Experimental study using design of experiment of pollution layer effect on insulator performance taking into account the presence of dry bands

Performance of outdoor insulator under polluted conditions depends specially in the contamination layer configuration and conductivity, which makes important to take them into account during the conception and the design of new insulator. This paper presents an experimental study of the flashover voltage of polluted insulator as a function of pollution layer parameters such as; conductivity, layer length, position, number and width of dry bands. Many configurations of pollution distribution are studied using design of experiment methodology. Parameters effects and their interactions have been investigated and evaluated using ANOVA variance analysis statistical technique. The relationship between pollution parameters and the flashover voltage are modeled and analyzed using response surface methodology. Results show how much the flashover voltage of non-uniformly polluted surface is mainly influenced by length of contamination layer and conductivity. Moreover, the obtained statistical models of flashover voltage are adequate with experimentation results. Such information can be exploited to optimize the design of glass insulator used in polluted areas, by making suitable design to create much and wider dry bands in the middle of the insulator surface.