Solenoid Type Shielding Coil Systems for a Small Scale SMES

One of the difficulties of a small scale SMES for applications such as power line control is a high pulse loss due to its rapid change of magnetic field at short time energy transfer. To reduce it, a shielding coil system, which is composed of a main superconducting coil and a normal shielding coil connected in parallel, was proposed. For the medium scale SMES, we have showed the possibility of a toroidal type shielding coil system which produces small stray field in environment. A solenoid type coil system, however, seems to be appropriate for a small scale one, because a coil system of solenoid configuration brings advantages of an ease of magnetic force support and a simple cryostat system. The stray field is restricted in narrow area due to its small dimension. A simple solenoid shielding coil, however, might give somewhat of field fluctuations to a main superconducting coil, and then correction shielding coils should be arranged in the system. The proper arrangements of correction shielding coils are discussed in terms of the reduction of field fluctuations on the superconducting coil.