Transcript Innovation in the East of England

Superconductivity UK
Commercial superconductors
for motors and generators
Dr. Philip Sargent, Diboride Conductors Ltd.
Commercial Wire & Tape
• Commercial production:
• Niobium alloys (NbTi, Nb3Sn
etc)
• B2223 / silver tape - 1st Generation HTS
• Pre-commercial:
• MgB2
• Industrial laboratory:
• YBCO 2nd Generation HTS “coated conductor”
Superconductors
HgBa2Ca2Cu3O9
(under pressure)
160
140
TlBaCaCuO
Transition temperature (K)
120
Liquid Methane
LNG (112K)
B2223 - Bi2Sr2Ca2Cu3O
100
YBCO - YBa2Cu3O7
Liquid Nitrogen
(77K)
80
60
(La, Ba) Cu)
40
20
Hg Pb Nb
1910
Leigh Jarvis
Tl, Hg…(138K)
HgBa2Ca2Cu3O9
NbC
1930
NbN
Nb3Sn
MgB2
Nb3Ge
V3Si
1950
1970
1990
More superconductors
YPd2B2C
HoMo6S8 (Chevrel)
ErRh4B4
CeRu2 heavy fermion
1991 - K3C60 Fullerene
1994 - Sr2RuO4
2001 – MgB2
2001- C nanotubes
2002 - PuCoGa5 (18K)
1980- (TMTSF)2PF6
Nature 6 Mar.2003 - Na0.35CoO2•1.3H2O
HTS –complex copper oxides
B2223 - Bi2Sr2Ca2Cu3O
YBCO - YBa2Cu3O7
HTS –perovskite ceramics
Ba
Cu
O
Y
Ba
B2223 - Bi2Sr2Ca2Cu3O
YBCO - YBa2Cu3O7
Engineering Implications
• Requires near single-crystal microstructure
by complex processing,
• Oxide requires furnace treatment in
controlled oxygen atmosphere, in silver,
• Highly anisotropic resulting tape:
• Along and across tape,
• Sensitive to magnetic field direction!
B2223 multifilamentary tape -1
• Fill silver tube with
precursor powders.
• Reduce by extrusion,
swaging, drawing and
rolling to a monofilament alignedcrystal wire.
• Restack bundle in
another silver tube.
B2223 multifilamentary tape -2
•
•
•
•
Draw multifilament
Draw to align crystals
Roll to tape
Furnace heat treat
AMSC & Sumitomo
• AMSC &
Sumitomo have a
reciprocal licensing
agreement
American Superconductor 55 filament
(B2223) tape
Sumitomo (B2223) tape
AMSC B2223 Manufacturing Plant
 Larger billets, Process automation, Longer
strands, Multi-dies, Faster line-speed,
Combination of process steps
 Began volume production in early 2003
 Full capacity could be 20,000 km/year, now
900 km/year
(B2223) Critical Currents 2001-02
Manufacturing variability
32
30
28
> 150 m lengths
Manufacturing Campaign for Detroit Edison
Manufacturing Campaign for Customer X (2002)
26
24
22
Frequency
20
18
16
14
12
10
8
6
4
2
0
End to End Critical Current, Amps
170 A also demonstrated in short lengths
B2223 Wire Improvement
21
20
Jc (A/cm2, 77 K, 0.1T, //c)
19
Measured
MeasuredatatAMSC
AMSCand
& UW
University
UniversityofofWisconsin
Wisconsin
18
17
16
15
14
13
12
1994
1995 1996
1997
1998
1999
2000
2001 2002
 Jc of 19.8kA/cm2 (77K, 0.1T, //c): a new level of performance for wire
with production architecture
 Measurement in 0.1 T field avoids self-field current suppression
Current Distributions in B2223
180 kA/cm2 Regions Observed in AMSC Monocore Tapes
Headroom for Further Current Density Progress
(U. Wisconsin/AMSC)
AMSC B2223 Plant History
• Development started in summer 1988
• 10 years (1998):
•
AMSC produces 20 km in 200 m lengths with
an average current of 90 A at 77 K
• 14 years: 900km/y plant fully operational
• 15 years: 900km/y plant & B2223 IPR
value of $22m written off !
