Analysis of electric field distribution on the surface of polymer post insulator used in electric railway catenary system

In order to check the electric field distribution of polymer line post insulator, we performed electric field simulation according to state of water droplets. Water droplets use sea water contaminant. The water droplets may appear in different forms and sizes, therefore the form is defined by the angle shape between the surface of the water droplet. The water droplet may measure from less than 90 degree (hydrophilic) up to greater than 90 degree (hydrophobic), depending on the properties of insulator surface. This paper describes numerical analysis calculation of electric fields and its potential distribution in the surrounding of water droplets on an insulator surface. Electric field analysis is performed with change of contact angle, number and distance between water droplets. The computation results show that the electric field close to the water droplets tends to be higher as number of water droplets increases. The electric field fluxes were also affected slightly by the contact angle.