Design and Modelling of a Non-linear Spring-mass Energy Harvesting Device for Wind Turbine Applications

This project addresses the development of a vibrational energy harvester for deployment at the blade-tips of large-scale wind turbines. In this work, a non-linear single-degree-of-freedom massspring system is chosen on the basis of an extensive literature review. An electromagnetic energy harvester...

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Detalles Bibliográficos
Autor: Bonet Bach, Jaume
Tipo de recurso: tesis de maestría
Fecha de publicación:2022
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/367342
Acceso en línea:https://hdl.handle.net/2117/367342
Access Level:acceso abierto
Palabra clave:Wind turbines
Springs (Mechanism)
Electrodynamics
Vibration Modelling
Energy Harvesting
Vibrations
Spring-Mass
Electro-Dynamic
Wind Turbines.
Aerogeneradors
Ressorts (Mecànica)
Electrodinàmica
Àrees temàtiques de la UPC::Energies::Energia eòlica::Aerogeneradors
Descripción
Sumario:This project addresses the development of a vibrational energy harvester for deployment at the blade-tips of large-scale wind turbines. In this work, a non-linear single-degree-of-freedom massspring system is chosen on the basis of an extensive literature review. An electromagnetic energy harvester based on a magnet moving between two springs (an approximate volume of 10x3.5x3.5 cm3 and natural frequency < 10 Hz) is tested experimentally for different distances between the two springs. Additionally, a model that aims to predict the harvester power output is developed. The model consists of a coupled electro-dynamic system to represent the dynamic and the electrical behaviour of the harvester, with the discretization of the coil to approximate the magnetic damping and the electromotive force generated. A finite element analysis carried with COMSOL Multiphysics, based on the remanent magnetic field density, is used to determine the magnetic field of the magnet in the centre of the coils. The results show that when the distance between the top and the bottom spring is increased from 16 mm to 18 mm, there is a shift of frequency that goes from 9 Hz to 8 Hz and an rms power generated of 1.53 mW and 1.27 mW, respectively, for a 0.2 g rms acceleration. For a 0.5 g rms acceleration the shift of frequency goes from 9.5 Hz to 8.5 Hz and the rms power generated was 2.28 mW and 1.59 mW respectively. The model is able to predict the power output and the frequency shift for distances between springs close to the one used to tune the model (+2 mm). Further development on the model will allow to use the MATLAB scripts to optimise the harvester and obtain its main characteristics for a given wind turbine blade and operational characteristics.