Simulation Analysis of Flashover Characteristics of 220kV Composite Insulators Based on Finite-Element Method

摘要

In order to enhance the ability to anti-pollution flashover, a new measurement taking composite insulators instead of glass insulators is adopted. In order to grasp the impact of flashover features of lightning striking insulators, the mechanism of insulators discharge, contrast level of composites insulators and glass insulators lightning flashover voltage as well as differences in flashover features of lightning striking , this paper carries on electric field simulation for insulators loaded with positive DC voltage through computer simulation software ,studying the dynamic changes of the electric field, and lightning flashover insulator process is derived by combining with gas-discharge theory . By comparing the field level of different section of the glass and synthetic insulators and variation of field strength with time-variation, the path of the respective insulator flashover is forecasted. And on this basis, establish the circuit model of Arc - air flashover for solving the minimum flashover voltage in the use of differential calculation, Combine with the final test to verify. The results show that the flashover circuit model is built in accordance with the experimental results; Lightning strike flashover performance of composite insulator with ring is better than glass insulators.