An modular-type axial-flux permanent magnet synchronous generator for gearless wind power systems

In this paper, the design and characteristics analysis of dual axial-flux permanent magnet synchronous generator, 60 |Hz|, 10 |kVA|, 300 |rpm| for wind energy system application are presented. The dual axial-flux generator has inherently desirable features such as; (1) by employing two air gaps, the rotor-stator attractive forces are balanced and no net axial or thrust load is applied on the generator bearings; (2) heat produced by the stator windings appears on the outside of the generator, and it is easy to remove the heat. This paper describes characteristics of a dual axial-flux type permanent-magnet generator for a gearless wind energy system, which aims to satisfy the variable operating conditions. Finite-element method (FEM) is applied to analyze generator performance at variable loads. The results of FE analysis show this generator has a promising future for wind turbine applications.