A5032925323- Superconducting Materials and Applications
- Physics of Superconductivity and Magnetism
- Magnetic confinement fusion research
- HVDC Systems and Fault Protection
- Fusion materials and technologies
- High voltage insulation and dielectric phenomena
- Particle accelerators and beam dynamics
- Spacecraft and Cryogenic Technologies
- Plasma Diagnostics and Applications
- Concrete Corrosion and Durability
- Electrical Fault Detection and Protection
- Thermal Analysis in Power Transmission
- Graphite, nuclear technology, radiation studies
- Magnetic and transport properties of perovskites and related materials
- Dielectric materials and actuators
- Lightning and Electromagnetic Phenomena
- Integrated Circuits and Semiconductor Failure Analysis
- Electrical Contact Performance and Analysis
- Frequency Control in Power Systems
- Power Line Inspection Robots
- High-Voltage Power Transmission Systems
- Organic Light-Emitting Diodes Research
- Magnetic Field Sensors Techniques
- Superconductivity in MgB2 and Alloys
- Magnetic Properties and Applications
Oak Ridge National Laboratory
2015-2025
National Transportation Research Center
2016
National Institute of Standards and Technology
2010
University of Colorado Boulder
2010
Rockwell Automation (United States)
2007
Oak Ridge Associated Universities
2003
University of Wisconsin–Madison
2001-2002
The availability of future fusion devices, such as a nuclear science facility or demonstration power station, greatly depends on long operating lifetimes plasma facing components in their divertors. ORNL is designing the Material Plasma Exposure eXperiment (MPEX), superconducting magnet, steady-state device to address material interactions reactors. MPEX will utilize new highintensity source concept based RF technology. This allow experiment cover entire expected conditions divertor reactor....
Linear plasma generators are cost effective facilities to simulate divertor conditions of present and future fusion reactors. They used address important R&D gaps in the science material interactions towards viable facing components for Next generation have be able access expected on targets ITER devices. The steady-state linear device MPEX will this regime with electron temperatures 1–10 eV densities . resulting heat fluxes about 10 MW is designed deliver those a novel Radio Frequency...
Thermal stability and quench propagation in a composite tape made of YBa/sub 2/Cu/sub 3/O/sub x/ (YBCO) superconductor were studied experimentally. Quench each test was initiated by applying sequence short overcurrent pulse followed longer at typical operating current for the tape. The resulting change resistivity due to internal heating measured through voltage taps across different zones Measurements performed as function both initial several temperatures between 45 80 K. These...
Transport alternating current (ac) loss measurements were performed on a series of rolling-assisted biaxially textured substrate (RABiTS) processed YBa2Cu3Ox (YBCO) coated conductors at 77 K. While each sample possessed 1 µm layer YBCO and 3 silver cap layer, two different nickel alloy substrates used their impact the ac was examined. Both 75 Ni–5 at%W base, but one also had 2 overlayer as part buffer architecture. The losses, which determined by thermal electrical measurements, contained...
In order to predict heat loads in future saturable-core fault-current-limiting devices due ac fringing fields, dynamic resistance YBCO-coated conductors was measured at 77 K peak fields up 25 mT 60 Hz and dc 1 T. With the sample orientation set such that conductor face either parallel or perpendicular applied different fractions of critical current determine relationship between transport fields. respect field orientation, for were significantly higher than when face. It also observed...
General Electric proposes to apply transformational technology in the form of low-temperature superconductivity design direct-drive wind turbine generators 10-MW power level and greater. Generally, optimal steady state 4 K cryogenic cooling a large thermal mass (> 10 000 kg) its dimensions m diameter 2.5 length) with minimum levelized cost energy is difficult achieve. A strategy has been found that turns this size disadvantage ones favor, furthermore enables scalability field winding...
In support of second generation HTS conductor development for ac applications, transport loss measurements were conducted on a series RABiTS-processed YBa/sub 2/Cu/sub 3/O/sub x/ (YBCO) coated conductors with different nickel alloy substrates and copper stabilization at 77 K. Each 1-cm wide sample had critical current density between 1.0 2.0 MA/cm/sup 2/ either 75 /spl mu/m Ni-5at%W substrate or Ni-10%Cr-2%W 2-/spl overlayer. Samples 50-/spl strip 1 cm laminated to 3-/spl thick silver YBCO...
In the current study we focus on dielectric properties (as a function of frequency and temperature) polymeric composite system composed polyvinyl alcohol barium titanate nano powder. investigations, temperature range is between 50-295 K, 20 Hz-1 MHz. Polarization conduction processes are investigated in linear regime. Dielectric breakdown strengths samples also reported. The materials presented have potential to be implemented cryogenic capacitor or field grading applications.
