Efficiency Study of Hybrid Armatures With Coil Launchers of Different Calibres

Improving efficiency is a major area of research in the field of coil launchers. Two types of coil launchers are the reluctance coil launcher and the induction coil launcher. Reluctance coil launchers use a ferromagnetic armature, which is generally smaller in diameter due to the armature’s magnetic saturation and higher density, while induction coil launchers use a conductive armature, which is generally larger in diameter. To improve the efficiency of coil launchers, this article proposes a hybrid armature structure for coil launchers in which the front end of the ferromagnetic armature is placed at the end of the coil and connected to the conductive armature by an insulating material half the length of the coil. To compare the efficiency of the hybrid armature with that of the original armature, three coil launchers of 11.8, 18.4, and 50 mm bore were selected to simulate the hybrid armature with different parameters and to verify the consistency of the simulation and experiment of the hybrid armature. The final results show that the efficiency of the ferromagnetic armature is better than that of the hybrid armature at 11.8 mm aperture. At 18.4 mm, the hybrid armature efficiency is 9.12%, an improvement of 4.08% compared to the original ferromagnetic armature. At 50 mm bore, at 1000 V, the optimum efficiency of the hybrid armature is 3.17%, an improvement of 2.73% compared to an aluminum armature of the same mass with load, at 2000 V, the optimum efficiency of the hybrid armature is 7.87%, an improvement of 5% compared to an aluminum armature of the same mass with load, and at 3000 V, the efficiency of the hybrid armature is lower than that of the aluminum armature directly with load. The findings provide new and effective ideas for improving the efficiency of coil launchers.