Development of a 4 MV Laser-Triggered Multi-Stage Switch

A 22-stage 4 MV laser-triggered multistage multi-channel switch (LTS) was designed according to the hypothesis that the well-proportioned electrical field distribution is helpful in reducing the jitter of delay. Field distribution in the switch section is regulated by a metal field regulation ring and several gradient rings. In order to reduce the jitter further, a SF6/N2 mixture is chosen as the switching medium. The generalized standard deviation of the self-breakdown voltage and the deviation of the average value from the prediction is less than 4.4% and 13% respectively. Linearity of the self-breakdown voltage is better than 0.95. Triggered by a laser pulse of 35 mJ/3 ns, the delay is about 26 ns at a working voltage of 85%±3% USB (Self-breakdown Voltage). Maximum deviation of delay is less than ±2.5 ns. Jitter is less than 1.5 ns. The delay and jitter decrease with the increase in the working ratio (the ratio of working voltage to USB), pressure or voltage.