Providing HTS Solutions for a New Dimension in Power – TODAY!

2G HTS Wire Produced in Pilot-scale Manufacturing at SuperPower and Application in Prototype Devices

Partially funded through Title III Program & DOE (UT-Battelle), AFRL & AFOSRSupported by CRADAs with Los Alamos, Oak Ridge, and Argonne National Laboratories

ACASC, Xi’an, China ● Dec. 2 – 4, 2007

Yi-Yuan Xie, Y. Chen, X. Xiong, X. Zhang, Y. Qiao, A. Rar, J. Reeves, K. Lenseth, R. Schmidt, M. Martchevskii, D. Hazelton J. Herrin, and V. Selvamanickam

ACASC 2007 – 2 –

SuperPower’s 2G wire is based on high throughput processes & superior substrate

High throughput is critical for low cost 2G wire and to minimize capital investmentSuperPower’s 2G wire is based on high throughput IBAD MgO and MOCVD processesUse of IBAD as buffer template allows us the choice of any substrate• Advantages of IBAD are high strength, low ac loss (non-magnetic, highly

resistive substrates) and high engineering current density (ultra thin substrates)

2 μm Ag

20μm Cu

20μm Cu50μm Hastelloy substrate

1 μm HTS~ 30 nm LMO

~ 30 nm Homo-epi MgO~ 10 nm IBAD MgO

< 0.1 mm

ACASC 2007 – 3 –

SuperPower’s 2G Pilot Manufacturing facility has been operational since 2006

Pilot IBAD

Majority of investment already made for 1000 km/year capability

Pilot HTS

Pilot Substrate Electropolishing Pilot Buffer

5 m Test Rig

• Producing marketable 2G HTS wire: high performance, large quantity and low cost • Focus on three key metrics: high Ic, high throughput and long length

ACASC 2007 – 4 –

Pathway to commercialization of 2GMetric 1 : Higher Currents

Thick film MOCVD technology continues to advance Demonstrated 300 A conductor in 4 mm width, 50% better than today’s best 1G.

-2

0

2

4

6

8

10

12

0 200 400 600 800 1000

Current (A)

Volta

ge (m

icro

volt)

200

300

400

500

600

700

800

0 0.5 1 1.5 2 2.5 3 3.5 4

MOCVD film thickness (microns)

Criti

cal c

urre

nt (A

/cm

)

2

2.5

3

3.5

4

4.5

Jc (M

A/cm

2 )

2006 Ic (Y,Sm)BCO2007 Ic (Y,Gd)BCO2007 Jc (Y,Sm)BCO2007 Jc (Y,Gd)BCO

Critical current measured across entire tape width of 12 mm (no patterning)

Microstructural problems increase with increasing film thickness.

Can high currents be achieved in thinner films ?

In a 2.8 micron film made in 4 passes, achieved Ic of 740 A/cm (Jc = 2.64 MA/cm2) over reel-to-reel processed 12 mm wide, 10 cm long tape.

Ic measurement using continuous dc current (no pulsed current) across entire tape width of 12 mm No patterning

Ic = 888 A = 740 A/cm

ACASC 2007 – 5 –

Pathway to Commercialization of 2GMetric 2: Higher Throughput

180345345360Speed of 4 mm wide tape (m/h)

June 07

Oct. 06

Month

1440

360

IBAD MgO

1380

240

Homo-epi MgO

1380

240

LMO

720

135

MOCVD YBCOProcess

Production Capacity (km/yr)(if 45% uptime)

0

50

100

150

200

250

0 25 50 75 100 125

Position (m)

Crit

ical

cur

rent

(A/c

m)

Minimum Ic = 201 A/cm over 130 mUniformity = 3.5%

Min Ic

Oct. 06: High currents demonstrated over 200+m with all processes at high speedsall processes at high speeds

June 07: High currents over 130+m with all processes at even higher speedsall processes at even higher speeds

050

100150200250300

0 50 100

150

200

Position (m)

Crit

ical

cur

rent

(A/c

m)

Minimum Ic = 227 A/cm over 201 mUniformity = 2.7%

ACASC 2007 – 6 –

Higher currents in 100+ m lengths at higher HTS processing speeds

Oct 2007: produced 155m long wire in Pilot MOCVD systemTape speed ~ 70 m/h*Minimum Ic over 155 m

= 320 A/cmUniformity over 155 m = 2.5%

In 2006, we demonstrated Ic ~ 300 A/cm over 100 m in MOCVD tape processed in Research MOCVD system. Tape speed = 15 m/h*Uniformity over 103 m = 6.8%

* 4 mm wide tape equivalent

Thicker film MOCVD technology successfully transitioned to Pilot system to produce long high current tapes at ~ 5x higher speeds

