A5008857883- Physics of Superconductivity and Magnetism
- Superconducting Materials and Applications
- HVDC Systems and Fault Protection
- Superconductivity in MgB2 and Alloys
- Frequency Control in Power Systems
- Advanced Fiber Optic Sensors
- Magnetic and transport properties of perovskites and related materials
- Photonic and Optical Devices
- Magnetic Bearings and Levitation Dynamics
- Electric Motor Design and Analysis
- Magnetic Properties and Applications
- Particle accelerators and beam dynamics
- Spacecraft and Cryogenic Technologies
- Magneto-Optical Properties and Applications
- Gas Sensing Nanomaterials and Sensors
- Magnetic confinement fusion research
- Advanced MEMS and NEMS Technologies
- Advanced Fiber Laser Technologies
- Advanced Thermodynamic Systems and Engines
- Semiconductor Lasers and Optical Devices
- Analytical Chemistry and Sensors
- Mechanical Behavior of Composites
- Silicon Carbide Semiconductor Technologies
- Solar and Space Plasma Dynamics
- Induction Heating and Inverter Technology
Victoria University of Wellington
2016-2025
The Dodd-Walls Centre for Photonic and Quantum Technologies
2024-2025
Changwon National University
2021
Beijing Jiaotong University
2019-2021
University of Edinburgh
2021
University of Birmingham
2005-2016
University of Canterbury
2016
Hutt Hospital
2009-2013
Callaghan Innovation
2010-2013
Cranfield University
2003-2006
Superconducting technology applications in electric machines have long been pursued due to their significant advantages of higher efficiency and power density over conventional technology. However, spite many successful demonstrations, commercial adoption has slow, presumably because the threshold for value versus cost risk not yet crossed. One likely path disruptive superconducting products could be where its become key enablers systems which are practical with To help engineers assess...
Abstract High-temperature superconductors (HTS) promise to revolutionize high-power applications like wind generators, DC power cables, particle accelerators, and fusion energy devices. A practical HTS cable must not degrade under severe mechanical, electrical, thermal conditions; have simple, low-resistance, manufacturable electrical joints; high stability; rapid detection of runaway quench events. We designed experimentally qualified a vacuum pressure impregnated, insulated, partially...
Superconducting flux pumps enable large currents to be injected into a superconducting circuit, without the requirement for thermally conducting current leads which bridge between cryogenic environment and room temperature. In this work, we have built studied mechanically rotating pump employs coated conductor high-Tc (HTS) stator. This has been used excite an HTS double pancake coil at 77 K. Operation of causes within circuit increase over time, before saturating limiting value....
HTS synchronous generators, in which the rotor coils are wound from high-Tc superconducting wire, exciting attention due to their potential deliver very high torque and power densities. However, injection of large DC currents required by presents a technical challenge. In this paper we discuss development brushless exciter operates across cryostat wall inject current into coil circuit. This approach fundamentally alters thermal load upon cryogenic system removing need for thermally...
HTS flux pumps enable superconducting currents to be directly injected into a magnet coil without the requirement for thermally inefficient current leads. Here, we present results from an experimental mechanically rotating pump employing coated-conductor stator and operated at 77 K. We show effect of varying size gap between rotor magnets coated conductor 1 7.5 mm. This leads corresponding change in peak applied perpendicular magnetic field approximately 350 50 mT. observe that our device...
We report on the behavior of a high-Tc superconducting (HTS) homopolar dynamo which outputs DC open-circuit voltage when stator is in state, but behaves as conventional AC alternator normal state. observe that this time-averaged arises from change shape waveform obtained conducting stator. The measured proportional to frequency, and decreases with increasing flux gap between rotor magnet HTS wire. output zero at large gaps, although small differences normal-conducting waveforms are still...
Abstract This paper presents a roadmap to the application of AI techniques and big data (BD) for different modelling, design, monitoring, manufacturing operation purposes superconducting applications. To help superconductivity researchers, engineers, manufacturers understand viability using BD as future solutions challenges in superconductivity, series short articles are presented outline some potential applications solutions. These futuristic routes their materials/technologies considered...
This paper reports on the sensitivity optimization of palladium based hydrogen sensors. The transduction mechanism is volumetric expansion palladium, leading to induced strain in a sensing element. Absorption lattice causes expansion, which can be measured using sensors attached palladium. transduced from expanding dependent not only partial pressure and temperature, but also geometry mechanical transfer sensor. In this we demonstrate design validation sensor for defined concentration...
High-temperature superconducting (HTS) magnet systems conventionally require normal-conducting current leads, which connect between the HTS circuit and an external power supply located at room temperature. These leads form a thermal bridge across cryostat wall, they represent dominant heat load for many applications. The use of flux pump device is alternative approach to exciting coil, can eradicate this parasitic load, as such devices do not direct physical connection circuit. However,...
