Current limiting device for electromagnetic coil employing gap containing superconductive shield
US5355275A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 1991 |
| Grant date | Oct 11, 1994 |
| Priority date | — |
| Expiry date | Dec 20, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S336/01
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A variable impedance device comprises a coil (10) and an associated magnetic circuit (16) having a gap receiving a plate (20) of superconducting material which acts as a shield or barrier so that, while the plate (20) is in its superconducting state, magnetic flux is caused to traverse the gap via pathways substantially greater in length than the width of the gap. If a large current is passed through the coil (10), the plate (20) becomes resistive thereby presenting a substantially increased impedance to the current. The device may be used in current limiting applications, or other applications where a variable impedance is required.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.