Characterization of EM Emission During the Operation of Solid and Plasma Armature Rail Launchers

We present the results of an experimental analysis aimed at investigating the electromagnetic (EM) emission during rail launcher operation. In order to obtain such data, an experimental setup was assembled in a shielded semi-anechoic chamber, consisting of a pulsed power source-unit, a power coaxial cable and a rail launcher prototype. Several experiments were performed for different operating conditions and results were repeatable. Finally, we provide a qualitative modeling of some sources of electromagnetic transients and we discuss basic aspects driving the EM emission phenomena in railgun systems.

I. Introduction

There is a significant interest in the characterization of the electromagnetic emission during the operation of electromagnetic rail launchers and their associated pulsed power systems [1]. High levels of electromagnetic fields can create disturbances to electronic components in the projectile as well as to electronic devices in the surrounding electromagnetic environment [2]. A comprehensive study of such phenomena can help for a correct design and operation of the electromagnetic launchers. In a previous work, two of the authors studied the emission of radiated fields during the circuit-switch-on and plasma-armature-formation transient phase [3]. Experiments were performed using a low power railgun prototype. The most notable electromagnetic effect was associated with the switch-on transient. Fig. 1.

Schematic diagram of the experimental setup.