Title :
Protection heater performance of Nb3Sn epoxy impregnated superconducting solenoids
Author :
Dixon, Iain R. ; Markiewicz, W. Denis
Author_Institution :
Nat. High Magnetic Field Lab., Tallahasse, FL, USA
fDate :
3/1/2001 12:00:00 AM
Abstract :
The response time of Nb3Sn coils with an active protection system is measured to quantify their performance during low current quenches. Tests are conducted on coils with bronze processed Nb 3Sn conductors of 0.23 and 0.41 copper fractions and placed in a background field up to 7 T. Stainless steel heaters imbedded within the epoxy at the outer diameter of the coils are employed to normalize the magnets uniformly along their axes. The heater circuit consists of up to four heater strips connected in series in which a square wave pulse is applied for a duration of one second. The quench reaction time is studied as a function of heater input power, number of active heaters, and fraction of critical current density
Keywords :
critical current density (superconductivity); epoxy insulation; niobium alloys; protection; superconducting coils; superconducting magnets; tin alloys; 7 T; Nb3Sn; Nb3Sn epoxy impregnated superconducting solenoids; Nb3Sn superconducting coils; critical current density; low current quenches; protection heater performance; quench reaction time; response time; square wave pulse; Coils; Conductors; Current measurement; Delay; Magnetic field measurement; Niobium; Protection; Testing; Time measurement; Tin;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
