Fast-rise-time trigger source based on solid-state switch and pulse transformer for triggered vacuum switch

Triggered vacuum switch (TVS) is significant in the field of pulse power technologies, especially in high power application. Particularly, the rise-time of trigger pulse is important for paralleled TVSs which are frequently used to increase peak current. Trigger source based on pulse transformer and solid state switch has good reliability and low jitter, thus, the design of a fast-rise-time trigger source based on solid-state switch and pulse transformer is crucial for the parallel connected TVS. The work presented here extends the state of the art in the area of high power pulse generator. This paper introduces the design procedure of a pulse transformer based on closed magnetic core and a discharging circuit based on solid-state switches in detail. The influence of leakage inductance and distributed capacitance of the pulse transformer on the output pulse waveform are analyzed. PSPICE simulations are studied to optimize the design of the pulse transformer. Based on the theoretical calculations and simulations, special winding structures, suitable material of magnetic core, and proper width of copper strip are carried out to obtain faster rise-time. Four parallel connected MOSFETs are used in the trigger source because of their anti-paralleled diodes and high switching-speed. The experimental results show that, the pulse transformer can generate a rectangular pulse with an adjustable amplitude of 0-5 kV, a pulse width of 0-5 μs, and the rise-time is about 160 ns. Lastly, the pulse transformer has a compact structure and can be used to trigger the TVS reliably.