Design and investigation of a multichannel laser-triggered vacuum switch

Abstract

A laser-triggered vacuum switch (LTVS) is an advanced closing switch with nanosecond delay and jitter. In order to enhance hold-off voltage and extend the service lifetime of an LTVS, we designed a multichannel laser-triggered vacuum switch (MLTVS) utilizing a cone-shaped target electrode placed on the cathode platform. The fabrication and testing of the MLTVS is described in this paper. Experimental results show that the working voltage of the MLTVS with a gap distance of 12 mm is from 30 V to 20 kV. The threshold energy for triggering the switch is 0.4 mJ corresponding to a peak power density of 27.9 MW/cm(2). The triggering lifetime of a spot can reach up to 18,000 shots. In addition, the relationship between triggering lifetime and target materials is analyzed using a field emission scanning electron microscope. A hypothesis of the vacuum gap's triggering mechanism is discussed based on the measured results.

Modelling the initial plasma dynamics in a laser triggered vacuum switch

“…Ti and KCl were chosen as the target material because this kind of mixed target can generate initial plasmas and let the LTVS breakdown with a low laser energy, due to the low vaporization temperature of KCl and high laser absorptivity of Ti. [13][14][15][16][17][18] The simulation is performed in an axisymmetric geometry (x,r), where x-axis is perpendicular to the target surface and r-axis is parallel to the target surface. The diagram of the simulation is shown in Fig.…”

Evaluation of High Energy Density Plasma in Counter‐Facing Plasma Focus Device Driven by Laser‐Triggered Pulse Power System

“…One of the major advantages of laser systems is the ability to precisely specify discharge timing. With regards to laser systems, research and application has been carried out on gap switches and similar equipment . In addition, there has been research and development of high current capacity switches utilizing vacuum discharge .…”