METHOD AND APPARATUS FOR RELEASING ELECTRIC ENERGY

1,090,529. Superconductor devices. COMMISSARIAT A L'ENERGIE ATOMIQUE. Oct. 12, 1966 [Nov. 9, 1965], No. 45657/66. Heading H1K. Electric energy stored in a superconducting loop circuit is transferred to a load circuit via a low resistance metallic sheath which covers and contacts the superconductor over part of its length, a switch to break the loop circuit being provided in the uncovered superconductor portion. The Figure shows a superconductor 3 covered by a sheath 4 of copper or aluminium which may consist of a plurality of wires or a ribbon in which the superconductor is embedded. Switching means is provided by heater coil 7 which when energized heats the uncovered portion of superconductor 3 above its critical temperature. The sheath 4 is connected via terminals 11, 12 to a current generator 12; to establish the loop current, generator 13 provides a current in coil 1 through the sheath with switch 7 open; switch 7 is then closed to complete superconducting loop 3 which traps the circulating current when generator 13 is disconnected. Terminals 11, 12 are then connected to a load to which the stored circulating current energy is transferred when switch 7 is opened. Other forms of switching may be adapted such as breaking mechanical contact or the application of a high magnetic field. The turns of the coil 1 may be insulated from each other by a coating, e.g. aluminium oxide, on the sheath.