Experimental Study of Power Harvesting from Vibration using Giant Magnetostrictive Materials

Abstract

The interest in research and development of smart actuators, sensors and power generators that used Giant Magnetostrictive Materials (GMM) is growing. Both academia and industry are actively looking for bread utilization of GMM technology for different applications (active vibration and noise control, structural health monitoring, self-powered electronic equipments and systems, MEMS, robotics, etc.). In the paper we present results of experimental study of vibration-to-electric energy conversion using giant magnetostrictive materials. The magnetostrictive power harvesting device was built using Terfenol-D rod. The fundamental base for development of the device is a Villari effect. That is, by applying a mechanical stress to a magnetostrictive material, the magnetization along the direction of the applied stress of the material varies due to the magnetostrictive effect. The flux variation obtained in the material induces an emf in a coil surrounding the material. Test rigs measurement data have confirmed the expected function of the developed magnetostrictive power harvesting device. Electrical power of the device for different input parameters of external vibration field was examined. The experimental results are presented for Terfenol-D rod with 50 mm in length and 15 mm in diameter which have shown that efficiency of the developed magnetostrictive power harvesting device varies from 8% to 25%.