HVDC Cable Insulation

Space charge behavior and its understanding in a cable is essential to ensure the reliability of its insulation. A cable under operation experiences a thermal stress associated with the Joule's heating effect because of current in the conductor, which hitherto gives rise to a temperature gradient in the cable insulation domain. In this paper, space charge behavior associated with the temperature gradient has been simulated and temporal studies have been carried out. The modelling is performed using finite element method (FEM). Effect of conductor current on space charge density at different time instances along with interesting observations with temperature variation is presented. Further, space charge accumulation dependency on electric field has been reported.