0

50

100

150

200

250

300

350

400

5 15 25 35 45 55 65 75 85 95 105

115

125

135

145

155

Position (m)

Crit

ical

cur

rent

(A/c

m)

0

50

100

150

200

250

300

350

400

1 11 21 31 41 51 61 71 81 91 101

Position (m)

Criti

cal c

urre

nt (A

/cm

)

ACASC 2007 – 7 –

Buffered tapes: produced kilometer lengths with complete 5-layer buffer stack and excellent & uniform in-plane texture

Ag

20μm Cu

20μm Cu50μm Hastelloy substrate

HTSLMO

Homo-epi MgO

IBAD MgO

0

1

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5

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7

8

9

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900

1,00

0

1,10

0

1,20

0

1,30

0

1,40

0

Position (m)

In-p

lane

text

ure

(deg

rees

)

Tape 1Tape 2Tape 3Tape 4Tape 5Tape 6Tape 7Tape 8Tape 9Tape 10

Tape Length Uniformity(m) Average Min Max

1 1,001 6.79 6.20 7.84 6.2%2 1,343 6.33 5.80 7.16 3.3%3 1,346 6.85 6.00 7.35 2.1%4 1,372 6.20 5.83 6.68 2.2%5 1,375 6.58 6.23 7.14 2.5%6 1,277 6.59 5.80 7.09 2.1%7 1,346 7.09 6.66 7.79 2.9%8 1,265 6.81 6.30 7.12 1.7%9 1,246 6.33 5.47 7.13 2.4%

10 1,369 6.18 5.95 6.26 1.2%

In-plane texture (°)

Pathway to commercialization of 2GMetric 3: Long Lengths

ACASC 2007 – 8 –

0

50

100

150

200

2500 50 100

150

200

250

300

350

400

450

500

550

600

Position (m)

Crit

ical

cur

rent

(A

/cm

)

Minimum Ic = 173 A/cm over 595 m

January 2007: crossed an important milestone of 100,000 A-m

0

50

100

150

200

250

300

350

0 100 200 300 400 500 600 700 800

Position (m)

Crit

ical

cur

rent

(A/c

m)

Sept. 2007: New long length record !

Minimum Ic = 190 A/cm Ic × Length (790 m) = 150,100 A-mUniformity over 790 m = 9.7%

We are getting very close to kilometer long 2G wire!

Speed of 4 mm tape (m/h)

Process (single pass)

360IBAD MgO345Homo-epi MgO345LMO

~ 100MOCVD

77 K, Ic measured every 5 m using continuous dc currents over entire tape width of 12 mm (not slit)

ACASC 2007 – 9 –

10

100

1,000

10,000

100,000

1,000,000

May

-02

Oct

-02

Mar

-03

Aug-

03Ja

n-04

Jun-

04N

ov-0

4Ap

r-05

Sep-

05Fe

b-06

Jul-0

6N

ov-0

6Ap

r-07

Sep-

07Fe

b-08

Criti

cal C

urre

nt *

Leng

th (A

-m)

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000N

ov-0

1

Mar

-03

Aug

-04

Dec

-05

Apr-

07

Cri

tical

Cur

rent

* Le

ngth

(A-m

)Remarkable progress in 2G wire scale-up over the last 5 years

62 m18 m1 m 97 m

206 m

1 m to 790 m in 5 years

Also, Ic doubled & speed

increased 12-fold to 180 m/h*

158 m

322 m427 m

595 m

World Record

*4 mm speed equivalent

790 m

ACASC 2007 – 10 –

Substantial improvements made in 2007 in all key metrics -Ic & speed, & piece lengths of 2G wire

Rapid progress with higher currents, higher speeds, and longer lengths are all leading the way to a lower-cost 2G wire

84%

85%

150%

Same Ic level with much higher speeds in all processes

33%

40 to 50%

30% higher Jc

Improvementin 2007

1,375550Buffered tape piece length (m)

790427Completed 2G wire Piece Length (m)

150,100

201

180

345 to 360

740 in 2.8 micron film

2007

240Buffer speed* (m/h)

135MOCVD speed* (m/h)

227Ic over 100 m at stated speeds of Buffer & MOCVD

81,550Ic × L (A-m)

721 in 3.5 micron film

Ic (A/cm) – short, reel-to-reel processed

2006Metric

*4 mm wide tape equivalent, single pass

ACASC 2007 – 11 –

Progress being made both in Pilot Manufacturing of long lengths & technology development with shorter lengths

Next Steps:Manufacturing scale-up to reach 1000 m with Ic > 200 A/cm (almost there !)Manufacturing improvements to raise Ic level of 500+m Production lengths to that of short lengths of same film thickness i.e. 500 m and then 1000 m with Ic > 300 A/cmTechnology transition of higher-Ic conductors to Pilot manufacturing, i.e., 100 m, then 500 m and then 1000 m with Ic of 500 A/cm

0

100

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500

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700

8000.

