Analytical and experimental study of electric energy harvesting resulting from nonlinear vibrations caused by the excitation of the harmonic base of a cantilever beam

Analytical and experimental study of electric energy harvesting resulting from nonlinear vibrations caused by the excitation of the harmonic base of a cantilever beam


Analytical and experimental study of electric energy harvesting resulting from nonlinear vibrations caused by the excitation of the harmonic base of a cantilever beam

نوع: Type: thesis

مقطع: Segment: PHD

عنوان: Title: Analytical and experimental study of electric energy harvesting resulting from nonlinear vibrations caused by the excitation of the harmonic base of a cantilever beam

ارائه دهنده: Provider: Ali Oveysi Sarabi

اساتید راهنما: Supervisors: Dr. Alireza Shooshtari

اساتید مشاور: Advisory Professors:

اساتید ممتحن یا داور: Examining professors or referees: Dr. Mehdi Karimi

زمان و تاریخ ارائه: Time and date of presentation: 2024

مکان ارائه: Place of presentation: seminar 2, Mechanic

چکیده: Abstract: Today, the provision of energy resources without using natural resources is an important challenge. The reduction of fossil fuels has led to the emergence of new sciences and technologies in harvesting green energies. Among these sciences, harvesting and storing energy from the vibrations of the surrounding environment has attracted more attention. In this thesis, a vibration mechanism consisting of a cantilever beam and springs with variable locations has been proposed and analyzed. In the proposed mechanism, the amplitude of the beam vibrations and its damping can be controlled with the help of magnetic springs connected to the beam body, which can be placed at different distances from the beam base. Also, an electromagnetic harvester consisting of a magnet and a coil is embedded in this mechanism. The coils are placed in the reciprocating path of the free end of the beam. According to the magnet installed on the free end of the beam, its movement inside the coils causes induced voltage, and finally, the electrical energy is harvested. In order to extract permanent energy from the system, an adaptive controller is proposed. With the help of the proposed controller, the location of the springs is constantly changed. Thus the beam is constantly oscillating for each base excitation. In other words, changing the location of the springs prevents the damping of beam oscillations or the excessive increase of the amplitude of oscillations. The use of the proposed controller makes it possible to extract constant energy from the proposed mechanism despite the presence of unknown external disturbances such as wind waves and sudden changes of sea waves, as well as the uncertainty of the parameters of the beam. The equations describing the electromechanical behavior of the proposed mechanism are derived from Lagrange's equations. Then the obtained equations are numerically solved and the effects of the system parameters on the harvested energy are investigated. On the other hand, the dynamic surface control method is used to design the controller and adaptive laws. The stability of the closed loop system is investigated using the Lyapunov stability theorem. In order to show the effectiveness of the proposed mechanism and controller, a numerical simulation is presented for the beam and after analytical modeling, a prototype of the proposed mechanism is constructed. Finally, it is shown that the experimental and analytical results are in good agreement. Therefore, this mechanism can be used as an effective harvester, especially when the distance of the magnetic springs from the base of the beam is adjusted

فایل: ّFile: