Development of a small-bore, high-efficiency, helical coil electromagnetic launcher

This investigation presents the design, development, and testing results of a small-bore helical coil electromagnetic launcher (HCEL) that is able to accelerate a 160 gram mass to 56 m/s with an efficiency of 3.3 %. The HCEL has a bore size of 15 mm, a length of 250 mm, and a projectile mass of 160 g. The measured inductance gradient of the HCEL is more than a factor of 100 times larger than a conventional railgun at 45 /spl mu/H/m. The HCEL derives powered from a capacitor-based PFN which typically provides 11 kA current at a charge voltage of 350 V. A numerical model of the HCEL launcher is constructed in PSpice. Theoretical and numerical predictions of launcher performance are compared with experimental measurements, including projectile velocity, projectile voltage, inductance gradient, and launcher current. The measured results are in good agreement with theoretical predictions.