Youtube video of it in action.
This would mean a dramaticaly larger capacitor bank and equally large solid state switches. Whilst under construction I was approached by a Professor in the Engineering Department asking whether I could adapt it for use as a demonstration piece on electromagnetic acceleration. It only involved a few safety measures so I agreed and they gave me funding for components. The big buy was going to be a high current and voltage solid state switch. Luckily a Mitsubishi CM400HU-24F IGBT was supplied by a member of staff in the department who works on the power systems in trains.
Step 1: The Theory
This is the biggest disadvantage to coil guns, the current pulse length needs to be controlled in order to cut the power when the armature reaches the middle of the coil.
The second largest challenge to overcome with coil guns is delivering the electricity as quickly as possible. It stands to reason that the more energy you can put onto the coil gun, the more energy will be transferred into kinetic energy in the armature.
The main losses in this system are the eddy currents in the flyway tube and the projectile/armature, these can be minimised by slotting the flyway tube or using a non-conductive material. The projectile must be ferromagnetic thus this means that limiting eddy currents cannot be achieved by using a non-conductive material. The best solution to this is to use a powdered Iron in epoxy resin matrix. Although this improves initial efficiency it also removes the ability for the gun to be operated as an ‘inductance coil gun’.