Recent successes in demonstrating high temperature superconducting (HTS) cable systems hundreds of meters length have inspired even longer projects. A compact and energy efficient cooling configuration can be achieved using a counterflow-cooling arrangement. This is particularly attractive when all three phases are contained single cryostat because the elimination space thermal requirements separate liquid nitrogen return line. Future projects will utilize second generation (2G) wire which...
The Ultera/ORNL team have built and tested 3-m 5-m triaxial cables rated at 3 1.3 kA-rms, respectively. three concentric superconducting phases are made of BSCCO-2223 HTS tapes, separated by layers cold-dielectric tapes. A copper braid is added as the grounding shield on outside active phases. Tests these were performed temperatures ranging from 70 to 84 K. AC loss data reconfirmed previous result a 1.5-m prototype cable that total 3-phase ac about sum calculated losses These other test...
High-temperature superconducting (HTS) transmission cables are subjected to short-circuit fault currents 10 30 times the normal operating current and lasting up 15 cycles. These over-currents will drive HTS conductor generate heat during fault. A concern is whether either electromechanically or thermally damage degrade it burn-out tape altogether. Electromechanical thermal limitations of over-current pulses were measured on BSCCO YBCO tapes in a liquid nitrogen bath. With pulse lengths as...
The Materials Plasma Exposure eXperiment (MPEX) is a linear plasma device that will address the plasma-material interaction (PMI) science for future fusion reactors and enable testing of plasma-facing components (PFCs). It designed as steady-state eventually delivering an ion fluence up to 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sup> m xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> target. be handle neutron-activated...
To achieve low ac losses in applied fields, YBa <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Cu xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> (YBCO) filaments were created on a RABiTS buffered substrate through solution inkjet deposition. A metal organic decomposition (MOD) was placed into an dispenser and of widths 100 mum 0.8 mm deposited the at spacing 50 to mum. Each...
Cryogenic pellet injectors for use in fusion research have been under development at Oak Ridge National Laboratory over 30 years. The original application of the technology was to add fuel magnetically confined plasmas replace D-T ions that are consumed reactions or lost due transport out confining magnetic fields. This is still primary injection and planned implementation on ITER burning plasma experiment. More recently, there additional applications cryogenic pellets areas disruption...
A pair of silver coated YBCO tapes with varying degrees electrical contact between the and nickel substrate were studied to examine impact on normal zone formation stability. The fabricated using rolling assisted bi-axially textured (RABiTS) method 15-cm-long samples 2 /spl mu/m prepared. place in a conduction cooling environment at 45 K study quench or recovery when series dc transient over-current pulses applied. We used voltage taps both characterize nature through measured voltages. In...
The Material Plasma Exposure eXperiment (MPEX) has completed its design phase. MPEX will be a unique facility to investigate plasma material interactions (PMIs) under fusion prototypic divertor conditions in steady state. This includes exposure expected reactor divertor. Materials investigated include solids, liquids, and neutron pre-irradiated materials. Electron ion heating allow for large operational domain ranging from erosion-dominated PMI deposition-dominated conditions. An overview of...
Significant technology maturation efforts are underway by privately funded fusion startups with the goal to demonstrate mature HTS magnet technology. To support private sector development effort and DOE milestone based program, a U.S. Fusion Magnet Community Workshop was held on March 14-15, 2023 in Princeton, NJ. This first community workshop focused technologies aimed at determining structure technical direction for public program designed complement industry landscape. Based wide range of...
An investigation of the current distribution in a three-phase triaxial superconducting cable is underway to study phase imbalances under steady-state operation and assist construction transient model operational impacts power grid. The consists three concentric phases inside copper shield, with each composed multiple layers BSCCO tape wound helically opposite directions. Current among determined by using an electric circuit (EC) containing self mutual inductances resulting from both axial...
With recommendations from wire manufacturers as a starting point, series of solder joints were fabricated and characterized to determine the best method for producing repeatable, low‐resistance high‐mechanical‐strength splices in as‐manufactured, stabilized YBCO coated conductors. From 2.54 cm long splice that fabricated, parameters such material, stabilization fabrication method, conductor geometry varied impact each on properties joints. Results indicate lowest resistance influenced...
Two 3-m long, single-phase cables have been fabricated by Ultera from second generation (2G) superconductor wire supplied American Superconductor. The first cable was made with two layers of 2G tape conductor and had a critical current 5,750 A while the four 8,500 A. AC loss measured for both at ac currents up to 4 kA <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</sub> . performed initial fault studies in Denmark limited range 9.1 44 kA....