01 0.1 1 10 100

1000

Length (m)

Crit

ical

cur

rent

(A/c

m)

1 micron thick HTS Standard in Pilot MOCVDProduction system

2.8 micron thick HTS

1.4 micron thick HTS

Title III goal June 2008

~ 2.3 micron HTS in Pilot MOCVD Production system

ACASC 2007 – 12 –

2G wire cable winding 3 core stranding

Nearly 10,000 m of 2G wire in 43 m piece lengths and minimum Ic over 70 A was delivered by SuperPower in Dec. 2006, marking the single largest delivery of 2G wire

30 m 2G Cable has been manufactured & tested by Sumitomo with ~ 10,000 m of our 2G wire

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

ACASC 2007 – 13 –

Excellent overall performance obtained in 2G cable

Ic of conductor layers ~ 2660 – 2820A (DC, 77K, 1μV/cm)

Ic of shield layers ~ 2400 – 2500A (DC, 77K, 1μV/cm)

-0.5

0

0.5

1

1.5

2

0 500 1000 1500 2000 2500 3000Current (A, DC)

Elec

trica

l Fie

ld(u

V/cm

)

Core-1Core-2Core-3

Ic Criterion (1uV/cm)

0.001

0.01

0.1

1

100 1000 10000Loading Current (Arms, 60Hz)

AC

loss

(W/m

/pha

se)

Measured value

0.34 W/m/ph @ 800 ArmsAlmost same result as previous

1 meter test 2G cable

No Ic degradation and No defect was found at dismantling inspection when bend to a diameter of 2.4 m

Cable withstood AC 69kV for 10 minutes and Impulse ±200kV, 10 times

ACASC 2007 – 14 –

2G Cable has been installed in grid at Albany Cable site

Installation at Albany Cable site (Aug. 5, 2007)

• Assembly of joint between 2G & 1G cables completed

• Terminated assembly completed• 2G cable cool-down began late Nov. 2007 and

will be energized soon thereafter

• World’s first in-grid cable, first underground HTS cable, first cable-to-cable joint, 350 m long

• On-grid operations began July 20, 2006• 30 m segment of 1G cable replaced by 2G cable

which is world’s first 2G device

ACASC 2007 – 15 –

New high field coil constructed with 2G wireTotal thickness of our 2G wire including copper stabilizer is only 0.095 mm which is ½ the thickness of 1G and other 2G wires. This is very useful for coil applications where higher number of amp-turns can be obtained.

In FY’06, we demonstrated a 2G coil that generated 1.1 T at 77 K and 2.4 T at 64 K

2006 2G coil• In FY07, we constructed a coil with 6 double

pancakes using 462 m of 2G wire.• The coil was tested in the National High

Magnetic Field Lab at FSU

2007 2G coil

ACASC 2007 – 16 –

0

2

4

6

8

10

12

0 50 100 150 200 250

Current (A)

Cen

tral

Fie

ld (T

)

4.2 K, no background field

World record performance achieved with 2G coil

78 A in 4 mm width (77 K, self field)

Average Ic of tapes in coil

~ 44.46 mT/ACoil constant~1.569 A/mm2 per ACoil Je~ 2772# of turns

~ 462 m2G tape used

12 (6 x double)# of Pancakes

~ 51.6 mmCoil Height

~ 87 mmWinding OD

19.1 mmWinding ID9.5 mm (clear)Coil ID

World record field for HTS coil: 9.8 T

Coil tested by H. Weijers, D. Markewicz, & D. Larbalestier, NHMFL, FSU

9.81 T4.2 K Central field – self field

612,6124.2 K Amp Turns @ Ic -self field

221 A4.2 K Coil Ic - self field

ACASC 2007 – 17 –

18

20

22

24

26

28

0 50 100 150 200 250 300 350

Current (A)C

entr

al F

ield

(T)

SuperPower 2G

OST Bi-2212 tape

Two concentric Hitachi Bi-2212 inserts

World record performance achieved with 2G coil

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)

This demonstration extends the potential of 2G over a wider application range

World record field for LTS or HTS coil: 26.8 T

Coil tested by H. Weijers, D. Markewicz, & D. Larbalestier, NHMFL, FSU

23.425.126.8Total field achieved (T)

5.45.17.8Additional

field generated (T)

125/11286275Winding Je (A/mm2)

1.02.10.46Conductor length (km)

1999 Hitachi 2- insert

2003 OST

2007 SP