Study of Flux Switching Machine Rotors from EMF Harmonic Components Point of View for Direct Drive Wind Power Application and Design of a New Topology with Double Rotor & Toroidal Coil

By development of wind farms, especially in direct drive applications, it requires more simplicity and less depreciation. In this application, by removing the gearbox, in addition to simplifying the entire system, the losses and related maintenance costs are eliminated. The main problem for these generators is their large dimensions that makes it difficult to construct, transfer, assemble and install it on the power plant tower, so flux switching machines can be a good option for this application because the stator can be built and assembled modularly. In general, in the concept of direct drive wind power application, three topics including high number of poles for operation at low speed and high torque, capability a stator with modular structure for possibility multi-phase generator and power electronics parts, and desirable electromagnetics feature are considered by designers. In this paper, a generator with simple configuration & different rotor poles is studied in 2D finite element software so that, it has a desired electromagnetic specification for direct drive wind power application. Finally, by presenting and examining a simple and suitable geometry of the 14-tooth rotor, a new configuration is proposed according to the desirable electromagnetic behavior and producing an almost sinusoidal voltage waveform for each coil, that could be a good choice for direct drive and multi-phase applications.