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{Fully superconducting (SC)machines hold immense promise for high-power-density and higher efficiency machine solutions for offshore wind turbine applications. In this paper, a 10MW air-core fully SC machine is designed for offshore wind turbine applications. This machine design is considered with inside armature coils and outside rotating field coils. In this topology, shield iron can be eliminated or reduced by replacing it with shield coils which contain the magnetic flux inside the machine. This machine is attractive for off-shore wind turbine application due to its high-power density and high efficiency compared to a conventional shield iron design. However, due to the introduction of additional shield coils, this topology uses relatively more amount of SC material than a conventional shield iron design. Therefore, a tradeoff between the shield coils and the shield iron is explored in this paper. In addition, machine designs with different pole-counts are investigated to identify the optimal pole-count design for a low-speed application. A detailed ac loss calculation is evaluated for the machine and required cryocooler power is evaluated to obtain the machine efficiency.
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This content will become publicly available on January 7, 2026
Low-Power ULF Transmitter Design Using Static Permanent Magnet
This paper presents a low-power Ultra Low Frequency (ULF) transmitter design that uses a static, permanent magnet to bring the surrounding magnetic shield near saturation. A low-power control coil modulates this static magnetic field by toggling sections of the shield between saturated and unsaturated states. The transmitter, operating at 400 Hz and tested using a 3D magnetometer, demonstrated an increase of 22.3 dB along the pole at 800 Hz and a 17.7 dB increase at 400 Hz perpendicular to the pole, with a further 33 dB enhancement than the control coil’s leakage at 800 Hz. These results highlight a novel method for efficient magnetic field modulation with significantly lower power requirements than traditional approaches. This novel approach reduces power consumption and opens new possibilities for designing scalable, energy-efficient ULF communication systems, with potential applications in underwater communication, remote sensing, and long-range wireless networks.
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- Award ID(s):
- 2126443
- PAR ID:
- 10645081
- Publisher / Repository:
- IEEE
- Date Published:
- Page Range / eLocation ID:
- 274 to 275
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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