The present invention provides a rare earth cold accumulating material particle comprising a rare earth oxide or a rare earth oxysulfide, wherein the rare earth cold accumulating material particle is composed of a sintered body; an average crystal grain size of the sintered body is 0.5 to 5 ?m; a porosity of the sintered body is 10 to 50 vol. %; and an average pore size of the sintered body is 0.3 to 3 ?m. Further, it is preferable that the porosity of the rare earth cold accumulating material particle is 20 to 45 vol. %, and a maximum pore size of the rare earth cold accumulating material particle is 4 ?m or less. Due to this structure, there can be provided a rare earth cold accumulating material having a high refrigerating capacity and a high strength.

In a method and system for shutting down a superconducting magnet of a magnetic resonance apparatus using a monitoring processor and an energy store, the monitoring processor determines stored energy stored in the energy store at a first point-in-time, and determines a ramp energy required for shutting down, and determines a second point-in-time based on the stored energy and the ramp energy. At the second point-in-time, shutting down of the superconducting magnet is begun.

An apparatus including an electrically conductive coil which produces a magnetic field when an electrical current passes therethrough; a selectively activated persistent current switch connected across the electrically conductive coil; a cryostat having the electrically conductive coil and the persistent current switch disposed therein; an energy dump; at least one sensor which detects an operating parameter of the apparatus and outputs at least one sensor signal in response thereto; and a magnet controller. The magnet controller receives the sensor signal(s) and in response thereto detects whether an operating fault exists in the apparatus, and when an operating fault is detected, connects the energy dump unit across the electrically conductive coil to transfer energy from the electrically conductive coil to the energy dump unit. The energy dump unit disperses the energy outside of the cryostat.

In a method and system for shutting down a superconducting magnet of a magnetic resonance apparatus using a monitoring processor and an energy store, the monitoring processor determines stored energy stored in the energy store at a first point-in-time, and determines a ramp energy required for shutting down, and determines a second point-in-time based on the stored energy and the ramp energy. At the second point-in-time, shutting down of the superconducting magnet is begun.

An apparatus includes an electrically conductive coil which produces a magnetic field when an electrical current passes therethrough; a selectively activated persistent current switch connected across the electrically conductive coil; a cryostat having the electrically conductive coil and the persistent current switch disposed therein; an energy dump; at least one sensor which detects an operating parameter of the apparatus and outputs at least one sensor signal in response thereto; and a magnet controller. The magnet controller receives the sensor signal(s) and in response thereto detects whether an operating fault (e.g. a power loss to the compressor of a cryocooler) exists in the apparatus, and when an operating fault is detected, connects the energy dump unit across the electrically conductive coil to transfer energy from the electrically conductive coil to the energy dump unit. The energy dump unit disperses the energy outside of the cryostat.

Devices and methods are provided for shutting down a magnet system. The device includes a portable housing, a communication unit, and a switch on the portable housing. The portable housing encloses a field shutdown initiation circuitry. The communication unit is disposed at least partially in the portable housing and the communication unit is configured to establish communication between the field shutdown initiation circuitry and the magnet system. The switch is configured to turn on the field shutdown initiation circuitry to initiate a magnet field shutdown in the magnet system.

Example coil guns and methods of using coil guns are described herein. An example coil gun includes a first pancake module; a second pancake module, where the first pancake module and the second pancake module are each formed of a winding with an inner superconducting material layer and an outer ordinary conductor layer, where the first pancake module and the second pancake module are physically and/or inductively coupled to propagate a quench of a superconducting state of the first pancake module to the second pancake module.

A coil device with at least one electrical coil winding with superconducting conductor material and a vacuum container is described in which the vacuum container surrounds the coil winding. The coil winding is part of a self-contained circuit for the formation of a continuous current. The closed circuit has a switchable conductor section, the conductor of which can be switched between a superconducting state and a normally conducting state by a magnetic device. The magnetic device has an internal part arranged inside the vacuum container and an external part arranged outside the vacuum container.

A Cryogen-Free (CF) type MRI superconducting magnet system capable of monitoring the conditions of the system components and, in case of a foreseeable quench, discharging the superconducting magnet at any desired discharge voltage before occurrence of quench.

An energy processing system and method for a magnetic coil, a coil unit, a superconducting magnet, and a magnetic resonance imaging system are disclosed. The system includes an energy conversion system configured to regulate voltage or current of coil energy during demagnetization, receive the coil's energy nonlinearly by collecting with a low voltage first followed by a high voltage, and output electric energy with a stable voltage or current adapted to an energy storage system. The energy storage system is configured to accumulate and store the converted energy. An energy release system is configured to release electricity stored in the energy storage system. A control system is configured to control the energy conversion system to perform energy conversion during coil demagnetization, and to monitor the energy storage system and the energy release system to implement charging and discharging control.