Nonlinear electric conduction of CCTO/EPDM composites used for reinforced insulation in cable accessory

Nonlinear electric conductance of reinforced insulation can homogenize field distribution and suppress local distortion inside high-voltage direct current cable accessories. To achieve a significant nonlinear in ethylene–propylene–diene misch–polymere (EPDM) used for accessories, the inorganic micron crystal powder calcium copper titanate (CCTO) is synthesized by sol–gel method, which filled into EPDM to prepare 5∼15 wt% CCTO/EPDM composites melting blend hot-press molding methods. Microscopic structure, conductivity, (DC) dielectric breakdown strength, charge trap characteristics are tested reveal underlying derivation conduction nonlinearity. Scanning electron microscopy X-ray diffraction (XRD) demonstrate that CCTO fillers uniformly dispersed matrix. Dielectric strength gradually decreases with increase content while persisting qualified electrical DC macron introduce shallower traps than intrinsic derived from structural defect matrix, initiates percolating conductive channels between under high fields, accounting nonlinearity profile density versus strength. Finite-element simulations analyses on electrostatic terminals prove employing 15 composite as efficiently at interface main accessory power cables, great interest develop materials accessories severe environments.