Study of an angular distribution compact low impedance Blumlein-type pulse forming network

Abstract

The pulse forming network (PFN) has the advantages of compactness and long-pulse achievability, and is widely used in military and industrial applications. In this paper, a novel Blumlein-type PFN is investigated numerically and experimentally. Specifically, the device is composed of five Blumlein-type PFN units, which are parallelly connected in the axial direction, and the LC elements of each unit are distributed in the angular direction. Dimensions of the PFN are only Φ 560 × 345 mm2 due to the novel compact structure. Small volume is necessary in military and industrial applications, especially for some mobile platforms. Electromagnetic coupling in the structure is theoretically analyzed to improve the performance of the device. Importantly, the impedance of the structure is only 1.5 Ω, which can efficiently reduce insulation difficulty at the same power level. In order to improve the performance of the PFN, a sharpening switch is added in the circuit. Simulation results show that a 170 ns quasi-square pulse is obtained on a 1.5 Ω dummy load, and the jitter of the flap-top is only about 2%. The PFN is built and preliminarily studied in our laboratory. Quasi-square pulses with a peak voltage of 3.1 kV are obtained on a water load of 2.1 Ω. The jitter of the flap-top is ∼3.9%. Experimental results show reasonable agreement with numerical analysis.