Passive quench protection techniques for non-insulated superconducting magnets
View Patent ↗According to some aspects, techniques are described for designing non-insulated (NI) high temperature superconductor (HTS) magnets that mitigate problems that may arise during quench initiation and propagation. Coupling the HTS material to a co-conductor along its length reduces the effective resistance of the conductive path along the HTS material when it is not superconducting, and that this leads to numerous advantages for quench mitigation.
1 . A magnet comprising:
a plurality of plates arranged in a stack that includes a first plate, the first plate comprising a conducting channel on a first side of the first plate, at least part of the conducting channel being arranged in a spiral path, the conducting channel comprising a coil comprising a plurality of windings of a non-insulated wire, the non-insulated wire comprising:
a stack of high temperature superconductor (HTS) tapes, wherein each of the HTS tapes comprises an HTS material and is surrounded by a cladding comprising a conductive material;
a co-conductor layer comprising a conductive cap; and
a layer of solder arranged between and in contact with the stack of HTS tapes and the conductive cap,
wherein the stack of HTS tapes is arranged within the conducting channel, the layer of solder is arranged over the stack of HTS tapes within the conducting channel, and wherein the conductive cap is arranged over the stack of HTS tapes and the layer of solder in the conducting channel such that the co-conductor layer caps the stack of HTS tapes within the conducting channel.
2 . The magnet of claim 1 , wherein a ratio between a thickness of the co-conductor layer and a thickness of the stack of HTS tapes is between 0.5 and 2.
3 . The magnet of claim 1 , wherein a ratio between a thickness of the co-conductor layer and a thickness of the stack of HTS tapes is between 0.2 and 5.
4 . The magnet of claim 1 , wherein a ratio between a cross-sectional area of the co-conductor layer and a cross-sectional area of the stack of HTS tapes is between 0.2 and 5.
5 . The magnet of claim 1 , wherein the plurality of windings of the non-insulated wire are wound around an axis aligned in a first direction, and wherein the HTS tapes of the stack of HTS tapes are stacked radially with respect to the axis.
6 . The magnet of claim 5 , wherein the co-conductor layer is arranged over the stack of HTS tapes along the first direction.
7 . The magnet of claim 1 , wherein the HTS material comprises a rare earth barium copper oxide (REBCO) material.
8 . The magnet of claim 1 , wherein at least one of the co-conductive layer or the conductive material comprises copper.
9 . The magnet of claim 1 , wherein the conductive material comprises copper.
10 . The magnet of claim 1 , wherein the first plate further comprises a plurality of cooling channels on a second side of the first plate, the second side opposing the first side.
11 . The magnet of claim 10 , wherein the first plate is formed from a first material in which the plurality of cooling channels and the conducting channel are formed, and wherein the first material comprises steel.
12 . The magnet of claim 1 ,
wherein the HTS material comprises a superconductor layer comprising a substrate, one or more buffer layers, and an HTS superconducting material, and
wherein a ratio of a cross-sectional area of the conductive material to a cross-sectional area of the superconductor layer is at least 0.75.
13 . The magnet of claim 12 , wherein the ratio between the cross-sectional area of the conductive material and the cross-sectional area of the superconductor layer is between 1.0 and 4.0.
14 . The magnet of claim 12 , wherein the ratio between the cross-sectional area of the conductive material and the cross-sectional area of the superconductor layer is at least 2.0.
15 . The magnet of claim 14 , wherein the ratio between the cross-sectional area of the conductive material to the cross-sectional area of the superconductor layer is between 2.0 and 4.0.
16 . The magnet of claim 1 , wherein the co-conductor layer comprises a stack of conductive non-superconductor tapes.