HTS bulks for magnetic application

Transcription

1 HTS bulks for magnetic application F. N. Werfel, U. Floegel- Delor, T. Riedel, D. Wippich, B. Goebel, R. Rothfeld, P. Schirrmeister Adelwitz Technologiezentrum GmbH (ATZ), Naundorfer Str. 29, Torgau, Germany The work was supported by the German BMBF /VDI under 13N8737; by the German Federal Ministry of Commerce and Technology (BMWi) under B

2 An effective cooperation is acknowledged: L-3 Communications Magnet Motor, Starnberg INA Schaeffler, Schweinfurt ; EADS /Astrium Bremen; THEVA Ismaning, Bruker HTS, Alzenau, AIM Heilbronn, Leybold Dresden Decker Anlagenbau, Berching EVICO +IFW Dresden KIT, Karlsruhe, U Augsburg, MPI Stuttgart A special thank Thermo Fisher Osterode is addressed to SuperPower, USA; CERN Geneva Dr. Zigang Deng, DSTO Australia, CNRS Orsay Univ. Rio de Janeiro UFRJ, Brazil Southwest Jiaotong University, ASCLab, Chengdu, CN Tokyo University of Marine Science and Technology, JP Beijing Milestone, CN Universities: Geneva, Paris, Cambridge, deliege, de Vigo, Madrid, Stellenbosch, Barcelona Minnesota, Cleveland, Houston, Cardiff, Nancy, Lisboa, ETH Zurich, Wollongong, SEMECCEL Toulouse

3 Overview 1. Introduction 2. High-T c superconductors 3. Melt textured REBCO fabrication 4. Characterization of bulk samples 5. Magnetic applications of HTS bulks Magnetic bearings Flywheel Energy Storage System Transportation 6. Conclusions and Outlook

4 1. Introduction Adelwitz Technologiezentrum GmbH (ATZ); ATZ Corp. founded in 1992, in Adelwitz-Arzberg, Germany wide spectrum of High - Tc superconducting materials and innovative components in house production ~0.9 ton /a HTS material (REBCO powders, mt bulks, targets, thin film) fabrication of about 130 HTS magnetic systems (HTS bearings up to ton loads, MAGLEV, cryostats, PM bearing systems) economy and flexibility in HTS fabrication & application; preindustrial technologies (powder, bulk, conductor elements) 2013: ATZ moves into a new and larger Company location Torgau

5 HTS Bulk Material powders, targets, melt textured blocks Components & Devices HTS magnetic couplers and bearings

6 Bulk material results REBCO large single grain materials Parameter: Jc = ka/cm² (SF, 77K) T trapped field at 77 K 17.2 T at 29 K (Murakami, Nature 421, (2003) 16.4 T at 24 K (Fuchs & Krabbes et.al (2002) REBCO materials RE: Nd, Sm, Eu, Gd (Oxygen controlled melt Growth Method)

7 Background REBCO bulk: Levitation and trapped field 3 T@77 K 11 T@47 K B trap AJ r c F J B dv lev ex

8 ReBa2Cu3O7-δ (RE123) crystalline structure RE= Y, Sm, Gd, Dy, Nd, High Tc Superconductors SmFeAsO1-xFx Tc max 55.3 K

9 B J B Flux free region: B = 0 Flux penetrated region: J = J c = const Cylinder: JJc The Bean model B a B a a R J c r Thin disk: B a B a a R r

10 BEAN Model Bean (1962) and London(1963) introduced the concept of the critical state in which the current in a type II superconductor flow either at + Jc, -Jc or zero. Critical State is a static force balance between the magnetic driving force JxB and the pinning force Fp (B x ( x H)) = BJc(B) Solutions define the macroscopic current distribution and enable the Jc to be determined from magnetization measurement

11 2. Melt textured REBCO fabrication T 1055 C/ 0.75 h 1005 C 940 C/4h C/h Time /h YBCO OD 45 x YBCO 3-seed bulks 65 mm x 32 mm x 13 mm, 3 seeds

