Skewing angle magnet and coil reduced starting torque in a permanent magnet synchronous generator for a small vertical axis wind turbine

Abstract. This work investigated the effects of changing the skewing angle of a magnet coil on starting torque in a permanent magnet generator (PMSG) fitted in a low speed vertical wind turbine. The optimal skew angle of the magnet-coil was found to be 15–0 (degrees), generating 1.22 (N-m) starting torque and 295.40 (W) compared with a skew angle of 0–0 (degrees). This skew angle reduced starting torque and power by 5.43 % and 1.96 %, respectively. A Savonius and H-Darrieus stacked turbine blade operated at a wind speed of 1.90 m/s and 1.31 N-m torque. This blade was used in a fully operational vertical wind turbine, was connected to the PMSG that can cut-in speed of 2.1 m/s. It was concluded that a 15–0 (degree) skewing angle magnet-coil can be applied to a low speed vertical wind turbine.