Abstract: A magnet includes a stack of a plurality of superconducting pancake wound coils having a stacking axis normal to a winding direction of the coils. The stack has axial ends and has a stack midplane relative to the stacking axis. A quench detector is provided for detecting a quench in the stack of superconducting pancake wound coils. A plurality of resistance quench heaters (RQH) are distributed symmetrically along the axis with respect to the stack midplane. Control circuitry is provided for controlling the operation of the RQH upon the detection of a quench by the quench detector. A method of quenching a magnet is also disclosed.

Abstract: A magnet includes a stack of a plurality of superconducting pancake wound coils having a stacking axis normal to a winding direction of the coils. The stack has axial ends and has a stack midplane relative to the stacking axis. A quench detector is provided for detecting a quench in the stack of superconducting pancake wound coils. A plurality of resistance quench heaters (RQH) are distributed symmetrically along the axis with respect to the stack midplane. Control circuitry is provided for controlling the operation of the RQH upon the detection of a quench by the quench detector. A method of quenching a magnet is also disclosed.

Abstract: Coils for superconducting magnets and methods of making coils for superconducting magnets and controlling the turn-to-turn contact resistance of coils. The coils include a REBCO superconducting tape coated with a layer of tin-lead solder, co-wound with an oxidized stainless steel tape. The inclusion of tin-lead solder on the REBCO tape and a layer of oxidation on the stainless steel tape advantageously allow for tuning of the turn-to-turn contact resistance of the coil, and advantageously mitigates the effect of repeated pressure cycling on the turn-to-turn contact resistance.

Abstract: An active quench protection system for a superconducting coil in a magnet includes a quench detector. An inductive heating device is configured to generate an electric field to inductively heat a portion of the superconducting coil. A processor can generate a quench signal responsive to the detection of a quench by the quench detector to cause the inductive heating device to generate the electric field to inductively heat a portion of the superconducting coil. A quench power source can supply a time varying current to the inductive heating device to generate the electric field responsive to a quench signal from the processor. A magnet and a method for the active quench protection of a superconducting coil in a magnet are also disclosed.

Abstract: An active quench protection system for a superconducting coil in a magnet includes a quench detector. An inductive heating device is configured to generate an electric field to inductively heat a portion of the superconducting coil. A processor can generate a quench signal responsive to the detection of a quench by the quench detector to cause the inductive heating device to generate the electric field to inductively heat a portion of the superconducting coil. A quench power source can supply a time varying current to the inductive heating device to generate the electric field responsive to a quench signal from the processor. A magnet and a method for the active quench protection of a superconducting coil in a magnet are also disclosed.

Abstract: An actively shielded superconducting magnet having a dipole shim coil for adjusting and fine-tuning an external or far fringe magnetic field produced by a main coil of the magnet. An active shield coil is coupled to the main coil in reverse polarity and produces a magnetic field when energized that opposes the far fringe field to substantially reduce the far fringe field. The dipole shim coil is electrically isolated from the active shield and main coils of superconducting magnet, and produces a magnetic field when energized that provides for the fine adjustment of any residual far fringe field.