12 Large- scale GdBCO Bulk: 150 mm Ref. Courtesy H. Teshima and M. Morita, Nippon Steel Corp.

13 Multi- seed fabrication Top seeding melt texture procedure (TSMG) Isostatical pressure compacting process CIP (1 1.5 kbar) up to 250 mm diameter cold seeded by SmBCO seed crystals recycling of the seeds (partly) exact lateral orientation of the seeds 3-seed samples 67 x 34 x 15 preferred (large numbers) Sizes Dia mm, 15 mm thickness, single grain 67 mm x 35 mm x 14 mm, 2-3 seeds 90 mm x 60 mm x 20 mm, up to 8 seeds Magnetic force (77 K): N at 0.5 mm against 25 mm SmCo, 0.4 Tesla Trapped field (77 K): Tesla@B 0 = 1. 4 Tesla (77K)

14 High Tc YBCO bulk crystals x 60, 8 seeds 46 x x 34, 3 seeds

15 Doping strategy Zn Ref. G. Fuchs, G. Krabbes et. al., Physica C (2002)

16 Recent doping results of GdBCO bulk HTS B max = 1.37 T B max =1.05 T Ref. M. Miki, 2, B. Felder, K.Tsuzuki, Y. Xu, Z. Deng, M. Izumi, H. Hayakawa, M. Morita and H. Teshima, SUST23(2010) Doping with 0.4 mol% Fe-B-Si-Nb-Cr-Cu (MP)

17 Bulk machining and treatment -Cutting using diamond tools -Numerical machining -Surface stabilization; resin impregnation, Cu impregnation -Copper surface depositon -Recycling bulks -Recycling seeds -Mechanical bolt -Bulk thinning

18 Magnetization of bulk superconductors Field Cooling (FC) Zero Field Cooling (ZFC) Pulsed Field Magnetization (PFM) Flux pumping Hochfeldlabor Dresden / up to 100 T / 10 ms, V + Condensor - Bank C R L B(T) max. pulse field rise time: t (ms)

19 Ref. T. Oka, H. Ikuta et.al. Physica C 335 (2000) p

20 3. Bulk YBCO characterization 3 a) Magnetization 3 b) Local trapped field analysis

21 mm B T (T) B peak : 0.34 T, 0.33 T and 0.31 T B valley : T Φ: 0.38 mwb the estimated trapped flux peak (0.34 T at 4 mm gap) at 1 mm gap was 0.60 T, which was about 91% of that obtained by static FCM. PFM method is effective for multi-seeded bulk (90% performance compared with static FCM results Y (mm) B T (T) 30 X (mm) X (mm) Y (mm) 4 mm B T (T) Z. Deng et al, IEEE Trans.Appl. Supercond. 2011, to be published 21

22 force after cutting [g] Integral trapped field estimation fast approach Reduced magnetic forces after machine cutting the bulks B trap / B F attractive bulk HTS F original 6 weight % reduced material 0.94 F original Fe 1600 F experimental F attr. after border cut much smaller force than F attr. (as-grown) - 6% (material loss) force after as grown [g]

23 Trapped flux: single grain

24 mt MT YBCO 8-seed, B exc = 0.75 T

25 Trapped flux density (T) Bulk-cutting Zone A Zone B Multi-seeded bulk Combined bulks Distance (mm) T and T VS T and T / = 66.7% / = 48.4% intra-grain super current B peak : T Φ: mwb > 40% B peak : T Φ: mwb inter-grain super current

26 Jc (B) measurements (Nd0.33Eu0.33Gd0.33)Ba2Cu3Oy+35 mol % Gd2BaCuO5 (70 nm in size) composite doped amounts of nanometer-sized MoO3 or NbO3 particles. (10 nm) At 65 K: 700 ka/cm2 with Mo and 925 ka/cm2 with Nb at both 0 and 4.5 T, self-field current at 90 K was 100 A/cm2 in the Nbdoped sample, Appl. Phys. Lett. 92, (2008); Record flux pinning in melt-textured NEG-123 doped by Mo and Nb nanoparticles M. Muralidhar1, N. Sakai2, M. Jirsa2, M. Murakami3, and I. Hirabayashi1

27 Trapped field (T) Trapped field relaxation ratio(%) Trapped field (T) Low temperature trapped field measurements mm gap 77K 72K 61K 50K 41K 30K Trapped field improvement in lower temperatures Three-seed bulk YBCO Distance (mm) In LN2 gap of 1 mm gap of 4 mm Temperature (K) relaxation ratio at different temperatures Measurements by M. Izumi & Z. Deng at TUMSAT G-M cryocooler, cooling power 76W@30K; 5 T LTS magnet system;

