Numerical Simulation on Suppression of Space Charge Accumulation by Deep Trap Coating at Electrode-Polymer Interface

Space charge accumulation under DC electric field leads to accelerated aging of insulation, and nano-doping can effectively suppress space charge accumulation, but it is difficult to achieve uniform doping of nano-fillers in engineering. In this paper, a bipolar space charge transport model considering the interfacial layer is developed to investigate the effect of interfacial coating and its trap parameters on space charge. The results show that the construction of deep trap coating on the polymer surface can effectively suppress space charge accumulation, and the increase of coating capture coefficient, trap density and trap depth is beneficial to the coating to capture more charge, suppress charge migration into the polymer and reduce the degree of electric field distortion.