Host: The Japan Society of Mechanical Engineers
Name : Dynamics and Design Conference 2016
Date : August 23, 2016 - August 26, 2016
In this research, we propose a vibration energy harvesting (VEH) system contributing to structural health monitoring in many spacecraft. Among four types of VEH – electromagnetic, electrostatic, piezoelectric, and magnetostrictive - we exploit the magnetostrictive vibration energy harvester in this research because of its strength and workability. The magnetostrictive type is composed of a magnetostrictive material. This material is one of the metal materialsthat showsthe Virari effect. The magnetization of the material varies when external force is given to the material. Following Faraday’s law of induction, a solenoid coil picks up electrical energy when the magnetization varies magnetization. This is the principle of magnetostrictive VEH system. We focus on the control method and the construction of the electric circuit connected with the magnetostrictive element. Although, in the past many researchers used the passive circuit, also called standard circuit, the author thinks the nonlinear switching circuit has more potential because of flexible control and vast scope of application. Indeed nonlinear method suggeststhat magnetostrictive VEH system could drive many kinds of electric devices especially when they have high load impedance. This notion is based on semi-active damping method. The nonlinear method uses switching circuit and passive elements and makes the electric current increase with the switch process. As a mechanical vibration isinduced by an oscillator, part ofthe mechanical energy is transformed into electrical energy and the mechanical energy decreases. This paper presents nonlinear control circuit with a switch and control logic, and an analysis of mechanical and electrical dynamics. As a result of the analysis in the case of a vibration with 1 degree of freedom when a force oscillation is applied, we conclude that both the electrical power supply from the mechanical system and the harvesting energy in load resistance increases.
