Design optimization study of a torus type axial flux machine

Abstract

Axial flux machines are used frequently in wind energy applications due to their high power densities and efficiencies. However, the parametrical dependencies of those generators affect the generated power and efficiencies. For instance, turbine blade structures dimensions, change dramatically the speed and torque characteristics. Hence, this study includes a pursuit of optimization and the related design parameters for an axial generator in terms of its off grid operations. The analytical design relations and simulated data have shown that the geometric dimensions and morphology of the machine can be analyzed effectively under the finite element method and the optimization of the machine can be provided with a good accuracy by applying the response surface optimization. Cogging torque and power density formulated aim function gives a good optimization for the design. According to this approach, the general performance of the machine is maximized and the cogging torque and weight are kept to be decreased. Design variables are optimized by considering the generator size. Consequently, an optimal 4.8% increase in weight can yield to a 27.4% power enhancement in the machine.

Keywords

• Torus design,Response surface,Axial machine,Wind energy

References

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