直流电场下涂层对导线表面水滴电致运动及电晕放电的影响

Corona discharge phenomenon on overhead transmission lines is usually caused by conductor surface projections, such as raindrops, dirt, etc., of which raindrops produce the most common corona discharge phenomenon. At present, the research on the corona discharge mechanism of DC transmission lines is still not deep or enough in the world, thus, corona discharge has also become one of the problems to be solved for the development of high voltage DC transmission. In this paper, the ball-plate test platform was adopted to study the influences of coating of the aluminium ball in the surface layer attached to the water droplets on the DC corona characteristics, and the the droplets electroluminescent movement characteristics of aluminium surface were also investigated. The simulation software was adopted to establish the droplets electroluminescent movement of the multiphase flow model, and the coating contact angle and the droplet movement morphology on the droplets around the field strength distribution of the impact are analyzed. The results show that the droplet radius decreases with the increase of contact angle, and the droplet length increases and then decreases with the increase of contact angle; the droplet adsorption effect on the surface of the superhydrophilic coating is stronger, the motion amplitude of the droplet is greatly reduced, and the distortion degree of the electric field strength around the droplet is small; meanwhile, the RMS value of the corona current pulse is the lowest; it is difficult for the droplet to exist steadily on the surface of the superhydrophobic coating, and the distortion degree of field strength around the droplet is larger, which is very likely to occur under the electric field effect. Under the action of electric field, jetting phenomenon is very easy to occur, and the degree of distortion of field strength will be reduced after jetting of water droplets.