Electric Field Analysis of Water Drop Corona

Water drops on surface of polymer insulation materials may cause corona because they can enhance the electric field nearby. Water drop corona plays an important negative role in the long-term performance of composite insulators. In this paper, based on a model with two parallel electrodes water drop corona is studied. The relationship between initial corona voltage and different sets of water drops is obtained from experiments. Then several factors, which may affect the electric field analysis of water drop corona, are studied by numerical calculation on computer. Calculation is mainly on a 2-D model. However, a 3-D model is also used to study the effect of water drops distributed in space.