Direct drive field winding synchronous generators for medium power wind turbines

This paper presents design and analysis of direct drive field winding wind generators. The power of salient pole synchronous wind generators is 660 (kW) with 28.5 (rpm). Rotor is skewed to reduce the torque oscillations. Magnetic analysis of wind generators is done using finite element method. Temperatures of wind generator structure are analyzed using numerical thermal calculations. Finally a direct drive permanent magnet wind generator is also designed and analyzed to compare with field winding wind generators performances and dimensions.