The Superconducting Test Facility at ASIPP and Its Next Plan

1. The Superconducting Test Facility at ASIPP and Its Next Plan H.J. Liu & testing team Institute of Plasma Physics, Chinese Academy of Sciences *liuhj@ipp.ac.cn

2. Outlines • Introduction • Superconducting materials testing • Testing for large-scale conductor • Test facility for magnets • Next Plans for Testing Facility • Conclusion

3. Introduction Prototype power station Engineering reactor 1GW, parallel in grid Experimental reactor Phase 1(Engineering verification)Steady, Q=1.5, 200MW, 10dpa Phase 11(Demostration verification)Steady, Q>10, 1GW, 50dpa Phase 1：Q=10, 400s, 500MW, D-T combustion plasma Phase 11：Q=5，3000s，350WA，Long pulse combustion plasma Steady Advanced divertor, and steady high confined plasma Advanced divertor and high power heater Breakdown control and basic plasma

4. Introduction Engineering Requirement CFETR magnet system 低温：-269℃ 强场：11.8T 应力：800kN/m • Physics Target • Fusion Power: 200-1500 MW • Duty Time: > 0.5 • Tritium Breeding Ratio: > 1 F B

5. Introduction Nb3Sn, Bi2212 and YBCO - promising materials for CFETR coil Peter Lee • High values of Jc, Tc, Hc2 • Round wire, possibility of cabling • Twisted, multifilament, isotropic, low loss conductor with high RRR We need to develop the facility for critical current measurement (or Tcs) of superconducting wires, conductors and magnets, especially for Bi2212 and YBCO large-scale conductor.

6. Superconducting materials testing • DC critical Current test (IC) at variable T and Field • Magnetic field: 14.3T • Temperature: 4.2-80K • Temperature Accuracy • 10mK (4.2-10K) • 50mK (10-30K) • 120mK(30-80K) • Imax = 2kA/4.2K • Imax = 800A/variable T Magnet Specifications • Through bore: 70.0mm • Highest Field: 14.3 T@4.2K

7. Superconducting materials testing • DC critical Current test (IC) at variable T and δ • Magnetic field: 14.3T • Temperature: 4.2-8K • Temperature Accuracy: 10mK • Strain: -1%1% • Strain homogeneity: 98% *Cooperated with Twente University

8. Superconducting materials testing

9. Superconducting materials testing • RRR Value (273K/4.2、10K or 20K) • Temperature Accuracy: <100mK ice-water mixture RRR sample T sensors ITER superconducting wire NbTi : ρ10K/ρ273K Nb3Sn: ρ20K/ρ273K

10. Superconducting materials testing AC losses tests (hysteresis & coupling) 4.2K Hys sample

11. Superconducting materials testing • Stress-strain tests • RT • 77K • 4.2K • εYield=0.3%@RT; • εYield=0.4%@77K; • E=517GPa@RT • E=1125GPa@77K

12. Superconducting materials testing • RT testing • Strand diameter • Plating thickness • Twist Pitch • Cu/non-Cu Ration • Thickness • the thickness of the Cr layer was measured with the optical microscope or scanning electron microscope (SEM) at six locations, at 60° each, with an accuracy better than 0.1µm. • The average Plating thickness is 1.77µm. • Twist Pitch • The test procedure was : • Fix the sample with a holder; • measure the etching length L; • Rotate, record turns n. • Test result is 14.9mm a) • Diameter • By metallographic Photo: 0.7324mm • By Micrometer: 0.732mm b) c) • Cu/Non-Cu • The Cu ratios were measure by chemical etching and weighing, then calculate. d)

13. Testing for large-scale conductor • Testing facility 1 • Background Magnetic field: 7.6T • Maximum current: 75kA • SHe mass flow: 50g/s • Temperature: 5K-8K

14. Testing for large-scale conductor • The sample is wound as a half circle. • The short sample and the terminations are individually supplied by supercritical helium at about 5 bar operating pressure. • The inlet temperature is controlled by two heaters and measured by four thermal sensors. • The mass flow rate is controlled by valves after the helium outlet. Mass flow rate, temperature are also measured.

15. Testing for large-scale conductor A length of 25 m of ITER CC conductor was manufactured for two ITER CC conductor short samples, CCCN1 and CCCN2, which have been prepared at ASIPP. Sample CCCN1 was tested in the ASIPP test facility, and sample CCCN2 was sent to Switzerland and tested in the SULTAN facility. ITER CC conductor testing

16. Testing for large-scale conductor • The TCS values of 7.02 and 7.20 K were measured for sample CCCN1 and sample CCCN2, respectively. • at the peak a magnetic field of 4.1 T and at a current of 10 kA. There was a systematic overestimate of the temperature of 0.1 K at the SULTAN laboratory. • The difference in TCS measured at the two facilities was 0.08 K.

