Patent · US Expired

Superconductive magnet having shim coils and quench protection circuits

US4689707A · kind A · utility

23Cited by
7References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 27, 1986
Grant dateAug 25, 1987
Priority date
Expiry dateMay 27, 2006

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S505/85
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A superconductive magnet has a main coil for creating a primary magnetic field and a plurality of shim coils for correcting aberrations in different gradients in the primary field. The shim coils are also connected in shunt with shim quench heaters and with superconductors which together with the shim coils form a plurality of persistent loops. A plurality of protective heaters are electrically connected to the main coil and are thermally connected to the superconductors. When quenching begins in the main coil, current is diverted through the protective heaters causing them to heat. This increases the temperature of the superconductors in the persistent loops causing them to switch from the superconductive to the resistive state and divert current into the shim quench heaters. These heaters in turn heat the shim coils and drive the shim coils resistive to safety dissipate any energy therein.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.