Square wave linear transformer driver based on the Blumlein-type pulse forming network and pseudospark switch.

Abstract

High-voltage square-wave pulses have significant potential in fields such as high power microwave and flash photography. It puts forward higher requirements on the pulse generator: fast front, flat-top, and a miniaturized, compact structure. To address these challenges, this paper presents a square-wave formation approach based on the combination of three advanced technologies: the multichannel pseudospark switch (MCPSS), which offers fast conduction, high power, and high frequency; the Blumlein-type pulse forming network (BPFN), known for its high voltage transfer efficiency, long electrical length, and ease of parameter adjustment; and the linear transformer driver (LTD), which features a modular structure and fast front. A single-stage LTD module is developed, and the waveform modulation techniques are discussed. Single-gap MCPSS, unequal-capacitance BPFN, and a magnetic switch are utilized to optimize output waveform. A square wave pulse with a voltage of 25.0 kV, a tf of 24.9 ns, a full width at half maximum of 94.3 ns, and a flat-top bottom width (tbw) of 77.8 ns (90% Umax ∼ 90% Umax) is achieved on a matched resistive load.