Modelling space charge in the coaxial extruded insulation

In this paper, a bipolar charge transport model was applied to simulate the space charge behaviour within the HVDC cable polymeric insulation. Based on many experimental observations, a threshold electric field at which the charge injection takes place was introduced to the model. Considering the practical operation of HVDC cables, a transient temperature distribution across the insulation was implemented to compute the charge generation and transportation processes. The simulations results suggest that the thermal transient has a significant effect on charge dynamics in the cable