Recent Results in 2G HTS Wire Technology Development at … · 2020-07-29 · KSS 2008, July 9-11,...
Transcript of Recent Results in 2G HTS Wire Technology Development at … · 2020-07-29 · KSS 2008, July 9-11,...
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SuperPower, Inc. is a subsidiary of Royal Philips Electronics N.V.
Recent Results in 2G HTS Wire Technology Development at SuperPower
Program funding from Title III and DOE through UT-Battelle & AFRL. Supported by CRADAswith Oak Ridge, Los Alamos, and Argonne National Laboratories
Yi-Yuan Xie, Y. Chen, X. Xiong, X. Zhang, A. Rar, M. Martchevskii, Y. Qiao, A.Knoll, K.P. Lenseth, R.M. Schmidt, J. Herrin, D. Hazelton and V. Selvamanickam
Korea Superconductivity Society Annual Meeting, July 9-11, 2008
KSS 2008, July 9-11, 2008
SuperPower 2G HTS wire utilizes high strength substrates coupled with high throughput processing
• SuperPower’s 2G HTS wire is based on a high throughput thin film manufacturing approach permitting a wide choice of materials combinations
– Advantages include high strength, low ac loss (non-magnetic, high resistivity substrates) and high engineering current density (ultra-thin substrates)
• High throughput is critical for low-cost 2G wire to enable early commercial adoption
– IBAD-MgO based buffer technique– MOCVD for HTS layer: combination of high deposition rate and large deposition
zone 2 μm Ag
20μm Cu
20μm Cu50μm Hastelloy substrate
1 μm HTS
< 0.1 mm
< 0.2 μm Buffer stack}
KSS 2008, July 9-11, 2008
SuperPower’s 2G pilot manufacturing facility has been operational since 2006
Pilot Substrate Electropolishing
Pilot buffer Sputtering
Pilot MOCVD
• Majority of investment already made for 1000 km/year capability
Pilot IBAD
KSS 2008, July 9-11, 2008
SuperPower was the first and is still the only company to demonstrate pilot-scale 2G HTS wire manufacturing• In Dec. 2006, SuperPower delivered nearly
10 km of 2G HTS conductor in 2006 to build a 30 m long cable for the Albany Cable project, which is now the world’s first & only 2G device energized in the power grid.
• Largest single quantity of 2G delivery
• 225 segments delivered each with a piece length of 43 m – not a delivery of tapes from laboratory runs !
Albany Cable project: National Grid, 350 m long cable. World’s first in-grid cable, first underground cable, first cable-to-cable joint.
30 m 2G cable segment
Excellent demonstration of reproducibility & manufacturing viability of our processes
KSS 2008, July 9-11, 2008
30 m long, 3-phase, fully-shielded 2G cable constructed with SuperPower 2G wire
35 mm
Copper tapes2 layers of 2G conductorPPLP (thickness 4.5 mm)3 layers of 2G conductor
Stranded Cu wires with insulation (φ16 mm / 140 mm2)
HTS conductor
Core outer diameter
Protection layerHTS shield
Electric insulation
Former
Cu StrandedWire Former
Electric Insulation(PPLP + Liquid Nitrogen)
Stainless Steel DoubleCorrugated Cryostat
Cu Shield2G HTS(2 shield Layers)
2G HTS(3 conductor Layers)
135 mm
KSS 2008, July 9-11, 2008
2G wire cable winding 3 core stranding
2G cable was fabricated under nearly the same conditions as 1G cable previously made for Albany Cable project
30 m 2G cable manufactured & tested by Sumitomo with ~10,000 m of SuperPower 2G wire
KSS 2008, July 9-11, 2008
2G cable shows excellent critical current performance in all layers
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Elec
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Ic Criterion (1uV/cm)
Ic of conductor layers ~ 2660 – 2820A (DC, 77K, 1μV/cm)Ic of shield layers ~ 2400 – 2500A (DC, 77K, 1μV/cm)
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Ic Criterion (1uV/cm)
