The effect of installation angle and rain intensity on partial discharge arising on the cap insulator polluted and wet porcelain plate

In the electric power system, especially in transmission lines, plate insulators are assembled into chain insulators to separate the live parts from the non-voltage parts. Insulating materials used variations from porcelain, glass, and composites. Mounting angles used variations, such as suspension or insulator straight hanging and tension to pull the conductor. Over time, the insulator will be exposed to pollutants from the environment. This attached pollutant will facilitate the emergence of partial discharge on the insulator. In addition to pollutants, rainfall will also affect the partial release of the insulator. Based on this problem, the research analyzes the effect of the angle of installation of the chain insulator until partial discharge occurs in dry conditions, polluted conditions, and wet conditions after being given a certain intensity of rain. The results of the analysis of this study concluded that the more horizontal the angle of insulator installation, the lower the voltage supplied to the insulator to cause partial discharge. This occurred in the dry condition insulator and polluted and wet with NaCl pollutant. However, in wet conditions of CaCO3 pollutant, the voltage tends to decrease from 0° to 45° and then rises again at 60° and 90°.