A High-Voltage and High-Current Miniaturized Surface Flashover Triggered Vacuum Switch

To satisfy the small size requirement of high-power closing switch for compact pulsed power system, a miniaturized surface flashover triggered vacuum switch (STVS) with high withstand voltage and high-current is designed in this article. Through optimizing the switch structure, the maximum withstand voltage of the switch is exceeding 35 kV and the maximum conduction current capacity is more than 40 kA under the dimensional parameters of a total height of 39.5 mm and a diameter of 39.5 mm. The experimental test circuit is built, and the conduction delay time characteristics and impedance parameters of the miniaturized STVS are measured under different operating conditions. The experimental results show that the conduction delay time of the miniaturized STVS is significantly reduced with the increase of the trigger current and the operating voltage. The increase in conduction current leads to a decrease in the impedance of the vacuum arc channel, which reduces the resistance and inductance of the miniaturized STVS. The change in trigger current has no effect on the miniaturized STVS impedance parameters. At the operating conditions of 9 A trigger current, 15 kV operating voltage, and 40 kA conduction current, the conduction delay time of the miniaturized STVS is 1048.8 ns, the jitter is 139.7 ns, the resistance at the peak current moment is 51.2 m Omega, and the inductance at the current passing zero moment is 151.9 nH. Moreover, the operating characteristics of the miniaturized STVS have not deteriorated significantly after 200 consecutive operations under this operating conditions.