The invention relates to a superconducting electrical switch. The switch comprises two parallel branches of superconducting material in a loop, and a magnetic field generator which generates a time-varying magnetic field through the loop in a direction generally parallel to the axis of the loop. The magnetic field generator is selectively activated and de-activated to switch the electrical switch between a low-resistance state and a higher-resistance state. In the low-resistance state, there is no magnetic field through the loop and transport current flows through the loop. In the higher-resistance state, a magnetic field through the loop induces a screening current such that the sum of the transport current and the screening current is substantially equal to the critical current or is greater than the critical current of the superconducting material. The switch may be used in, for example, a rectifier or fault current limiter.

Provided is a DC magnetic field superconducting coil power supply device using a superconducting coil at low cost. A DC magnetic field superconducting coil power supply device 1 comprises: a superconducting coil 17; a power supply device 11 configured to supply a DC voltage; a plurality of chopper circuits 13 connected in parallel between one end of the power supply device 11 and one end of the superconducting coil 17; and a controller 18 configured to control the plurality of chopper circuits 13, wherein the controller 18 is configured to operate the plurality of chopper circuits 13 in a time-division manner when charging the superconducting coil 17.

A superconductor magnet system including a superconductor magnet including a plurality of field coils connected in series, each field coil having a plurality of turns including superconductor material. The system also includes a primary electric current source connected across the plurality of the field coils for supplying a DC electric current to the field coils to generate a magnetic field. The system further includes a secondary electric current source connected in parallel with the primary electric current source across a subset of the field coils for supplying an additional DC electric current to the or each field coil in the subset to modify or correct the magnetic field.

A novel cooling system for a superconducting electromagnet (740) that is suitable for use in satellite (700), or at least one or more components of the electromagnet (740) is disclosed. A satellite (700) and electromagnetic control system (705) for position control of such a satellite (700) are also disclosed. In one embodiment, the superconducting magnet control system (705) comprises at least one superconducting electromagnet (740) with at least one cooling element and at least one cryocooler (735). The cryocooler (735) is thermally coupled with the cooling element thereby enabling cooling of the superconducting electromagnet (740) or at least one or more components thereof through the cooling element solely by conduction cooling.

A high temperature superconducting, HTS, magnet system. The HTS magnet system comprises an HTS field coil, a temperature control system, a power supply, and a controller. The HTS field coil comprises a plurality of turns comprising HTS material; and a resistive material electrically connecting the turns, such that current can be shared radially between turns via the resistive material. The temperature control system is configured to control the temperature of the coil, the temperature control system comprising at least a cryogenic cool system configured to keep the coil below a self-field critical temperature of the HTS material. The power supply is configured to supply current to the HTS field coil. The controller is configured to cause the power supply to provide a current greater than a critical current of all of the HTS material.

A method for charging a superconductor bulk magnet includes: step a) charging the magnet charger system so as to generate a first magnetic field in the sample volume, the superconductor bulk magnet having a temperature T>T.sub.c (300); step b) cooling the superconductor bulk magnet to a temperature T<T.sub.c (400); step c) discharging the magnet charger system, which inductively charges the superconductor bulk magnet, such that the superconductor bulk magnet traps a second magnetic field in the sample volume (500). In step a), the field adjustment unit is set such that the first magnetic field generated by the magnet charger system in the sample volume includes a homogeneous magnetic field component and at least one non-homogeneous magnetic field component (300). The non-homogeneous field component is chosen so that the second magnetic field of step c) has a higher homogeneity than the first magnetic field of step a) in the sample volume.

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.