volume | PIER Journals

Abstract

This paper theoretically describes a new concept of passive contactless concentric magnetic gear, which, unlike the existing ones, does not use any separate modulator structure, and instead, a set of strength modulated permanent magnet pole pieces are introduced on the outer permanent magnet rotor structure. Mathematical analysis shows that stable operation in this proposed system is possible with any specific gear ratio, dependent on the number of pole pieces and on the choice of modulation constant of the pole strength variation. The system described is simpler because of the absence of separate modulator structure. The concept is new, leads to less parts count, and hence deserves consideration due to its simplicity. A simple simulation study result is also included at the end, which confirms the presented theory. The main contribution of the paper is the introduction of a new concept for designing magnetic gears using fewer physical components and showing that it is a viable design and able to produce a tangible toque at a particular gear ratio. In addition, the mathematical theory in the paper leads to interesting new results indicated in the design section of the paper, which have not been seen in the literature known to the author.

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Dr. Md Abul Masrur