28 5. Magnetic applications of HTS bulks Magnetic bearings Flywheel energy storage Transportation

29 magnet above HTS stable position force opposite to shift B position change magnetic forces JxB J induced supercurrents field change on HTS

30 Magnetic bearings Active magnetic bearing AMB Superconducting magnetic bearing SMB Electromagnet Rotor Sensor Controller Amplifier persistent currents permanent magnet M Lorentz force j x B superconductor 1) Magnet Force density field energy µ 0 H²/2 Nd-B-Fe, highest BH-product 2) Superconductor - zero resistance + loss up to critical current density j c n - n= E j) E ( j / ) ( 0 j c AMB; Source: SKF - high current densities A/cm 2

31 High-gradient bulk HTS bearing Shaft Cu cylinder r z L PM rings Fe flux collector YBCO bulk Magnetic gap B B r z r sin z / L B( 0) exp( )... L cos z / L B(r,z) excitation w. HTS Field gradient: radial stiffness df r /dr 1/L Field varies axially: shift induces currents df z /dz 1/L

32 Force generation by displacement PM rotor 4 mm Fe force YBCO force 2 mm stiffness

33 Engineering work: 2 ton glass fiber platform, Q = 0.26 W@200 K T 1-ton flywheel HTS bearing G/M Cooler cold head thermal coupling, flexible Cold head, thermal coupling, flexibel radial support Radial bearing housing Fabricated bearing Cu ring + YBCO Cu ring + YBCO Bearing design PM rings, PM stacked

34 force [N] Bearing forces and stiffnesses 200 mm HTS bearing mm HTS magnetic bearing force dependence of temperature and PM / Fe configuration pole pitch [mm] 72 K displacement [mm] Parameter: Temperature and PM configuration 79 K 20, 72K 22, 72K 18, 72K 20, 79K 22, 79K 17, 79K 18, 79K Design /Geometry, Diameter x height [mm] Superconductor Magnetic gap Free rotor movement [mm] Maximum load, radially [N] Maximum load, axially [N] Stiffness, radially [kn/mm] Rad stiffness ymmetry Stiffness axially [kn/mm] Thermal losses [W] Rotational friction [Nm] Radial type, 205 x 120 Melt textured YBCO, 3 seeds 2.5 mm 2 mm radial 4700 at 3.2 mm displacement 72 K! 4600 / 1 mm, /3.3 mm 1.8 (72 K ), 1.4 (79 K) Radially homogenously 4.5 (72 K), 3 (78.5 K) < 20 W - 5 x 10-4

35 Technical and cost comparision for replacement mechanical bearings of a 2-3 MW steam generator Mechanical AMB HTS force [kn] 6.5 / 30 peak >10 10 max. rpm 10 k 10 k >10 k loss [kw] periphery oil cooler, filter electronics cryo-cooler 5 kw 2x 130W/6.5 kw invest [k$] operational costs /year [k$] maintenance large-scale low low *Data are obtained a by large-scale power machine supplier.

36 5. HTS magnetic application Flywheel Energy Storage System

37 Boeing flywheel energy storage system with critical components Ref. Strasik M, et al.

38 Figure. NEDO test flywheel energy storage system with composite rotor Ref. Koshizuka N (2010) The superconducting magnetic bearings and magnetic clutches for flywheel energy storage, PASREG 10, Washington

39 10kWh/250 kw Flywheel with HTS Bearing CFRP Rotor HTS bearing Power electronics YBCO bulks Magnet excitation system

40 Table R&D development costs of HTS flywheels (approached) Institution / Project [million US $] Boeing, USA ~ 20 NEDO consort., JP ~ 35 Nexans, Piller, GER ~ 10 Kepri project, KR ~ 14 ATZ/MM, GER ~2.3 NEDO, LTS, JP ~ 25 Most of the project costs are system costs not superconductor!