Price/Performance $/kA.m
• How much does it cost to buy the wire to carry
1000 Amps a distance of 1m?
• Copper: 6 $/kA.m – 22 $/kA.m depending on
current density (400 – 100 A/cm2)
• Superconductors typically quoted at Jc and at 77K
and either zero magnetic field or “self field”.
• Cryogenic OFHC copper can be 0.06 $/kA.m.
• NbTi is approx. 0.9 $/kA.m in liquid helium.
Price/Performance $/kA.m
Price/Performance Ratio, $/kA-m
1200
$/kA.m
1000
800
600
World’s First HTS Wire
Manufacturing Plant
Opened By AMSC
400
200
0
1995
200 $/kA.m
1996
1997
1998
1999
2000
2001
2002
2003
2004
Reduced Manufacturing Costs ($/m) and Increased Wire
Performance (current carrying capacity)
B2223 & Commercial Products
• At $50/kAm (77K) price/performance ratio
significant markets would be enabled (it was
thought in ~1999):
−
−
−
−
−
Utility Generators (>100MVA)
Ship Propulsion Motors and Generators (>5MW)
Wind Turbine Generators (>4MW)
Urban T&D Power Cables
Industrial Magnetic Processing
Bought and shut down
by AMSC in 2002
• Significant worldwide industry in B2223
American Superconductor, Innova, Nordic Superconductor,
Sumitomo Electric, Vacuumschmelze, Trithor
Magnetic Field
• High magnetic field reduces current
carrying capacity
• Lower temperatures enhance current
carrying capacity
• B2223 must operate 20K – 40K for motors
which have fields ~ 2T
• B2223 at 27K carries twice the current, so
$/kA.m reduces to 100 $/kA.m.
Saturation in Fe-3%Si at 1.6T
Flux Density, B (T)
1.6
MA/cm2
Peter Lee’s Cosmic Plot (UW/ASC)
10
1.6T
1
0.1
0.01
0.001
Power Apps
30 – 77 K
Copper: up to 400 A/cm2
Key issues for power applications
• Overall current density • Cost!
Je of conductor, not
just of superconductor
• Performance in field
• Multiple filaments for
AC applications
• Anisotropy of Jc with
respect to field
direction
• Conductor itself
• Cooling (AC losses)
• Scalability of
fabrication
• Mechanical
• Strength, bend radius
• Conductor shape
• tape or wire
• or new motor designs
Diboride & YBCO
• YBCO and similar compounds have had
research worth $$billions devoted to their
physics and processing.
• MgB2 was discovered in January 2001;
physics now entirely understood.
• Both can be made in:
• Tape geometry
• Massive lumps for new motor designs
Magnesium Diboride
Mg
B
Mg
B
s
Mg
B
Mg
39K
p
Magnesium Diboride
~ 400 $/kg
Making Diboride tape
Tube filling with MgB2
reacted powders
Wire drawing
and/or rolling
Flat rolling
Long lengths can
be now fabricated
Cu-sheathed tape
transverse cross irregular cross section
section
Simple sintering ~700C
PIT Processing routes for the fabrication of MgB2 wires
B
a)
Mg
+
MgB2
IN-SITU
EX-SITU
b)
tube filling
draw to wire
reaction sintering
IN-SITU
23% porosity
EX-SITU
simple sintering
100m lengths of tape
Powder in Tube
Swege
F = 3.85 mm
P. I. T.
Fin= 5 mm
Ball milling under Ar
Fout= 8 mm
P.I.T.
MgB2
Flat rolling
Tape 4 x 0.38
mm2
Draw
F = 2 mm
Final Tape
Flat
rolling
Université de Genève
HyperTech CTFF for MgB2
CONTINUOUS TUBE FORMING AND FILLING (CTFF)
Irreversibility field
• Increase magnetic
field capability by
metallurgy
• Create pinning defects
by controlled alloying
of MgB2
L. Cowey et al., MgB2 + yttria
Texas Center for Superconductivity and Advanced Materials
University of Houston
NASA Commercial Space Center
TCSAM
10-Meter Long Square MgB2 Wire
Modified
Walters
Spiral
(WASP)
Strain gauges
MgB2
Tape
Ic (A)
Strain Effect on MgB2 long tape 100 h ball milled
70
65
60
55
7T
50
45
40
35
30
25
9T
20
15
10
5
0
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40
strain (%)
d=26 cm
Université de Genève
In situ B+Mg with Fe barrier in Monel Sheath
With iron –tough to make multifilament- most likely be cabled ,
(twisted) monofilaments for low AC loss conductor, working on
Outer sheaths of Monel, Cu/Ni, and Cu to improve stabilization.
