Portable magnet power supply for a superconducting magnet and a method for removing energy from a superconducting magnet using a portable magnet power supply

1. A portable magnet power supply for a superconducting magnet comprising apparatus for the storage of energy released from a superconducting magnet, said apparatus comprising:

an electrical run-down load for connection across the electrical terminals of the superconducting magnet to receive energy released from the superconducting magnet in a ramping down of the superconducting magnet in a ramping down time span;

a heat storage material in thermal contact with the run-down load, said heat storage material having a heat storage capacity that stores substantially all of said energy in said ramping down time span; and

a housing in which said run-down load and said heat storage material are contained, said housing being configured to be manually portable and said run-down load and said heat storage material having a size and weight configured for manual transport of said run-down load and said heat storage material in said housing.

2. Apparatus according to claim 1 , wherein the heat storage material undergoes a phase change in response to energy released by the run-down load.

3. Apparatus according to claim 2 wherein the heat storage material comprises paraffin wax.

4. Apparatus according to claim 1 wherein the heat storage material comprises one or more ceramic bricks.

5. Apparatus according to claim 1 wherein the run-down load comprises one or more diodes.

6. Apparatus according to claim 1 wherein the run-down load comprises a resistive element.

7. A method for removing energy from a superconducting magnet using a portable magnet power supply, comprising:

manually bringing a non-stationary, portable magnet power supply to a site of a superconducting magnet, said portable power supply having a housing containing a run-down load and heat storage material;

connecting said run-down load of the portable magnet power supply across electrical terminals of the superconducting magnet;

in a ramping down of said superconducting magnet opening a superconducting switch to divert current flowing in the superconducting magnet through the run-down load, said current having an energy associated therewith and said ramping down procedure taking place in a ramping down time span;

storing substantially all heat generated by the run-down load in response to the current flowing through it during said ramping down time span in the heat storage material of the portable power supply; and

allowing the heat storage material to cool after current has ceased to flow through the run-down load.

8. A method according to claim 7 comprising storing heat in the heat storage material by a change in phase of the heat storage material, from solid to liquid; and the heat storage material reverting to a solid state on cooling.

9. A method according to claim 8 comprising employing paraffin wax as the heat storage material.

10. A method according to claim 7 comprising employing a number of ceramic bricks as the heat storage material.