41 Homogenizing renewable energies (wind, solar, hydrogen) FESS coupling with solar tiles and windmill generators, provides, adequate power generation and storage capability reaches maximum energy capacity maximizes their energy yields frequency and voltage regulation prevents dc line over-voltage step change wear and tear on gear boxes is minimized wide operating range power compensation grid stability switchgear 50Hz Power Inverter Variable voltage Regulator Regulator & rectifier Variable voltage & frequency FESS Controller DC LOADS FESS AC LOADS

42 HTS bulk application: Magnetic coupling

43 Wafer coupling system, not bearing PM HTS magnetic coupler for semiconductor wafer treatment Rotational HTS vacuum cryostat of magnetic coupler; diameter: 350 mm, LN 2 cooling

44 Magnetic bulk application: Axial motors and generators Ref. M. Miki, 2, B. Felder, K.Tsuzuki1, Y. Xu, Z. Deng, M. Izumi1, H. Hayakawa, M. Morita and H. Teshima, SUST 23, 2010,

45 Further magnetic applications of REBCO bulk Fig. Cross section of mouse embryo measured using MR microscope Appl. Phys. Lett. 98, (2011); Development of a magnetic resonance microscope using a high T c bulk superconducting magnet Kyohei Ogawa 1, Takashi Nakamura 2, Yasuhiko Terada 1, Katsumi Kose 1, and Tomoyuki Haishi

46 Transportation

47 Maglev Cryostat Vacuum cryostat/st.steel Cu /YBCO HTS 2 x 12 YBCO blocks Cooling LN 2, Operation time > 24 h Cryostat weight ~ 17 kg Magn. Distance Levitation 2 mm distance bottom YBCO ~ mm; g = magnetic gap Force density 5N / cm² 0.65 x h 1.5 x g 0.9 x g p = 6 x g Fe PM 47

48 MAGLEV cryostat Vacuum connection Mechanical support G- 10 plate Stainless Steel LN2 filling tube LN2 Bulk HTS TABLE: VACUUM CRYOSTAT/ST.STEEL /Cu /YBCO Geometry 440 x 180x 120 YBCO bulks 2 x 12, size (64 x 32 x 13) HTS area 492 cm² Cooling LN 2, storage 2.5 l Operat. time h, static Cryostat weight ~ 17 kg Magn. Distance 2 mm, distance bottom YBCO Levitation ~ 2500 mm; fc30 ~4000 N@5 mm Halbach PM Force density 5 N/cm², 8 N/cm² (Halbach)

49 Production of a small series of cryostats (35 pieces)

50 Linear MAGLEV- Cobra, U Rio de Janeiro Full-Scale Module of the Maglev-Cobra HTS-Superconducting Vehicle, U. Rio de Janeiro; MAGLEV HTS cryostats fabricated by ATZ Levitation force of one MAGLEV cryostat at different field -cooled positions Ref. Sotelo G G. et al. (2011) Tests on a superconductor linear magnetic bearing of a fullscale Maglev vehicle, IEEE Trans. Appl. Supercond. 21,

51 Vacuum cryostat/st.steel/ Cu /YBCO Maglev cryostat HTS Cooling Operat. time Cryostat weight Magn. Distance Levitation Force density 2 x 12 YBCO blocks LN 2, 2.5 l > 24 h ~ 16 kg 2 mm distance bottom YBCO ~ mm; fc35 5N / cm² U Jiaotong Chengdu, CN Supratrans II, IFW Dresden

52 Supratrans II, Dresden

53 6. Conclusions and Outlook Excellent HTS RE bulk materials are available today at comparable costs of RE magnets HTS bulk can enter the magnet market up to 5 T easily by small robust and reliable systems. The technical performance and feasibility of HTS bulk magnetic devices in energy technique and mechanical engineering has been successfully proven. In the first market phase the investment costs are higher than those of conventional technique. Competitiveness will obtained due to the lower operational and maintenance effort with time.

54 Stabilizing the atmospheric CO 2 concentration at 450 ppm Restriction the global mean temperature rise to 2 Kelvin in the 21 century (0.2 K per decade) Global primary energy demand not more than double by the end of this century (from 400 to 800 EJ) Share of fossil fuels should drop to 25 % by 2100 Three key elements Solution and Rewards - substitution of fossile fuels by CO 2 free energies - efficiency increase (Research infrastructure) - demand side management HTS Europe, US and Japan can be the most efficient energy regions of the world.