Coil Gun

Coil Gun Development

Why?

Two forces drove me to such madness.  First and foremost 6.131, Power Electronics, wanted a final project out of me.  The charging system for the capacitors and the discharge switching was a perfect example of Power Electronics knowledge, and so became a natural choice for a final project.  Secondarily, I’ve yet find an efficient coil gun design, and wondered what, if anything, I could do to increase efficiency in my design and experimentation.

Plan

There is a vast wealth of information available online about what a coil gun is and can look like and etc.  I assume a basic understanding of the E&M involved, but a quick overview of a coil gun’s operation for memory’s sake.  A coil gun is, in it’s most simple implementation, a coil through which a current is discharged, creating a magnetic field which links with a projectile, accelerating this projectile to an acceptable speed.  The only acceptable storage system to quickly discharge the current through the coil is a high voltage, surge rated capacitor.  Remembering that the higher the current in a coil, the higher the magnetic  field strength, it is apparent that a high voltage capacitor is necessary to achieve an acceptable field strength for true gun action.

In planning this project, I wanted to focus on meeting a few simple goals.  My design specs to start, for example:

Motorcycle Battery Power Source

Two – Three stage coil system

Compact enough to carry

Easy Charging of Battery

To implement these features the basic system would consist of a motorcycle battery charged from the wall, run through a boost converter to charge the high voltage capacitors, with an SCR switching system for discharge.