A major problem in the design and manufacturing of surface mountedpermanent magnet machines is reliably holding the permanent magnets inplace at high speeds. This paper evaluates a unique rotor laminationdesign for a high pole number, permanent magnet alternator. This buriedmagnet design, which is capable of reliably holding the permanentmagnets in place at high speeds, offers both easier and cheaper assemblywhen compared with the methods currently used in surface mountedpermanent magnet machines. Finite element analysis is used to comparethe buried magnet design with equivalent surface mounted designs andshows that the performance of the alternator is not significantlyaffected by the iron over the magnets. Experimental results from aprototype alternator further corroborate the FEA and show that thedesign is capable of operating at high speeds with no other means ofmagnet retention. In addition, an improvement in the buried magnetdesign which can reduce the lamination complexity is suggested andexamined
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