Design and FEM analysis of five-phase permanent magnet generators for gearless small-scale wind turbines

Currently the renewable energy presents an increasing interest and special attention is given to the small scale wind turbines, used to generate electricity for domestic needs. Their purpose is to produce electric energy at increasingly smaller speeds of the wind and with improved economically efficiency. This paper presents the design and study of the behavior for a direct drive permanent magnet synchronous generator, intended to be used for small wind turbines. The permanent magnet generator is designed to provide the power of 1kW corresponding to 100 revolutions per minute [rpm]. In order to obtain a voltage ripple as small as possible, the proposed solution takes into consideration a five-phase winding and a rectifier bridge. The performance of the proposed model are presented in a comparative analysis; the simulations are of transient type in 2 dimensions, using a software package based on FEM.