Tham khảo tài liệu 'sustainable energy harvesting technologies past present and future part 10', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 7 Vibration Energy Harvesting Linear and Nonlinear Oscillator Approaches Luca Gammaitoni Helios Vocca Igor Neri Flavio Travasso and Francesco Orfei NiPS Laboratory - Dipartimento di Fisica Università di Perugia INFN Perugia and Wisepower srl Italy 1. Introduction An important question that must be addressed by any energy harvesting technology is related to the type of energy available Paradiso et al. 2005 Roundy et al. 2003 . Among the renewable energy sources kinetic energy is undoubtedly the most widely studied for applications to the micro-energy generation1. Kinetic energy harvesting requires a transduction mechanism to generate electrical energy from motion. This can happen via a mechanical coupling between the moving body and a physical device that is capable of generating electricity in the form of an electric current or of a voltage difference. In other words a kinetic energy harvester consists of a mechanical moving device that converts displacement into electric charge separation. The design of the mechanical device is accomplished with the aim of maximising the coupling between the kinetic energy source and the transduction mechanism. In general the transduction mechanism can generate electricity by exploiting the motion induced by the vibration source into the mechanical system coupled to it. This motion induces displacement of mechanical components and it is customary to exploit relative displacements velocities or strains in these components. Relative displacements are usually exploited when electrostatic transduction is considered. In this case two or more electrically charged components move performing work against the electrical forces. This work can be harvested in the form of a varying potential at the terminals of a capacitor. Velocities are better exploited when electromagnetic induction is the transduction mechanism under consideration. In this case the variation of the magnetic flux through a coil due to the motion of a permanent magnet .
