Performances Comparison of Two Surface-Mounted Permanent Magnet Generators with Fractional - Slot Windings

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The paper deals with the design, FEM analysis, and testing of two surface-mounting permanent magnet (PM) generators with fractional - slot windings for wind applications. The aim of this work has been to build two PM generators with simple structure, good performances and very low cogging torque. Therefore, two kind of stator with different slot/pole combinations was chosen. Both stators have a very high Least Common Multiplier (LCM) between the number of poles and slots. The paper presents the main design aspects, the performance characteristics and some test results of the two PM generator prototypes of a 5 kW-120 rpm. Good agreement between simulated and experimental results has been achieved and some practical conclusions are presented
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Permanent Magnet Generator; Low Speed; Fractional - Slot Windings; FEM Analysis

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