Calculation and Study on the influence of insulator surface pollution on its insulation performance

Abstract

The voltage equalizing characteristic of line insulator string is an important electrical performance to be considered in insulator selection and long-term operation. Especially in dusty areas, due to the influence of geographical and natural conditions, bird droppings and dust accumulation are often the problems to be faced in the operation of insulator strings. In this paper, considering the influence of stray capacitance and phase to phase, the simulation calculation model is established for the typical porcelain insulator string and composite insulator string of 500kV line. The electric field calculation and analysis under normal working conditions, bird droppings working conditions and pollution accumulation working conditions are carried out respectively, and the potential, electric field distribution characteristics and insulator voltage sharing characteristics of insulator string under different working conditions are obtained. The effects of bird droppings with different particle sizes and positions on the electric field distribution of insulator strings and the effects of pollution caused by sand and dust settlement on the insulation and long-term operation reliability of insulator strings are revealed. The research conclusion has positive guiding significance for line insulator string operation and maintenance and condition assessment.