A5075694827- Physics of Superconductivity and Magnetism
- Superconducting Materials and Applications
- Frequency Control in Power Systems
- Magnetic confinement fusion research
- Geomagnetism and Paleomagnetism Studies
- Magnetic Field Sensors Techniques
- Superconductivity in MgB2 and Alloys
- Particle accelerators and beam dynamics
- Magnetic and transport properties of perovskites and related materials
Sichuan University
2022-2024
The flux pumps can realize non-contact excitation of high-temperature superconducting (HTS) magnet and eliminate heat leakage caused by current leads. However, earlier proposed pump needs to be installed inside the cryostat, which leads additional load cryogenic system. Here, we report successful demonstration a through-wall linear-motor type pump, with its heating parts such as copper windings completely outside while generated is dissipated in air insulated from cryostat. With an...
A kilo-amp linear-motor type flux pump with the maximum output DC current exceeding 1610 had been designed and manufactured. We optimized large-current based from previous design, shortened travelling wavelength of pump, simulated its magnetic density distribution COMSOL Multiphysics, obtained present design parameters after analysis. placed 12 superconducting single loops side by in air gaps on both sides used to charge them. applied different gap, was measured at 1619 liquid nitrogen 77 K....
In order to further optimize the size of linear-motor type flux pump, an updated motor pump device with single side DC winding was designed and fabricated. Compared previous generation traveling wave length 21 mm, volume this 15 mm is reduced by nearly 30% pumping current capacity increased more than 30%, which generated same biased AC travelling magnetic in airgap, pumped into high temperature superconducting (HTS) closed-loop a non-contacting manner, based on macroscopic coupling effect....
This paper proposed and demonstrated a feedback control method for high temperature superconducting (HTS) dynamo, which was based on an additional DC coil. the theory of macroscopic magnetic coupling effects (MMCE) discovered by Wang Coombs, "Macroscopic effect: The physical origination high-temperature flux pump," <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Phys. Rev. Appl.,</i> using this theory, we had realized very flexible accurate...
This paper investigated the method of using multiple linear-motor flux pumps to increase central magnetic field an HTS magnet composed six stacking insulated YBCO double pancake coils. In this work, we compared two different excitation methods based on pumps, i.e., in series and segmented excitations, investigate their exciting performances magnet. Experiments showed that excitation, maximum operation current was limited by coil smallest critical current. On other hand, both each were...
High temperature superconductivity (HTS) flux pump can be used as the exciter to inject direct current into superconducting excitation coil of a synchronous motor, without lead and with low thermal efficiency, which will reduce cryogenic volume improve efficiency HTS motor. However, has non-negligible impact when it is running continuously for long time within Dewar, cause heavy heat burden system. Therefore, based on linear-motor type previously invented in our laboratory, this paper...
As a travelling-wave flux pump, the HTS dynamo generates DC-biased AC travelling wave on stator tape placed in air-gap, which can output large DC current into an coil without need for leads, thus effectively reducing heat leakage and operational cost comparing with conventional contact power supplies. In this paper, we introduce method to enable symmetric bipolar of dynamo, based "four-quadrant" control originates from theory macroscopic magnetic coupling. This uses N-S arrangement permanent...
Due to the properties of high-temperature superconducting (HTS) materials, current attenuation is inevitable during closed-loop operation HTS magnets. When a contact dc power supply used supplement this attenuation, it inevitably creates huge thermal burden on cryogenic system. The flux pump revolutionary new source that can charge magnet wirelessly. However, for magnets with large inductance, cannot fast adjust due its small output voltage. Here, we present method regulate in using and...
Due to the properties of high temperature superconducting (HTS) materials, current attenuation is inevitable during closed-loop operation HTS magnets. When a contact DC power supply used supplement this attenuation, it inevitably creates huge thermal burden on cryogenic system. The flux pump revolutionary new source that can charge magnet wirelessly. However, for magnets with large inductance, such as particle accelerator and magnetic confinement in Tokamak devices, cannot fast adjust...