Power generating by high pulse mechanical stimulation ofmagnetic coupled NdFeB and Terfenol-D

摘要

Rising requirements for a new constructions, devices and machines force engineers to monitor them all day long.An attractive solution seems to be applications of wireless sensors. However, there is a barrier limiting theirapplication, which is the need to supply them with an electrical power over extended period of time withoutusing additional wiring or batteries. The potential solution of this problem seems to be an energy harvesting.Most methods of obtaining the energy from the external sources e.g. vibrations, is to use piezoelectric materials.However, the amount of energy generated by piezoelectric materials is smaller than most electronic devicesneed. Therefore a new method for generating a pulse of energy and conditioning for other loads devices mustbe developed. This paper proposes a new energy harvesting device based on magnetostrictive material. In thecourse of the experiments with using Terfenol-D rods as actuators and sensors it has been observed interestingphenomenon. Mechanical impact (e.g.energy between 1J and 10J in infinite time) to magnetic core based onTerfenol-D rod (diameter 5mm, length 10 mm), NdFeB permanent magnets and coil allowed get electric powersignal enough to supply device of 100 Ohm load on their active state (typical low power controller). In comparisonto the same magnetic circuit built with other typical ferromagnetic materials e.g. Armco iron, showed effect10 times lower or none. Tests and experiments showed the important role of coupling Terfenol-D and NdFeBpermanent magnets, their configuration and variable coil parameters determined this effect. In regard to theresults the authors proposed the construction of a new impulse harvesting method based on Terfenol-D materialfor low impedance load.