The gas gap switch used in the fast bypass operation of the distribution network has obvious advantages

simple structure and low cost; however

the working coefficient in the operation process is difficult to adjust quickly due to the determination of the trigger condition parameters. At present

there is a lack of research on the influence of the trigger condition parameters on the trigger performance of the gas switch under constant low working coefficient. This paper builds a research platform for the triggering characteristics of gas switch jet plasma under a constant low working coefficient. The results show that

under the constant low working coefficient

when changing the content of the gas medium component

there is a significant difference between the evolution morphology of the gas gap switch jet plasma and its characteristic parameters (axial height

radial diameter)

and the contact delay does not change significantly. The increase of the pressure hinders the development of the plasma jet

which causes the axial height of the jet plasma to decrease

resulting in the increase of the contact time delay of the gas switch and the increase of the critical working coefficient. Compared with N2 and mixed gas of N2 and SF6

the axial height of plasma jet in SF6 decreases greatly with the increase of gas pressure

and the increase of switching delay and critical working coefficient is obvious. When the main gap distance is changed

the main gap induced breakdown process of the gas switch is different

and the change of the switching time delay and the plasma ejection characteristic quantity is more significant; meanwhile

the critical working coefficient increases with the increase of the distance. With the increase of the trigger voltage

the electric power of the arc channel of the trigger chamber increases

the energy deposition efficiency of the arc channel decreases

the plasma jet height increases

the contact capacity of the gas switch increases

and the critical working coefficient and the contact delay are significantly reduced. The research results can provide theoretical guidance for the performance optimization and engineering application of gas gap switches.