Study of Single-Stage Double-Armature Multipole Field Electromagnetic Launcher

Multipole field electromagnetic launcher (MFEL) is a new type of coilgun that can produce larger radial magnetic field compared to the axial magnetic field, the axial acceleration force of coilgun mainly come from radial magnetic field. Because of the similarity of the magnetic fields between inner and outer regions of MFEL, this paper proposed a double-armature MFEL. One armature coaxial with the drive coil placed inside of MFEL; the other armature coaxial with the drive coil placed outside of MFEL. A single-stage double-armature MFEL was studied by simulation and experimental methods. The simulation results indicated that the muzzle velocity of the double-armature launch is similar to that of the single-armature launch, and the efficiency of double-armature MFEL is obviously larger than that of single armature. To verify the conceptual feasibility, a small-size single-stage double-armature capacitor-driven MFEL was built and tested. The inner small armature weighs 63.13 g, the outer big armature weighs 88.38 g. The experimental results on single-armature launch show good consistency with the simulation results, but there is a little gap between the experimental results on double-armature launch and the simulation results. The causes of the existing differences are considered to be mainly from the consistency difference between the six driving coils and the mutual influence between the inner and outer armatures.