Experimental Investigations on Trigger Characteristics of Pseudo-spark Switch Based on Surface Flashover Technology

Abstract

A trigger device and a triggered pseudospark switch (TPSS) were designed based on surface flashover technology, in order to meet the requirements from present pulse power technology and pulse current test technology such as a long lifetime, reliability in a wide voltage range, a short delay time, as well as small delay jitters. The trigger devices were made from different dielectric materials, with their permittivities from tens to thousands. The trigger characteristics of TPSS were investigated. The results indicate that the high-dielectric trigger device shows better performance and higher emitted charge of the electron emission within all adjusted parameters including the gas pressure and applied voltage. For the dielectric material with relative permittivity εr of 3460, when the gas pressure is 7 Pa, the hold-off voltage of TPSS is 28 kV, the minimum trigger switch voltage drops to 128 V, the minimum discharging delay time and delay jitter are less than 35ns and 6ns, respectively, and the reliable operation can be reached within a very large range of charging voltage, between 0.46% and 99% of its self-breakdown voltage.

Experimental Study on Triggering Characteristics of a Surface Flashover Triggered Vacuum Switch

“…From the theory of surface flashover trigger, it is shown that the surface flashover device is the key component of TVS, with its trigger characteristics depending mostly on field emission caused by the distortion of the electric field of MVD. The degree of distortion is proportional to the relative dielectric constant of the trigger dielectric material [14,15] .…”

“…In order to solve the problems of poor triggering characteristics and consumption of coating material in the high arc current, different dielectric materials are tested. The experimental results show that the dielectric material with high relative dielectric constant (ε r =2500) exhibits a high charge releasing ability and is suitable for surface flashover triggering devices [14,15] . At the same time, a special structure is designed to restrain high arc current pollution and improve the lifetime of TVS.…”

Experimental Research of ZnO Surface Flashover Trigger Device of Pseudo-Spark Switch

“…Gortler [8] had studied the erosion characteristics of different ceramics, the experimental results showed that CaTiO 3 material exhibits lower erosion rate which can prolong the lifetime of the PSS. Yao et al [9] designed a ZnO semiconductor surface flashover trigger device and the experimental results showed that the ZnO flashover trigger device has excellent electron emission capability. In this paper, the experimental setups of the trigger system are built, the test method for measuring the initial plasma is presented, and the characteristics of the flashover trigger device made from ZnO dielectric material are investigated.…”

Investigation on 10/350 Crowbar Pulse Current Circuit

“…It is required that the crowbar discharging switch should meet special requirements, such as high hold-off voltage, short discharging delay time and delay jitter, wide operating voltage scope and high charge transferring energy. The pseudospark switch possesses the above advantages, but its low hold-off voltage limits its application to high voltage and high current circumstances, and the current peak of 10/350 µs produced by the pseudospark crowbar pulse current circuit reaches a current of only 25 kA or so [2,3] . TVS(triggered vacuum switch) integrates strong vacuum insulation characteristics into fast spark switch controlling features.…”