Design-analysis and optimization of 10 MW permanent magnet surface mounted off-shore wind generator

International Journal of Electrical and Electronics Engineering
© 2020 by SSRG - IJEEE Journal
Volume 7 Issue 2
Year of Publication : 2020
Authors : Ramakrishna Rao Mamidi, JagdishMamidi
How to Cite?

Ramakrishna Rao Mamidi, JagdishMamidi, "Design-analysis and optimization of 10 MW permanent magnet surface mounted off-shore wind generator," SSRG International Journal of Electrical and Electronics Engineering, vol. 7,  no. 2, pp. 38-46, 2020. Crossref,


With advancing technology, market environment for wind power generation systems has become highly competitive. Industry has been moving towards higher wind generator power ratings, in particular off-shore generator ratings. Current off-shore wind turbine generators are in the power range of 10 to 12 MW. Unlike traditional induction motors, slow speed Permanent Magnet Surface Mounted (PMSM) high-power generators are relatively challenging and designed differently.
In this paper, PMSM generator design features have been discussed and analysed. The focus attention is on armature windings, harmonics and permanent magnet. For the power ratings under consideration, the generator air-gap diameters are in the range of 8 to 10 meters and active material weigh ~60 tons and above. Therefore, material weight becomes one of the critical parameters. Particle Swarm Optimization (PSO) technique is used for weight reduction and performance improvement. Four independent variables have been considered which are air gap diameter, stack length, magnet thickness and winding current density. To account for core and teeth saturation, preventing demagnetization effects due to short circuit armature currents and maintaining minimum efficiency, suitable penalty functions have been applied. To check for performance satisfaction, a detailed analysis and 2D flux plotting is done for the optimized design.


Offshore wind generator, PMSM, PSO optimization.


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