Research on the Effect of an Air-Blown Interrupting Gap to Reduce the Rate of Lightning Tripping

Abstract

The air-blown interrupting gap protection method is a self-energy interrupting method based on the concept of suppressing arc building by frequency continuation. In order to verify the effect of an air-blown interrupting gap to reduce the rate of line lightning tripping, in this paper, the protection principle of the air-blown interrupter gap is first described, and the action process simulated by COMSOL Multiphysics simulation software. Next, a frequency renewal test circuit is built for the test. Then, an arc-building rate calculation model and a lightning trip rate calculation model under the condition of an air-blown interrupting gap are established, and, finally, a 10 kV overhead line in Yunnan is selected for the verification of the calculation example. The results show the following: a gas blowing arc gap can be effectively extinguished in about 2.5 ms frequency arc and with no re-ignition phenomenon. Before and after the installation of the gas blowing arc gap line, the arc rate changed from 37.27% to 4.1%, respectively, and the lightning trip rate changed from 8.64 times/(40 thunderstorm days—100 km) to 0.337 times/(40 thunderstorm days—100 km), respectively. The decline rate was more than 95%, and in actual operation, it reduced the lightning trip rate enough to achieve good results.