Modulation of anti-corona properties by ZnO nanoparticles and SiO₂ nanoparticles

The stator wire rod end is prone to corona discharge phenomenon due to localized concentration of electric stress, causing insulation failure and reducing the working life of the motor. At present, the effective measure to solve the corona discharge is coating the stator bar end with nonlinear corona paint to realize the material conductivity characteristics and the distortion of the electric field strength of the adaptive matching, which reduces or eliminates the surface of the bar end of the phenomenon of electron accumulation to play the effect of anti-corona. In this paper, SiC/EP, ZnO/SiC/EP, and SiO₂/SiC/EP micro- and nanocomposites were prepared by water bath heat blending method. The effect of ZnO nanoparticles and SiO₂ nanoparticles on the nonlinear conductivity properties, and thus on the corona-proof properties, was investigated. The results show that both surface conductivity and nonlinear coefficient can be enhanced by adding appropriate amounts of nano-ZnO and nano-SiO₂ into SiC/EP composites; the electric field on the surface of the wire rod is the smallest after using 1-ZnO, and the temperature on the surface of the wire rod is the highest after using 1-SiO₂.