After the lightning flashover in parallel gaps,the insulator can be protected while the arc being dredged quickly,but it cannot effectively cut off the subsequent power frequency follow current.Therefore,based on the concept of"gas blowing arc",a kind of gas-blowing arc device is designed for HV transmission lines.The device is installed in parallel with the insulator string,and when lightning strikes the line,the gap uses insulation coordination to discharge lightning current into the ground before the insulator breakdown and flashover,and at the same time,with the usage of lightning pulse signal,the arc extinguishing gas pill is triggered to generate high-speed airflow.In this way,the arc can be extinguished before the work of relay protection device.Under ideal conditions,the simulations show that the device can extinguish 20 kA power frequency follow current within 4 ms,and the experiments show that the device can extinguish 5.1 kA power frequency follow current arc within 2.6 ms.The results of simulations and experiments are basically consistent,which jointly verify that the air-blowing arc device has good arc extinguishing effect.
parallel gappower frequency follow currentinsulation coordinationlightning pulse signalarc extinguishing gas pillrelay protection device
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