High Field Magnet R&D with YBCO

Superconducting Magnet Division

Ramesh Gupta High Field Magnet R&D with YBCO July 26, 2011 Slide No. 1EUCARD2 VIDEO CONFERENCE

High Field Magnet

R&D with YBCORamesh Gupta

Brookhaven National LaboratoryNew York, USA



Relevance of HTS R&D at BNL to LHC-HE

BNL has a significant HTS R&D program with a large portion of it directly

related to high field magnets

At this early stage, the question is: Can we learn to use HTS (which is very

different from LTS) to make high field magnets (irrespective of the geometry)

Can HTS magnets (with different quench properties) with large stored energy

be protected? A million dollar question with a million dollar R&D program

Currently funded programs for next 2 years with sizable YBCO coils:

20+ T HTS (then more) with number of coils using ~3 km of YBCO tape

~25 T large bore magnet using about a million dollars of YBCO

8 racetrack coils, each using ~1 km, 4 mm equivalent tape

Join us NOW to get real experience and help make above programs successful



BNL/PBL SBIR for High Field Solenoid (Ultimate Goal ~40 T)

• Required coils with 2G HTS built and tested in LN2

• Technology proved for 20+T with background field@NHMFL

• Next phase:

• Demonstrate a well protected 20+ T HTS magnet

• Demonstrate higher fields with LTS & background field

Join us now for remaining challenging tasks

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Ic (

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Coil I.D.

Proof: Coils with the second generation HTS Can be Built and Tested Consistently without Degradation

Field parallel ~0.5 T; field perpendicular ~0.3 T @40 A



High Field HTS Magnet for SMES

(Partners: BNL, SuperPower & ABB)

Field: ~25 T

Inner Diameter : ~100 mm

Conductor: ~10 km, 12 mm wide 2G tape

Stored Energy: 2.5 MJ

Ramp up and ramp down time : 10 minutes

Large bore HTS Magnet for Superconducting Magnetic Energy Storage (SMES)

• Conductor: Develop 600 A (~500 A/mm2) at 30 T in any field direction• Magnet/coil technology: Very large stress and strain on conductor• Quench protection: Self stated overall risk rating to program – high

Many questions are similar to accelerator magnets

High risk, high reward R&D with several challenges – join us now



HTS Quench Protection R&D at BNL (development of hardware and understanding)

We recognize that quench protection in HTS poses a major challenge.

Significant R&D program on hardware, software, measurements for scientific

understanding, etc. is underway with funding from several sources:

• SMES

• FRIB

• PBL/BNL SBIR

• Base program

• LDRD (funding decision awaited)

A budget of ~1 M$ shows the level of interest.

But all areas are still not covered.

We welcome collaborations.



Large Racetrack Coils with YBCO

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• The baseline design of Quadrupoles for the Facility for Rare Isotope Beams (FRIB) consists of significant size HTS racetrack coils

Each coil uses over 1 km equivalent of standard 4 mm 2G HTS tape

• Unique opportunity to test large 2G HTS coils made with tape from multiple US vendors

• 8 coils built (4 with SuperPower and 4 with ASC)

• Successful construction, test and demo of quench protection of large HTS coils should be useful to LHC upgrade.

• The current plan, however, is limited to medium field ~40 K testing (FRIB need).

• Additional 4K high field tests of these large size HTS racetrack coils could provide useful technical data for LHC.

Coil with 4 ply 2G ASC Tape



A Magnet for Background Field Coil Testing

• A magnet has been designed and built with a large clear space for efficient

testing of HTS insert coils in high background field (no need to disassemble)• Major difference from preparing a magnet every time for each insert coil test• Large clear space: ~240 mm high, ~30 mm wide, ~500 mm long• Successfully tested at self-field of 10.4 T (higher field with insert coils)

This unique magnet is safely stored – can be brought into service with proper collaboration/funding



Alternate Approach for Magnets with 2212 Rutherford Cable:

React & Wind

Wire: Showa, Cable: LBL, Reaction: Showa, Test: BNL

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HTS Coil Production No.

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Earlier coils <1 kA (~2001)

Later coils 4.3 kA (10/03)

Self-field <0.05 T

Self-field ~ 1.85 T

R&W Bi2212 cables, coils & magnets carried significant current (still record?)

Coil wound and tested@BNL in a common coil magnet

Two approaches:• Develop conductor to do what we are used

to• Develop magnet designs to fit the

conductor

Ultimate goal is to develop accelerator technology to do physics (not certain type of conductors or magnets). We (both magnet scientists and machine physicists) have time to learn how to use these new conductors.

Recall history: Copper Vs. SC magnets



SUMMARY

• BNL has a significant HTS R&D program which covers a wide range. A large

part of it will directly benefit LHC-HE upgrade with high field magnets.

• All are invited join us in this exciting R&D

Benefit to participants: real hands on experience beyond paper studies.

Benefit to us: extra support and your intellectual contribution.

• We don’t have extra funding to provide direct support but believe at present

we have several programs to provide early opportunity to understand the

challenges associated with high field HTS magnets and develop technology for

future.

• At an individual level, collaborators will find unique challenges and be able to

make contributions of lifetime. Such opportunities don’t come too often.

High Field Magnet R&D with YBCO

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