Effect of Rotor Topology on the Performance of Counter-Rotating Double-Sided Flux Switching Permanent Magnet Generator

Recently, electric power generation from direct-drive counter-rotating wind turbine has gained considerable attention. Consequently, employing an efficient and a high power density electric generator is important. In this regard, flux switching permanent magnet generator with double-sided structure is one of the potential candidates for this purpose due to its features like inherently magnetic gearing effect, high power density, high reliability, and robust rotor structure. In this regard, rotor structure of double-sided flux switching permanent magnet generator is one of the most important factors which can highly affect the machine's performance due to the fact that, rotor geometry is the main part in the flux switching procedure of double-sided flux switching permanent magnet generator. Consequently, this paper presents a comprehensive analysis of counter-rotating double-sided flux switching permanent magnet generator with segmented rotor and laminated rotor in which a bridge is located between adjacent rotor poles. The finite element simulations and experimental tests results showed that the proposed generator with laminated rotor gained from the higher power density in comparison with the segmented one whereas in the case of segmented rotor, the torque ripple is lower.