17. Testing for large-scale conductor • Test facility 2 • Background Magnetic field: 6.5T • Maximum current: 40kA • Temperature 4.2K Normalized magnetic field Length of uniform field: 400 mm Height (cm) Dipole magnet

18. Testing for large-scale conductor DC power supply 200 A Magnet power supply Background magnet Cryostat 200 A current leads Current leads Test facility 40 kAsuperconducting transformer Power supply system （magnet power supply, 200 A DC power supply, 6 kA & 200 A current leads） Superconducting transformer Data acquisition system Quench detection and protection system Conductor sample Joints Magnet

19. Testing for large-scale conductor integrated G10 fixer Compact with Indium A-A A-A B Terminal for sample Bolting SS support G10 support Terminal for transformer Helium path G10 fixer CC conductor Rutherford cable

20. Testing for large-scale conductor

21. Test facility for magnets • Test facility 1 for magnet • Cryostat: Ф3.1m×H4.2m • Vacuum: <10-3Pa • Maximum Current: 20kA • Refrigerator: 500W@4.5K • Temperature: 4.5K • Mass flow: 30g/s • A large superconducting magnet test facility has been set up at the Institute of Plasma Physics, the Chinese Academy of Sciences since 1999. The primary goal of the test facility is to test the EAST TF and PF magnets performance. This test facility has been completed in 2002. From 2002 to 2005, 29 times TF and PF prototype coils and model coils test have been set up and tested in this test facility.

22. Test facility for magnets • Main testing • helium leakage test at RT and LT • coil cool-down and warm-up • Thermal-hydraulic property • Joint resistance • AC and DC testing • Simulation the operation discharge • Quench detection • sixteen TF magnets, a central solenoid model coil, a central solenoid prototype coil, a model coil of PF large coil, two sets of divertor coils, assembled together six central solenoid coils have been tested in the test facility.

23. Test facility for magnets • Excite the coil with the rate of 1 kA/s up to 15.2 kA and keep the flat top for 20 seconds. • Discharge the coil with dump rate –20 kA/s for 160 ms up to 12kA • Discharge the current from 12 kA to 10.6 kA with dump rate –10 kA/s for 140ms • 10.6 kA to 6.6 kA with dump rate -5 kA/s for 0.8 seconds, -1.5 kA/s to 0. • 0 to –13.2 kA with the ramp rate -1.5 kA/s, keep the flat top for 10 seconds • dump the current up to 0 with rate of 3KA/s again.

24. Thermal shield Feeder Test facility for magnets The cryostat: was installed Vacuum system: vacuum pump was installed and the control system will be installed Supporting platform: was installed 50kA HTS CL and Feeder: ASIPP Feeder team will provide the HTS CL. The Feeder system will be installed in Feb. or Mar. 2019. Thermal shield: The thermal shield is installing and will be tested in this month. • Test facility 2 for magnet • Cryostat: Ф8m×H8m • Vacuum: <10-3Pa • Maximum Current: 50kA • Refrigerator: 900W@4.5K • Temperature: 4.5K • Mass flow: 200g/s Cryostat Vacuum system

25. Next Plans for Testing Facility • Superconducting materials testing • Magnetic field: 19T • Loss research：+/-1.5T • HV research：0-100kV Thermal engineering and fluid mechanics • Scientific objectives：Know well the intrinsic physical properties and engineering behavior of the superconducting materials in complex working condition and environments, and carry out the engineering application research. Nondestructive detection • Elements：64 • Test frequency：0.25MHZ~32MHZ • X-rayMax. voltage：450KV • Amplitude of AC field：+/-1.5 T • Frequency：0.01-0.2 Hz • Test aperture：80 mm x 100 mm • Homogeneity length：550 mm • Max. Load：1500 kN/m • Cycle: 40,000 • Temperature：4.2K-1273K • Static load: ±2500kN • Dynamic load: ±100kN • Test voltage：0-100kV • Pressure: 0.01Pa-10000Pa • Magnetic Field: 19 T • Test temperature: 4.2 K-300 K High voltage Loss and mechanical characteristics Engineering critical performance

26. Next Plans for Testing Facility • Superconducting conducter testing • Magnetic field: 15T • B Homogeneity: 95% • Homogeneity Length: 550mm • Test current: 100kA • Temperature: 4.5-8K • Refrigerator: 2kW@4.5K • Mass flow: 200g/s • Scientific objective：to study the transport current performance of superconducting conductors under multi-field coupling conditions and evaluate the reliability of engineering technology and safe operation.

27. Next Plans for Testing Facility • Superconducting magnet testing • Cryostat: L>18m\W>14m\H>3m • Vacuum: <10-3Pa • Maximum Current: 100kA • Refrigerator: 2000W@4.5K • Pressure: 3-6Bar • Temperature: 4.5K • Temperature accuracy: 0.05K • Mass flow: 500g/s • Provide a research platform for superconducting magnet key performances; • Provide the large cryogenic test platform for Chinese advanced superconducting magnet experiment; • Train Chinese talents for the construction and test operation of the advanced high-field superconducting magnet. • Simulate the operating environment of large- scale magnets; • Carry out the experimental research in mechanics, thermal and electro-magnetic properties; • Evaluate the magnet performances (Safety, stability, reliability).

28. Conclusions • Materials Researches • DC critical Current test (IC) at variable T and Field • DC critical Current test (IC) at variable T and δ • RRR Value (273K/4.2、10K or 20K) • AC losses tests (hysteresis & coupling)4.2K • Stress-strain tests • RT testing (Strand diameter/Plating thickness/Twist Pitch/non-Cu Ration) • Large-scale Superconducting Conductor Testing Facility • Testing facility (The sample should be rounded as a half circle) • Testing facility • Magnet Testing • Magnet testing system with diameter 3m • Magnet testing system with diameter 8m • New Testing Facility Plans • Materials testing with high field • Large-scale conducting test facility with 15T background field • Magnet testing with 20m*14m*3m

29. Thanks！