An analysis of force-reduced toroidal magnets

Superconductors alleviate the problem of Joule losses in electromagnetic devices, but an upper limit on large-scale electromagnets remains the difficulty in supporting the Lorentz forces within such a magnet. The problem is magnified if the materials are brittle, such as a ceramic superconductor. Recently, we discussed a possible solution to this problem: electromagnets with a force-reduced winding. Producing such a phenomenon may greatly reduce the size and support needed. Force-free finite geometries are not possible due to the limits of the virial theorem, but present-day magnet support masses are up to an order of magnitude greater than the virial limit. We present results from finite element calculations indicating that this design offers substantial improvement over conventional approaches