Design study of dual stator Radial Field Permanent Magnet generator for small wind turbine

The Radial Field Permanent Magnet(RFPM) generator has numerous advantages such as high output voltage and high output power, high efficiency. In addition, the manufacturing is easier than AFPM generator. However, the slotted RFPM generator produces the cogging torque. It would increase torque ripple and generate vibration and noise. In this paper, the design analysis of the electromagnetic structure and the cogging torque reduction of RFPM generator for wind turbine is studied. Firstly, the design of the pole-arc ratio to increase the output generated voltage and to reduce the cogging torque is studied. Secondly, the design of the displacement angle of the inner stator and the outer stator to reduce the cogging torque is studied. The design of RFPM generator was calculated by 2D FEM(Finite Element Method).