This article proposes a method to design a three-stage induction coilgun system using the finite-element method (FEM). The system is designed to launch a 21.5 kg projectile. The method which is used to calculate the mutual inductance and the mutual inductance gradient between the two coils is expressed. Furthermore, the variation of mutual inductance and its gradient with respect to the distance between the two coils is indicated. The system parameters (i.e., coil currents, mutual inductance, mutual inductance gradient, force, velocity, and magnetic field distribution) are calculated and analyzed utilizing ANSYS Maxwell software. To verify the performance of the initial design, its analytical model is developed and validated in MATLAB software. The results of the analytical model are compared with the results obtained from the FEM method, and it is shown that they are well-matched in all waveforms. Besides, the efficiency of the system is improved through optimization by applying a genetic algorithm (GA). In this way, the efficiency of the system is enhanced from 29% to 36.6% and also the muzzle velocity is increased from 128 to 143 m/s. This method can be used to design a large-scale multistage induction coilgun (MSIC) for launching massive projectiles and reach high velocities.

中文翻译：

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多级感应线圈枪系统的设计、仿真和参数优化


本文提出了一种使用有限元法 (FEM) 设计三级感应线圈枪系统的方法。该系统设计用于发射 21.5 公斤的弹丸。给出了计算两个线圈之间的互感和互感梯度的方法。此外，还指示了互感及其梯度相对于两个线圈之间的距离的变化。利用ANSYS Maxwell 软件计算和分析系统参数（即线圈电流、互感、互感梯度、力、速度和磁场分布）。为了验证初始设计的性能，在 MATLAB 软件中开发并验证了其分析模型。将解析模型的结果与有限元方法获得的结果进行比较，结果表明它们在所有波形上都匹配良好。此外，通过应用遗传算法（GA）优化，提高了系统的效率。这样，系统效率从29%提高到36.6%，初速从128提高到143 m/s。该方法可用于设计大型多级感应线圈炮（MSIC），用于发射大型射弹并达到很高的速度。