Cutaway View Of A Flux Compression Generator. Image courtesy of the US Dept. Of Energy.

Flux Compression Generators
Tech level: 10
Explosive Power Generator (EPG) Weapon Cartridges
Tech Level: 14

Explosive Power Generators (EPGs) are a type of pulsed power generator. However, not all classifications of pulsed power generators use explosives, hence the distinction drawn here.

This articles deals exclusively with EPGs as energy sources. Discussion of their potential as electromagnetic pulse weapons will be discussed in another article.

EPGs use explosive charges to induce large spikes of current in specially configured equipment. Their great advantage is that they can be made much more compact than most other types of generators and can produce their power almost instantaneously, making hem ideal for a number of applications, particularly portable weapons technology.

Tech Level: 10

A technology that has been researched since the Cold War, it is used in a number of laboratory and research applications where large amounts of power needs to be generated almost instantly. Flux Compression Generators(FCGs) have also been of long-standing interest to the military, as they can also be used to create an electromagnetic pulse that renders all electronics and electrical systems in the affected area inert.

An FCG basically consists of an explosive charge inserted into or around a coil of copper or other conductive wires. The wires are charged from an auxiliary power source and the charge is detonated. The explosion causes the coil to generates a brief but intense fluxed magnetic field. This magnetic field is used to produce current in the coil, which can be fed to a device or capacitors in the split second before the wires are destroyed.

The physics of Magnetic Flux Compression is a fairly complex subject and is more thoroughly explained in the links at the end of this article. In essence, the explosive ‘compresses’ the magnetic flux of the field generated by the wires, creating an additional current in the wire. Because it happens near-instantly, electrical resistance factors don’t have time to kick in. This unfettered current multiplies the strength of the existing field immensely for a brief moment. The process destroys the generator, but is capable of producing currents as great as millions of amperes in a fraction of a second, up to over 60 times that of the starting current. For truly colossal power spikes, Flux generators can be rigged in series, where the current produced by one is used as the starting current in the next.

Flux generators have a number of design and engineering challenges. For maximum effectiveness, the detonation has to occur just as the initiating current in the coil is peaking, and getting the timing on those two systems exactly right can be tricky. The devices can also generate an intense electromagnetic pulse, so they usually have to be used with heavy shielding to protect nearby electronic devices. This is in addition to the usual precautions and protections must be taken when dealing with explosive equipment. If being used to power equipment or an experiment, both the debris and waste gasses of the explosion have to be cleared before another generator can be put in place.

Because of issues with electromagnetic pulse, developing FCGs for widespread commercial use would have a number of security and legal complications that would have to be resolved first. It is therefore unlikely that we will see them in commonplace use anytime soon.

Tech Level: 14

These are mentioned in the Traveller tabletop RPG, and would seem to be a natural outgrowth of Flux Compression Generators. Basically, FCGs would become compact and efficient enough to be integrated into portable weaponry and other equipment, from artillery and vehicle weapons to rifles and handguns.

Functionally, they would operate in many ways similar to weapon magazines. Individual cartridges would be relatively small and cylindrical. Each different weapon system would likely have its own specially-designed cartridges, depending on its power requirements, though some manufacturers may deliberately design different weapons to take the same EPG cartridges in order to simplify manufacturing and reduce costs. The cartridges would be arrayed in magazines, and would be loaded and unloaded into weapons in a similar manner.

Some weapons, such as railguns and coilguns, use projectiles as well as large amounts of current. With these technologies, the explosive charge would serve a dual purpose, both to power the weapon and to give the projectile an initial kick in velocity before it is accelerated electromagnetically. These weapons may end up having mechanical ammunition feed systems similar to modern day firearms, in order to load the EPG/projectile bundle into the barrel and then eject the spent cartridge and waste gasses after.

Other high-energy-use weapons, such as plasma guns, particle beams, and so on, would not necessarily need such mechanical feed systems. The magazine could be designed that each cartridge could be used directly in place without the need to be fed into the main gun mechanism. This would be dependent on being able to manufacture cartridge magazines durable enough to withstand numerous internal explosion without damaging the unused cartridges. An added advantage to such a system would be that the magazine could be designed to use two or more cartridges in series, with one EPG’s output serving as the starter current for the next, allowing the user to dial-up the weapon’s potential power substantially depending on how many cartridges are used at once.

There are some downsides to this system. For one, the internally-contained explosion will add a great deal of heat to weapon systems that will likely already generate quite a bit. Advanced coolant systems will have to be made even more robust and efficient to handle this, and weapons may need a cooling-down period between shots.

Second, the internal explosion will add vibrations and kickback to the weapon, though probably not as much as modern guns. Still, the user may have to steady the weapon after each shot to compensate for the recoil. Just as in some modern guns, waste gasses from the EPG could be vented at strategic points in order to help stabilize the weapon.

Also, the internal explosion will likely not be completely muffled, meaning the ideal of a completely silent beam weapon may never be realized. This will be especially true if the very energetic waste gasses are vented, resulting in a very gun-like bang with each pull of the trigger.

Because the EPGs’ detonations would be contained entirely within a properly shielded weapon and/or magazine, its environmental EMP effects would be neutralized.


In Print:

Fire, Fusion, and Steel: The Traveller Technical Architecture

On The Web:




Article added 2/14/09