Despite their proven ability to output DC currents of >100 A, the physical mechanism which underpins operation a high-Tc superconducting (HTS) dynamo is still debated widely. Here, we show that experimentally observed open-circuit voltage, Vdc, due action overcritical eddy within stator wire. We demonstrate close agreement between experimental results and numerical calculations, large over-critical flow during certain parts cycle. These experience non-linear local resistivity alters...
Abstract Fiber-optic thermometry has the potential to provide rapid and reliable quench detection for emerging large-scale, high-field superconducting magnets fabricated with high-temperature-superconductor (HTS) cables. Developing non-voltage-based schemes, such as fiber Bragg grating (FBG) technology, are particularly important applications magnetic fusion devices where a high degree of induced electromagnetic noise impose significant challenges on traditional voltage-based methods. To...
High current operation of HTS magnets is desirable for many applications, but operating currents are typically limited by resistive heating the normal-conducting leads, which connect cryogenic magnet coil to a room-temperature electronic power supply. Rectifying flux pumps feasible alternative solution as they enable be directly injected into via closed superconducting circuit. In this work, we have developed and demonstrated two prototype self-rectifying pump devices capable delivering very...
A 100 kW, 4500 RPM synchronous superconducting motor is being built at the Paihau-Robinson Research Institute, Victoria University of Wellington, New Zealand. The has excitation field coils on rotor and a conventional stator winding. To minimize mass an air-core type, meaning no ferromagnetic materials are employed inside motor. Some salient features this include: 1) winding employing REBCO CORC conductor; 2) powered with contactless dynamo exciter; 3) EM shield for protecting from high...
Currently, there are no simple sensing techniques for determining in real-time both the severity and location of structural damage a composite caused by dynamic impact event. Materials known which emit light when they fractured. This fracture-induced emission is as triboluminescence. A triboluminescent material embedded in, or attached on, structure could act sensor. The occurrence given intensity resulting light. Since fracture-initiated, signal would be generated sensor until occurred....
We have manufactured lengths of up to 10 m Roebel cable from wide strips second generation YBCO wire. The are first screened using magnetic scanning check for superconductor defects avoid incorporating poor quality wire into the cable. Manufacturing issues such as long length registration strand crossovers and maximum yield strip is discussed. Differences in cutting winding due different tape substrate materials shown be minimal. report electrical measurements on samples HTS Insulation which...
Dynamo-type high-temperature superconductor (HTS) flux pumps are fully superconducting dc current sources for HTS magnet coils, which eliminate the need external leads. Previous work has focussed on dynamos employing a single-coated conductor stator wire, and maximum output is found to be limited by effective internal resistance of wire. It expected that adding additional wires in parallel will increase current. However, there have been few experimental reports this effect, nor influence...
Abstract Dynamic resistance can be observed in a superconducting tape carrying DC current which is exposed to an oscillating magnetic field. This effect attributed the interaction between transport and moving fluxons, occur various components including high temperature (HTS) flux pumps, fast-ramping magnets HTS rotating machines. Although conventionally expressed terms of ‘resistance,’ phenomenon inherently transient nature, voltage drop across superconductor follows time-dependent periodic...
Superconducting flux pumps enable dc supercurrents to be injected into a superconducting coil without direct connection an external current supply. Here, we report experimental data from dynamo-type pump employing high-T <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> stator. This device employs mechanical rotor that rotates outside the cryogenic envelope, and excites circuit through cryostat wall via magnetic formed between We show...
The no-insulation (NI) winding method is an effective technique for coils from high-T c superconductors (HTS).NI are electrically and thermally robust due to their ability radially bypass current away the fragile superconducting path when necessary.This avoids stored magnetic energy being entirely discharged on local defects in HTS tape.However, increased degrees of freedom distribution makes finite-element modelling these a complicated multi-level problem.Here we present validate 2D axially...
Abstract High temperature superconducting (HTS) flux pumps can generate ultra-high currents (>1 kA) without the requirement for thermally inefficient room current leads. Ultra-high enable physically smaller magnets with significantly less inductance unlocking new design opportunities. However, limited by intrinsically low electrical power efficiencies, existing HTS cannot output high voltage or power. In this work, we design, devise, and experimentally verify a transformer–rectifier type...
This paper presents experimental and modelling results of an ultra-compact self-rectifier flux pump energizing a superconducting coil. The device fits inside volume 65x65x50~mm generates up to 320~A dc through the coil peak output voltage 60~mV. We also develop present full electromagnetic effective circuit model compare its predictions results. show that our can reproduce accurately charging load it reproduces systematic dependence maximum current on input waveform. experiments together...
The use of smart damage-detection systems may have considerable benefits for equipment operators. As sensing elements a health-monitoring array, piezoelectric offer potential benefits. In particular, 0-3 piezocomposite been identified as good candidates since they the embedment within advanced fibre composites. Ultrasonic Lamb waves shown to technique large-area damage detection It has that S0 mode enable quantitative estimate degree be obtained. A comparison various transducer wave is made...