Research and application of a new jet stream arc extinguishing gap lightning protection device

After the lightning flashover, the resulting power frequency arc will burn insulator strings and wires, which can cause the accidents of insulator string burn-out and overhead conductor damaged. To solve the problem,a new kind of jet stream arc extinguishing gap lightning protection device (JSIGLPD) installed in the overhead transmission lines was developed. And it was feasible to adopt scatter type gap lightning protection scheme. The scheme can provide better lightning protection for overhead transmission lines. The JSIGLPD can achieve the function of limiting the external over-voltage on insulators and avoiding frequent tripping of circuit breaker. With high-speed camera and oscilloscope,the process and waveforms of voltage and current changing in arc extinguished test was observed. This paper studied the movement characteristics of electric arc under the conditions of jet stream based on the chain arc model and shock wave theory, and discussed the arc quenching process.