Fast insulation recovery characteristics of induced trigger gas gap switch

Abstract

Gas gap switch has good application prospects in power systems, due to its quick response and simple structure. However, there is still little research on insulation recovery characteristic. Therefore, the double pulse method is used to study the influence of switch gap distance, trigger medium pressure and trigger medium type on the insulation recovery characteristics of gas switch. The experimental results show that the insulation recovery characteristics of induced trigger gas gap switch experience three stages: transition period, fast recovery period and saturation period. The duration of the saturation period is much longer than the sum of the previous two stages, and there was no 'platform phenomenon' in the rapid recovery period. With the decrease of gap distance, the insulation recovery rate of gas switch increases gradually, and the basic recovery time of gap insulation (insulation recovery coefficient RU > 90%) can be reduced by 50%. The influence of trigger medium pressure on the insulation recovery of gas switch is significant, and the influence characteristics on the insulation recovery process are different. Increasing the trigger medium pressure will slow down the insulation recovery process of gas switch. In 0.1~0.3 MPa compressed dry air, the basic recovery time of gas gap switch insulation corresponds to 11~40 ms. The strong electronegative gas SF6 has a significant effect on the insulation recovery rate of gas switches, and its insulation recovery rate is close to 4 times that in air. The research results provide theoretical guidance for the rapid insulation recovery of gas gap switch.

Keywords

• gas gap switch
• induced breakdown
• double pulse method
• insulation recovery characteristics
• gas breakdown voltage
• strong electronegative gas sf6