Study on electrical properties of donor ZnO nanoparticles/EPDM composites

Rubber-based composites with outstanding nonlinear electrical conductivity can improve the electric field distribution of cable accessory, which have been widely used in cable accessory and high-voltage engineering. In this paper, a sol–gel method was used to prepare the iron ion doped ZnO nanoparticle inorganic filler, and then it was added to the EPDM rubber to prepare the composite. The microstructure and electrical properties were systematically studied. The results show that with the increase of inorganic fillers content, the nonlinear conductivity becomes much more distinguished, accompanying with the increased conductance nonlinear coefficient and the decreased breakdown field strength. The conductance nonlinear coefficient and breakdown field strength of the donor ZnO nanoparticles/EPDM rubber composites have been improved to a certain degree than that of the ZnO nanoparticles/EPDM composites. In addition, as the temperature increases, the conductance nonlinear coefficient and breakdown field strength decrease simultaneously. Finally, the simulation results also verify that the donor ZnO/EPDM composite with nonlinear electrical conductivity can uniform the electric field distribution of cable accessory, which provides an effective way to protect the safe operation of power transmission system.