Low-frequency electromagnetic harvester for wind turbine vibrations

In this paper we describe and fully characterize a novel vibration harvester intended to harness energy from the vibration of a wind turbine (WT), to potentially supply power to sensing nodes oriented to structural health monitoring (SHM). The harvester is based on electromagnetic conversion (EM) and can work with vibrations of ultra-low frequencies in any direction of a plane. The harvester bases on a first prototype already disclosed by the authors, but in this paper, we develop an accurate model parameterized by a combination of physical parameters and others related to the geometry of the device. The model allows predicting not only the power generation capabilities, but also the kinematic behaviour of the harvester. Model parameters are estimated by an identification procedure and validated experimentally. Last, the harvester is tested in real conditions on a wind turbine. • A novel Energy Harvester (EH) is described operating in ultra-low frequency range. • The EH is accurately modelled in terms of energy generation and kinematic behaviour. • The estimated model is used to predict its behaviour under arbitrary excitations. • The EH is experimentally characterized in the lab and tested in a real wind turbine.