Cogging torque sensitivity in design optimisation of low cost non-overlap winding PM wind generator

Low cost and low cogging torque are the most important aspects in the design of direct drive PM wind generators. In this paper a low cost PM wind generator with an irregular, parallel slotted stator is analysed with respect to cogging torque. The sensitivity of average torque and cogging torque to machine dimension variations are investigated. From this a method is proposed whereby regions of low cogging torque can be identified more quickly in the design optimisation. Finite element analysis is used to determine the cogging torque. Calculated results are validated by practical measurements on a 15 kW PM wind generator.

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