Conductor Shield
KSS 2008, July 9-11, 2008
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AC
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Measured value
Low ac loss measured in 2G cable; mechanical & high voltage test requirements successfully passed• Cable - 2.5 meter single core• Current loading by go & return through conductor and shield• Ac loss measurement using lock-in amplifier with electrical 4 terminals
0.34 W/m/ph @ 800 ArmsAlmost same result as previous
1 meter test 2G cable
Bend Test (18D: Bending Dia. = 2.4 m)• No Ic degradation• No defect was found at
dismantling inspection
Voltage tests (Based on AEIC):• AC 69kV for 10 minutes, • Impulse ±200kV, 10 times
KSS 2008, July 9-11, 2008
2G High field insert coil demonstration
~1.569 A/mm2 per ACoil Je
~ 2772# of turns
~ 44.4 mT/ACoil constant
~ 462 m2G tape used
12 (6 x double)# of Pancakes
~ 51.6 mmCoil Height
~ 87 mmWinding OD
19.1 mmWinding ID
9.5 mm (clear)Coil ID
Conductor:Dimensions: 4 mm wide x
95 microns thickSubstrate: 50 micron Hastelloy
HTS: ~ 1 micron YBCO
Stabilizer: ~ 2 micron Ag on YBCO
~ 20 microns of surround copper stabilizer per side
Tape Ic 72 – 82 A, 77 K, sf
Coil Winding
Double Pancake Construction
Dry Wound (no epoxy)
Kapton polyimide insulation (co-wound)
Overbanding: 316 Stainless Steel
KSS 2008, July 9-11, 2008
NHMFL facilities provide 19T axial background field
Insert coil tested in NHMFL’s unique, 19-tesla, 20-centimeter wide-bore, 20-megawatt Bitter magnet
2G High Field Insert Coil Showing Terminals, Overbanding and Partial Support Structure. Flange OD is 127 mm.
KSS 2008, July 9-11, 2008
High field insert coil achieves world records for highest HTS field, highest magnetic field by a SC magnet
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Current (A)
Cent
ral F
ield
(T)
19T background self field
3.2 T4.2K Peak Radial Field @ Ic, self field
2.7 T4.2 K Peak Radial Field @ Ic, 19 T bkgd (axial)
274.6 A/mm24.2 K Je @ Ic, 19 T background (axial)
9.81 T4.2 K Central field – self field
26.8 T4.2K Central Field – 19 T background (axial)
485,1004.2 K Amp Turns @ Ic –19 T background (axial)
175 A 4.2 K Coil Ic – 19 T background (axial)
346.7 A/mm24.2 K Je @ Ic, self field
612,6124.2 K Amp Turns @ Ic-self field
221 A4.2 K Coil Ic - self field
72 A – 82 A (77K, sf)
Ic of Tapes in Coil
26.8 T @ 175 A
9.81 T @ 221 A
Peak hoop stress ~ 215 MPa, well below tape limit
KSS 2008, July 9-11, 2008
Key metrics of 2G wire for broad market penetration
• Key metrics determining the price-performance characteristics of 2G HTS wire and qualifying for applications:
– Ic 500 A/cm at 0T & 77K– Ic(B) 100 A/cm at 1.5T &77K– L 1 km– V 1000 km/year
L (m)
Ic (A)
V (m/h)
KSS 2008, July 9-11, 2008
SuperPower’s 2G wire technology is based on high throughput processes
750Alumina + Yttria
360IBAD MgO
345Homo-epi MgO + LMO
180 (for ~ 1 μm HTS layer)MOCVD
Throughput of 4mm wide tape (m/h)Process
KSS 2008, July 9-11, 2008
Kilometer long tapes are routinely processed through IBAD MgO• High throughput established with IBAD enables 1000+m piece length processing
within hours!• Ion beam sputtering and assist condition stability must remain constant to obtain
uniformly good texture over 1000+m piece lengths.• On-line RHEED monitoring used to maintain texture uniformity over 1000+m
lengths
Over thirty 1,200 – 1400 m tapes have been successfully processed through IBAD MgO
1400 m long IBAD MgO
KSS 2008, July 9-11, 2008
Excellent in-plane alignment has been uniformly distributed on 1.3 km+ lengths
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Position (m)
FWH
M (d
egre
