Performance of magneto-piezo-elastic cantilever circular array for low-speed efficient wind power generator application

A magneto-piezo-elastic (MPE) cantilever generator using a PZT-based piezoelectric thick film with large dimensions of 120 and 60 mm was fabricated for wind power generator application, and a circular array of the MPE cantilevers was optimally designed by evaluating their output power performance. The geometric parameters of the gap ( d ) between coupled permanent magnets, and the distance ( l ) from the rotation axis, were found to influence the output voltage and start-up wind speed of the MPE cantilevers. The output power was strongly enhanced by accumulating the MPE cantilever circular arrays, depending on the decreased optimal resistive load and the increased optimal rotation per minute (rpm) of the Savonius wind blade. The highest output power of 333 mW at 500 Ω and 18 rpm was achieved by a triple circular array with 18 MPE cantilever generators. It was also demonstrated that the MPE cantilever circular array is sufficiently feasible in an actual windy environment, with superior output power in the low rpm ranges compared with commercial 300 W-rated wind turbines.