Magnus Wind Turbine Emulator With MPPT by Cylinder Rotation Control

Abstract

An emulator for the nonconventional Magnus wind turbine was designed and developed in this study. A brief discussion is made of this special case of horizontal axis wind generator and of the main physics principles involving the Magnus phenomenon. A mathematical model was used to emulate the static behavior of the Magnus wind turbine and a detailed analysis is presented about its peculiar rotating cylinder characteristics. Based on the relationship between cylinder blade rotation and power coefficient, a hill climb search algorithm was developed to perform maximum power point tracking. The impact of the cylinder's rotation speed on the turbine net output power was evaluated. A controlled direct current motor was used to provide torque, based on the Magnus turbine model, and drive a permanent magnet synchronous generator (PMSG); the latter was controlled by a buck converter in order to extract the maximum generated power (MGP). Simulations of the Magnus wind turbine model and its maximum power point tracking (MPPT) control are also presented. A prototype of the proposed emulator was developed and operated by a user-friendly LabVIEW interface. Measurements of the power delivered to the load were acquired for different wind speeds; these results were analyzed and compared with simulated values showing a good behavior of the emulator with respect to the turbine model. The proposed control technique for maximizing the output power was validated by emulated results. The modeling and development of the Magnus turbine emulator also serve to encourage further studies on generation and control with this wind machine.