Design and Analysis of 42-V Coreless Axial-Flux Permanent-Magnet Generators for Automotive Applications

This paper presents the design and analysis of a novel structure of an axial-flux permanent-magnet machine with iron less stator to generate sinusoidal electromotive force with very low harmonics. The structure is of a special design that is suitable for flux weakening in variable speeds. Flux weakening is done by a mechanical actuator to change the position of windings relative to each other. To confirm the machine performance and the design, analytical and three-dimensional finite-element numerical methods are implemented. The simulations results of the proposed generator coincide very well with the experimental results on a prototype 42-V system realized in the laboratory.