Electricity limitation device, in particular for short-circuit electricity limitation in energy transmission systems

摘要

1,163,027. Inductors; superconductor devices. SIEMENS A.G. 26 April, 1967 [26 April, 1966], No. 19319/67. Headings H1K and H1T. An electrical current-limiting arrangement comprises two parallel-connected windings 1, 2 wound to produce opposed magnetic fields, one of the windings 1, consisting entirely or partially of a superconductive material and having a critical current strength higher than the normal operating current of the winding, the windings 1, 2 being such that under normal operating current the resultant of the opposed fields is substantially zero and that when the critical current strength of the winding 1 is exceeded the winding 1 changes from its superconducting to a normally conducting state whereby the resultant of the opposed fields assumes a finite value and the inductance of the arrangement is increased. The other winding 2 may be of pure copper or aluminium or a superconductor. The windings may be housed in a cryo-vessel of a composite glass-fibre-plastics material, partially filled with liquid helium. In a further embodiment (Fig. 2, not shown), the windings may be of disc-form having alternating parts separated by thermal insulation (9), the winding 2 being cooled by the same coolant as winding 1 and operating at a higher temperature (e.g. 20‹ K.) than the winding 1 (e.g. 4.2-8‹ K.). The winding 1 may lie as far as possible in the field of the winding 2.