This study proposes a linear magnetic gear (LMG). Unlike conventional LMGs, the proposed one purposely uses high-temperature superconducting (HTS) bulks replace permanent magnets (PMs). The high-speed mover of the magnetic gear is connected to the secondary of the linear permanent magnet generator (LPMG), which constitutes a direct-drive wave power system that converts wave energy into electrical energy. First, the LMG structure is presented according to the principle of magnetic field modulation, and the authors briefly analyzed the number of pole pairs of inner, outer, and ferromagnetic modulators. Second, they also established a finite element analysis model to analyze the performance of magnetic gear, including magnetic field distribution, radial air gap magnetic flux density, and force characteristic. An LMG with HTS bulks not only increased the radial air gap magnetic flux density but also improved the speed of LPMG. In conclusion, this experiment verifies the efficacy of direct-drive wave power take-off system and effectively converts wave energy into electrical energy.

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Linear magnetic gear with HTS bulks for wave energy conversion

References

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