In response to the challenges posed by uncontrolled amplitude during galloping and narrow effective bandwidth during vortex-induced vibrations in current energy harvesters, a novel wind-adaptable piezoelectric energy harvester utilizing a rigid-flexible compound blunt body (W-APEH) is proposed. The rigid-flexible compound blunt body improves environmental adaptability and power generation capacity. During the transformation process of the rigid-flexible compound blunt body from a Y-shape to an r-shape, a vibration pattern changes from galloping to coupled vibration, then to vortex-induced vibration. The feasibility of the structure and principle of the W-APEH were proved through a series of simulations and experiments. The higher proportion of rigid wings within a blunt body increases the susceptibility to galloping. A larger windward angle will delay the occurrence of galloping in the W-APEH, shorten the time of coupled vibration, and reduce the output voltage. In the case of the flexible wing thickness remains below 0.3 mm, an increase in thickness leads to an extended galloping time, with vortex-induced vibrations occurring later. Specifically, the onset wind speed is only 3.5 m/s, and the working wind speed range is 5–21 m/s with appropriate structural dimensions. Furthermore, the W-APEH provides a maximum output power of 3.78 mW at an optimal load resistance of 250 kΩ.
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