An Augmented Multiphase Rail Launcher With a Modular Design: Extended Setup and Muzzle Fed Operation

A novel approach toward electromagnetic launch is presented. In general, a railgun-type launcher is characterized by its unique ability to accelerate macroscopic masses (up to several kilograms) to speeds of 2 km/s. This is mostly done using capacitor banks in crowbar configuration resulting quasi-dc current profiles. The innovation of the work presented here is the use of multiphase current for driving railgun-type launchers. To this end, both the accelerator and the energy supply have to be redesigned. The use of ${n}$ multiple phases means that the accelerator has to have in principle n pairs of rails, meaning that also the armature differs strongly from classical solutions. One purpose of the project was to connect the launcher to the local power grid. Therefore, a corresponding generator had to be developed. A novel design characterized by the use of augmenting field coils is presented in that regard. In order to achieve high payload velocities with such a multiphase setup, several stages or modules are required. A system consisting of two modules is introduced here and experimental results are shown. The particular design using field coils allows for a mode of operation where a part of the current is fed from a subsequent module back to the muzzle of the preceding one leading to an increase of the propulsive force.