Broadband Rotational Energy Harvesting with Non-linear Oscillator and Piezoelectric Transduction

[摘要] Rotational energy is widely distributed in many industrial and domestic applications, such as ventilation systems, moving vehicles and miniature turbines. This paper reports the design and implementation of a bi-stable rotational energy harvester with wide bandwidth and low operating frequency. The rotational energy is converted into electricity by magnetic plucking of a piezoelectric cantilever using a driving magnet mounted on a rotating host. The bistable condition is achieved by introducing a fixed magnet above the tip magnet at the cantilever's free end. The repulsive magnetic force between the magnets creates two equilibrium positions for the piezoelectric beam. The harvester is designed to operate in the high energy orbit (interwell vibration mode) to extract more energy from the rotational energy source. Harvesters with and without bistability are compared experimentally, showing the difference of power extraction on both the output power and bandwidth. The method proposed in this paper provides a simple and efficient way to extract rotational energy from the ambient environment.

[发布机构] Department of Electrical and Electronic Engineering, Imperial College London, Exhibition Road, London; SW7 2AZ, United Kingdom^1

[效力级别] 能源学

[关键词] Ambient environment;Design and implementations;Equilibrium positions;Non-linear oscillators;Operating frequency;Piezoelectric beam;Piezoelectric cantilevers;Ventilation systems