Hyper Tech Research
Reasonable properties can be obtained with all Cu wires,
Or with with Nb barriers in Cu.
Multifilament wires can be made
Hyper Tech Research
Shows ITER barrel wound with over 1 meter of MgB2 wire,
all Cu sheath, 1.00 mm diameter wire.
The self field transport current for the coil at 4.2 K was 450 amps,
the estimated transport current at 20 K would be 150-180 amps.
Hyper Tech Research
First test of an MgB2 pancake
BSCCO
Critical Current [A]
250
MgB2 pancake
BSCCO pancake
200
150
4.2 K
100
50
0
3.0
MgB2
3.5
4.0
Magnetic Field [T]
4.5
5.0
MA/cm2
Peter Lee’s Cosmic Plot (UW/ASC)
10
1
Genoa
25 K
0.1
0.01
0.001
Power Apps
30 – 77 K
Magnesium Diboride (MgB2 )
• Advantages
• No weak-link effects, low anisotropy
• Easy to fabricate wires, films: <$10/kA.m potential
• Challenges
• Tc < 40 K (77 K applications like cables, transformers not
viable)
• High field applications such as NMR not viable
• Possible applications in 20-30K range for modest
field environments, e. g., rotating machinery
YBCO Coated Conductor
• Rolled, textured Nickel tape (Ni-W)
• Oxide buffer layer, preserves texture
• YBCO (or analogue, e.g. HoBCO), preserves texture
• Near “single crystal” 100s of metres long
• <$10/kA.m potential
YBCO Coated Conductor
Sumitomo YBCO-CC
YBCO
Ni tape
Oxide buffer
layer deposition
YBCO
YBCO
precursor
YBCO
oxygenation
and conversion
YBCO
Slitting
YBCO Coated Conductor tape
• Active programs in US, Japan and Europe
• Examples of results in 2001:
•
122 A (75 K) over 1 m by LANL
− World record for meter length
•
50 A over 10 m by Fujikura
− World record for 10 meter length
•
Over 60 m :Fujikura
− World’s longest processed tape
Comparative Development
• YBCO CC
• Fujikura announces YSZ-IBAD process, early 1991
• Ten years later (2001):
• Fujikura produces 10 m with 50 A (77 K)
• B2223
• Work started in summer 1988
• Ten years later (1998):
• AMSC produces 20 km at minimum 200 m piece length with an
average current of 90 A (engineering current density 11,000
A/cm2 at 77 K)
YBCO CC Technical Issues
• Adequate uniformity over length
• Stability to over-currents or cracks
• Adequate current in MOD films
• Mechanical properties – spalling, cracking
• Stability of metal-oxide epitaxial interface
• Deposition rate for ion beam and laser processes
• Thicker than 3 micron YBCO ?
• …but must have that 10 $/kA.m process!
B2223 (1G) to YBCO (2G)
Price/Performance $/kA.m
Price/Performance Ratio, $/kA-m
1200
$/kA.m
1000
800
600
World’s First HTS Wire
Manufacturing Plant
Opened By AMSC
400
200
0
1995
200 $/kA.m
1996
1997
1998
1999
2000
2001
2002
2003
2004
Reduced Manufacturing Costs ($/m) and Increased Wire
Performance (current carrying capacity)
AMSC 2G Plant
• 25th Sept. 2003
• ORNL award of $2.5m to AMSC to commercialise 2G
process
• 1st October 2003
• First tranche of $10m from US DoD and DOE to build
2G plant for YBCO-CC tape over 3 years.
• 3rd October 2003
• $44m share issue priced to be used to build 2G plant
• but all committed on pre-commercial processes!
Performance
Technology ‘S’ Curves
Effort
Power Technologies
HTS g2
17y
MgB2
Performance
75y
HTS g1
Copper-Iron
2003
Effort
Conclusions:
Superconductors for Motors
• HTS G1:
• B2223 tape
• Diboride:
• MgB2 wire
• MgB2 HIPped bars
• HTS G2:
• YBCO CC tape
• YBCO cast crystals