Design and parametric analysis of a ferromagnetic material-excited wideband piezoelectric rotational energy harvester for self-powered electronics

This study proposes a ferromagnetic material-excited wideband piezoelectric rotational energy harvester to overcome the limitations of conventional magnetically excited piezoelectric rotational energy harvesters. Unlike traditional systems that require heavy magnets directly mounted on the piezoelectric transducer, the proposed device employs a lightweight nickel-based PZT transducer. This design minimizes stress concentration, increases the resonant frequency, and broadens the operational bandwidth. Through theoretical modeling, finite element simulations, and experimental validations, we analyzed the effects of excitation distance, number of magnets, and pole arrangements on the device's performance. Key findings revealed that the output voltage reached 35.81 V at a 1 mm excitation distance and 1118 r/min, under a double-pole excitation condition. Similarly, the peak power output achieved was 9.8 mW at an optimal load resistance of 20 kΩ. Experimental results further demonstrated that the device could power 250 light-emitting diodes and various low-power electronic devices, validating its practical feasibility. These results highlight the proposed energy harvester as a reliable and efficient solution for Internet of Things systems, wearable electronics, and other compact applications, paving the way for advancements in self-powered technologies.