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FWHM of XRD phi scan at LMO (110)measured on one point in each meter
The FWHM values of the phi-scan at (110) of LMO, the cap layer of the 5-layer buffer stack, typically range from 6 to 8 degrees for the km+ lengths
Al2O3
Y2O3
IBAD MgO
Homo-epi MgO
30 nm LMO∆Φ = 6o-8o
0.2 m
KSS 2008, July 9-11, 2008
High critical currents in long lengths processed at high speeds
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Position (m)
Crit
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cur
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(A/c
m-w
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measured every 5 m using continuous dc currents over the entire 12mm tape width at 77K with a criterion of 0.2 microvolt/cm. Ic_minimum = 314A/cm on 202m length
• Minimum Ic = 314 A/cm over 202 m• processed with MOCVD throughput of 90m/h• Uniformity over 202 m = 2.4%
KSS 2008, July 9-11, 2008
High critical currents in long lengths processed at high speeds
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Criti
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measured every 5 m using continuous dc currents over the entire 12mm tape width at 77K with a criterion of 0.2 microvolt/cm.Ic_minimum = 221A/cm on 610m length
• Minimum Ic = 221 A/cm over 610 m• Processed with MOCVD throughput of 90m/h• Uniformity over 610 m = 2.65%
KSS 2008, July 9-11, 2008
High critical currents in long lengths processed at high speeds
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Criti
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measured every 5 m using continuous dc currents over the entire 12mm tape width at 77K with a criterion of 0.2 microvolt/cm. Ic_minimum = 170A/cm on 935m length
• Minimum Ic = 170 A/cm over 935 m• Processed with MOCVD throughput of 135m/h• Ic × L = 158,950m
KSS 2008, July 9-11, 2008
Capability of 320 A achieved in 4 mm widths
3.5 μm film made in 10 passes: Ic = 964 A = 803 A/cm (Jc = 2.06 MA/cm2)2.1 μm film made in 6 passes: Ic = 929 A = 774 A/cm (Jc =3.68 MA/cm2)
Ic measurement using continuous dc current (no pulsed current) across entire tape width of 12 mm. No patterning
2005 SmYBCO
2006 SmYBCO
2007 GdYBCO
2008 GdYBCO
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Crit
ical
cur
rent
(A/c
m-w
idth
)
Over 1.2 m lengthIc = 964 A = 803 A/cm
2005 SmYBCO
2006 SmYBCO
2007 GdYBCO
2008 GdYBCO
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KSS 2008, July 9-11, 2008
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Thickness (μm)
Jc (M
A/cm
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0.35 micron each pass
0.7 micron each pass
77K, 0T
Ic measurement using continuous dc current (no pulsed current) across entire tape width of 12 mm No patterning
Over 1 m length
Ic = 976 A = 813 A/cm3.33 μm, Jc = 2.44 MA/cm2
Ic=976A end-to-end of a 1m long 12mm wide tape
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Current (A)
Sign
al ( μ
V/cm
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Thichness (μm)
Ic (A
/cm
)
0.35 micron each pass
0.7 micron each pass
77K, 0T
High current wire processing is repeatable
KSS 2008, July 9-11, 2008
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Angle (degree)
Ic (A
/cm
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3.5micron recipe-02.8micron recipe-13.3micron recipe-2*
77K, 1T
Dramatic improvements achieved in in-field performance of SuperPower 2G wire
For 3.3micron film of recipe-2*Ic_minimum(77K, 1T) = 185.6A/cmIc_minimum(65K, 3T) = 267.3A/cmIc(77K, B//c=3T) = 71.8A/cm
For 0.7micron recipe-2*Recipe-1: strong pinning for B//abRecipe-2*: strong pinning for B//c
