Abszracr-This paper evaluates the mechanical design and construction of a 300 kW, double-stage, axial-flux permanent magnet (AFPM) machine. Finite element simulations were used to determine the severity of the attraction force between the rotor discs. The huge attraction force also caused problems during machine assembly, because the closer the discs are brought in, the larger the force. The results obtained from the simulations suggested an increase in yoke thickness in order to withstand the attraction force on it. The simple lumped parameter thermal model was established to evaluate the effectiveness of the air-cooling, which is compared with measurements taken on a prototype AFPM machine.

This paper describes a hybrid method for calculating the performance of a coreless stator axial flux permanent-magnet (AFPM) generator. The method uses a combination of finite-element analysis and theoretical analysis. The method is then incorporated into a multidimensional optimization procedure to optimally design a large power coreless stator AFPM generator. The measured performance of the manufactured prototype compares favorably with the predicted results. The design approach can be applied successfully to optimize the design of the coreless stator AFPM machine.Index Terms-Axial flux, design, finite-element methods, optimization methods, permanent-magnet generator.

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The fatigue failure of the stent component of a percutaneous aortic heart valve (PAHV) is an event that could be fatal to the patient. Therefore, the fatigue life prediction of a stent intended for application in a PAHV is a major consideration during the design and development phase of the device. Since the stent component will be subjected to both cyclic blood pressure as well as cyclic valve-leaflet forces, the combined effect of these loads must be taken into account for the analysis of the fatigue life. This paper expands on a methodology developed by Marrey et al.10 to incorporate the combined loading of both the cyclic blood pressure as well as the cyclic leaflet forces in the fatigue life assessment of stents intended for application in percutaneous aortic heart valves. It was found that the developed methodology, which utilizes the finite element method (FEM), provides a simple and cost-effective tool to quantitatively determine the fatigue resistance of the stent component, thereby enabling the designer to compare different stent designs with respect to their resistance against fatigue. Two different stent designs were analyzed using this approach and it was found that they exhibited similar resistances to fatigue and that resistance to fatigue is influenced by strut width.