Surface flashover triggered vacuum switch (STVS) working performance mainly depends on the electrical characteristics of trigger pulse. This article presents an experimental investigation of the trigger process. The influence of the electrical properties of the trigger pulse on the trigger characteristics is focused. Based on the self-developed high-performance STVS product, the experimental test platform was established. The experimental results show that a shorter delay time of STVS can be obtained by heightening trigger voltage. However, the effect of trigger voltage on time jitter is not obvious. The slight increase in trigger current has evident influence on trigger delay time. It also does not affect the stability of trigger delay. With the increase in trigger voltage rise rate, the trigger delay time and time jitter can be optimized. Finally, the long-term stability of STVS is discussed. After 300 trigger times, the delay time changes from about 140 ns to more than 150 ns and the jitter changes from about 5 ns to more than 10 ns. In the design of STVS products, it is recommended to adopt a trigger system with a fast rise rate of trigger voltage and trigger current.

The trigger characteristics of the laser-triggered vacuum switch (LTVS) are significantly affected by the parameters of the laser-produced initial current. In this paper, a low operating voltage is applied across LTVS, and the trigger experiments are carried out under different laser energy and operating voltage. The initial current is obtained by measuring the voltage drop across a 25 Ω resistor. The influence of laser energy and operating voltage on the trigger characteristics can be characterized by the parameters of the initial current, such as the current peak value, the number of charges released, the rate of rise, and the delay time. The experimental results show that an increase in laser energy can increase the current peak value, the number of charges released, and the rate of rise, and can decrease the delay time. These results show that an increase in laser energy helps the LTVS trigger process. The external electric field is much smaller than the laser electric field. Hence, only the current peak value is affected by the operating voltage, and the impact on the other current parameters is weak.

The conduction delay time is one of the main technical parameters of the surface flashover triggered vacuum switch (STVS). Detailed research and optimization of conduction delay time characteristics are necessary for the development of high-performance STVS. In this paper, the conduction performance of STVS with different electrode structures and operating parameters is investigated in detail. Based on the analysis of the conduction process, the factors affecting the STVS conduction delay time are discussed. The experimental platform is built by using a detachable vacuum chamber, and the conduction delay time characteristics of STVS are compared under different electrode structures and operating parameters. This research analyzes and discusses the reasons for the influence of electrode structures and operating parameters on conduction delay time. The experimental results show that the structure with the trigger gap flashover surface parallel to the cathode surface has a better conduction delay time than the structure with both perpendicular to each other. Both reducing the trigger electrode embedment depth and extending the trigger gap flashover surface length can optimize the conduction delay time of STVS. However, increasing the trigger gap flashover surface length only reduces the conduction delay time at the initial stage of STVS operation. The shorter the main gap distance, the smaller the conduction delay time of the STVS. In addition, increasing the trigger current and operating voltage can diminish the conduction delay time of STVS.

Due to the insulation saturation effect of a vacuum gap, the series connection is the main method to improve the capability of the triggered vacuum switch (STVS) to withstand voltage. In this paper, a double-gap surface flashover triggered multistage vacuum switch (DMVS) is constructed based on a removable vacuum chamber. The DMVS consists of a surface flashover triggered vacuum gap (STG) and a self-breakdown vacuum gap (SBG) in series. The trend in DMVS conduction delay time under different operating parameters and gap distances is firstly measured through experiments, and then the conduction delay time characteristics of DMVS and single-gap STVS compared. The test results show that increasing the trigger current and operating voltage and decreasing the gap distance of each vacuum gap can optimize the conduction delay time of the DMVS, but the voltage division ratio between the STG and the SBG has no obvious influence on the conduction delay time. The comparison result between the DMVS and the STVS shows that increasing the number of series gaps increases the conduction delay time but, for a certain vacuum gap distance, DMVS exhibits superior conduction delay time characteristics compared to STVS.