Critical Trigger Conduction Characteristics and Influence Law of Induced Trigger Gas Gap Switch

With the development of smart distribution networks, the demand for switching equipment is gradually increasing. Jet plasma-induced trigger gas gap switch has become a major concern in the direction of new energy and power equipment. In order to study the influence of the change in physical parameters caused by plasma jet on the gap conduction in gas gap switch, the phenomenon of plasma jet-induced gap conduction discharge is analyzed in this article. Considering the plasma jet characteristics under different gap distances and the changes in physical parameters, a simulation model of jet plasma-induced breakdown is built, and the gas gap switch trigger conduction test is carried out to verify the simulation results. Simulation results reveal that the plasma jet generates a pronounced low-pressure region at the jet head, where the pressure drops far below the ambient level at the conduction moment. As the gap distance increases, the formation time of the low-pressure region is delayed, accompanied by reduced streamer propagation speed and prolonged conduction delay. Trigger conduction experiments are further conducted to validate the simulation results, showing good agreement in plasma jet development characteristics and conduction time. The results demonstrate that the minimum pressure induced by the plasma jet is the dominant physical factor governing streamer initiation and critical conduction in gas gap switches. The research results can provide a reference for the critical conduction law of gas gap switch.