TRIGGERING CHARACTERISTICS OF SF₆ GAS SWITCH TRIGGERED BY XeClLASER

Experimental results arepresented on SF₆ gas switch triggering characteristics by XeCllaser (308nm).We have clarified the characteristics of breakdown threshold and energy absorption in SF,as a function of pressure.The power density of XeCl laser required for SF₆ breakdown (P) strongly changes with the change of pressure.As the pressure of SF₆ gas is 0.02MPa，the power density of XeCI laser for SF₆ breakdown P≈4.6GW/cm². For pressure around 0.48MPa, it approaches to the minimum (23.2GW/cm²). At high pressure the breakdown threshold increases to saturate to ≈ 4GW/cm². Excellent triggering behaviour for SF₆ gas switch has been obtained by LTGSsystem.For smallswitchwith self-breakdown voltage V_ab=60 kV, at the charge voltage V_ch≈0.96V_ab,we find delay time t_d≈20ns and jitter time σ≈260ps.