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Ic (A
/cm
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0.7micron recipe-00.7micron recipe-10.7micron recipe-2*
77K, 1T
Data from Y. Zhang, M. Paranthaman, A. Goyal, ORNL
Best in-field performance in commercial 2G wire
KSS 2008, July 9-11, 2008
Mechanical properties of SuperPower 2G wire is far superior to RABiTS-based 2G wire
*Measurements Y. Zhou and K. Salama (U.Houston)
550 MPa1200 MPaHigh-strength 50 micron substrate
350 MPa650 MPa100 micron substrate
Critical tensile stress at RTYield strength at 77 K*2G wire made with
Conductor with 100 μm substrate
N. Cheggour, D. Van der Laan, J. Ekin (NIST)
Our 2G wire is 5 times stronger than competing 2G wire –can withstand high stress levels in operation
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Tensile Strain (%)
T = 76K
Batch 1Batch 3 Batch 2
Complete Conductor (100 μm)
Bare substrates (50 μm)
Complete conductor (50 μm)
Bare substrates (100 μm)
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2G with High-strength 50μm substrate
Stre
ss (M
Pa)
Strain (%)
KSS 2008, July 9-11, 2008
Excellent mechanical properties maintained even in 2G wire with 3 micron thick HTS films• Thick YBCO films will be needed to meet high current requirements.• To our knowledge, no other 2G wire manufacturer has published mechanical property data
on 2G wire with thick YBCO films
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inal
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Bend diameter (mm)
I c (A
/cm
-w)
4 mm wide 2G wire with 3 micron thick YBCO & 40 microns surround copper stabilizer
(data shown is average from 5 samples)
compression tension
95% Ic retention measured in axial tension & compression up to 0.5% even in tapes with 3 microns thick HTS layer
95% Ic retention measured in bending with YBCO in tension & compression down to a bend diameter of 13 mm even in tapes with 3 microns thick HTS layer
76 K
Measured by Danko van der Laan One
step
KSS 2008, July 9-11, 2008
Mechanical properties of 2G wire are ideal for high field, high stress applications
< 0.35 @ 0.4%Nb3Sn, 16 T
< 0.68 @ 0.4%Nb3Sn, 12 T
< 0.82 @ 0.4%Nb3Sn, 8 T
< 0.90 @ 0.4%Nb3Sn, 4 T
> 0.95 for ε ~ 0.35%
1G low strength
> 0.95 for ε ~ 0.40%
1G high strength
> 0.95 for ε ~ 0.45%
SP 2G
Ic / Icε=0Conductor
Ic retention vs. strain
Comparative Operating Stress-Strain Operating Windows for High Field Superconductors
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Stre
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SP 2G HTSHigh Je
High Strength 1G HTS Low Je
Nb3Sn Moderate JeLow Strength
1G HTSModerate Je
KSS 2008, July 9-11, 2008
Summary
• Prototype applications including cable and high field coil with SuperPower’s 2G wire demonstrated the viability for commercialization.
• SuperPower’s 2G technology development is focused on three key metrics for a broad market penetration and improvement has been made on all areas.
– High throughput:• 750m/h for sputtering Al2O3+Y2O3 base layer• 360m/h for IBAD MgO template• 345m/h for sputtering Homo-epi MgO+LMO buffer• 180m/h for MOCVD REBCO
– High Ic:• 813A/cm-width at 77K and self-field over 1 meter length
– Long lengths:• 314A/cm-width over 202m• 221A/cm-width over 610m• 170A/cm-width over 935m
• Superior mechanical properties and in-field performance make 2G HTS wires suitable for high field and high stress applications
KSS 2008, July 9-11, 2008
Questions?
Thank you for your interest!
For further information about SuperPower, please visit us at: www.superpower-inc.comor e-mail: [email protected]