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永磁辅助同步磁阻电机在宽转速范围内的高效率优点,使其成为高性能调速驱动应用的重要方案.虽然永磁体仅用于辅助目的,但其特性仍然对电机产生重要影响.例如,稀土永磁体辅助的同步磁阻电机面临着成本高、供应链波动大的问题,而铁氧体辅助的同步磁阻电机面临永磁体磁性能较差、易退磁等问题.本文在综合考虑稀土和铁氧体特性差异的基础上,提出了一种新型混合永磁辅助同步磁阻电机.通过在靠近转子外围的磁障中放置少量稀土永磁体,可显著提高电机的抗退磁能力.分析结果表明,稀土与铁氧体的体积比例在略高于5％时,即可在抗退磁能力、单位转矩的成本等因素之间取得很好的平衡.本文设计了一台稀土体积占比为5.5％的混用永磁辅助同步磁阻电机样机,并与两台已有的常规电机(分别是铁氧体辅助和稀土辅助)进行了对比研究.有限元分析和实验结果表明:在三台电机电磁性能基本相同的前提下,混用永磁辅助电机的抗退磁能力显著高于铁氧体辅助电机,而成本明显低于稀土辅助电机.“,”The inherent feature of high efficiency over wide speed range positions permanent-magnet-assisted synchronous reluctance machine (SynRM) as an appealing contender for high-performance variable speed applications. Though the magnets are for assistance only, their characteristics have a significant effect on the machines, e.g., the rare-earth magnet encounters high cost and volatile supply chain issues while the ferrite one faces low energy product and demagnetization problems. This paper proposes a new hybrid PM-assisted SynRM by taking into consideration the effect from the large magnetic characteristic difference between the rare-earth and ferrite magnet materials. The anti-demagnetization capability of the machine can be significantly improved by allocating rare-earth magnets in the barriers adjacent to rotor outer periphery. Comprehensive analysis results have indicated an optimal ratio of slightly above 5％ between rare earth and ferrite magnet volumes strikes a balance between the anti-demagnetization capability and the cost per Newton-Meter for such hybrid machine. A hybrid prototype with 5.5％ rare-earth magnet volume ratio is designed to compare with its existing conventional counterparts which employ ferrite and rare-earth magnets individually. Both the finite element analysis and experimental results have revealed that all three machines have almost identical performance, but the hybrid machine has evidently enhanced the demagnetization withstanding capability over the ferrite PM-assisted SynRM and significantly reduced the magnet cost over the rare-earth one.