Study on the Characteristics of Magnetic-Field Arrangement of Synchronous Induction Coilgun

Energy-conversion efficiency directly determines the scale of the synchronous induction coilgun, which is an important index to evaluate the launch system. Therefore, the method of improving the energy-conversion efficiency is one of the hot spots in the electromagnetic launch research. By changing the direction of the magnetic field, the acceleration mechanism of the armature has changed. This article focuses on the characteristics of the magnetic field arrangement of the multistage synchronous induction coilgun in order to obtain the design method of the magnetic field. First, the acceleration mechanism of the armature is analyzed for the consistent and inconsistent directions of the magnetic field. The feasibility of changing the magnetic field direction to improve the energy-conversion efficiency and the correctness of the simulation model is verified by the experimental results. The variation in the armature velocity and the single-coil efficiency is investigated when the direction of the magnetic field changes once, twice, and thrice. The prediction model of the magnetic field arrangement is established. Based on this model, the magnetic field arrangement of the coils is predicted when the direction of the magnetic field changes twice or thrice and the parameters of the pulsed-power supply are changed. The predicted results are in good agreement with the simulation results. The influence of the caliber on the prediction result is analyzed. Finally, the prediction model of the magnetic field arrangement based on the armature velocity and the discharge-loop parameters under the efficiency threshold related to the launcher caliber is established. The prediction model proposed in this article can effectively improve the energy-conversion efficiency and provide a valuable reference for the design of the magnetic field of the multistage synchronous induction coilgun.