STUDY ON LIGHTNING IMPULSE CHARACTERISTIC OF 220KV COMPOSITE INSULATOR AND PARALLEL GAP DEVICES AT HIGH ALTITUDE AREA

摘要

Lightning impulse experiments on 220 kV composite insulator and its parallel gap devices with different distances under standard lightning impulse were carried out at the high altitude area of 2000 m while their voltage-time (v-t) Characteristic investigated. The v-t curves, drawn by the experimental data, demonstrate that all the v-t curves with the implement of the parallel gap devices are lower than that of the standard 220 kV composite insulator. Based on the insulation coordination principle, this paper recommends the maximum protective distance of the parallel gap device at the high altitude area of 2000 m. Moreover, the flashover records indicate that the parallel gap device drives the arc far away from the insulator and fixes the position of the burning arc.