Transverse capacitance coupling UV pre-ionization switch

This paper studies the effect of the UV illumination technology on gas switch in principle, analyzing and approving the feasibility of UV pre-ionization to the main switch from transverse capacitance coupling auxiliary spark. UV illumination from auxiliary gap makes initial electrons release from the cathode by photoemission, which can reduce the scatter of breakdown voltage effectively. The factors which affect the intensity of UV pre-ionization are analyzed, such as breakdown current peak, voltage and storage capacity of auxiliary gap. The experiment results show that the UV pre-ionization from transverse auxiliary gap with storage capacitor of pF-order which is apart from the main gap with a distance of 15 cm is feasible among nitrogen. On this basis, a new compact transverse capacity-coupling UV illumination switch is designed.