VIBRATION-BASED ENERGY HARVESTER FOR SUSTAINABLE STRUCTURAL HEALTH MONITORING SYSTEM: A CASE STUDY ON A PRESTRESSED CONCRETE GIRDER

Tóm tắt

Energy harvesting technology generating electrical energy from structural responses has been in the
spotlight recently because of the development of self-powered autonomous wireless sensor systems. This
study proposed and tested a high-sensitivity, high-durability, low-cost vibration power-generating device
using a magnetostrictive element (Fe-Ga alloy) on a real-scale prestressed concrete girder to investigate its
practical performance. The device comprises a unimorph layer having a magnetostrictive element attached
to a U-shaped frame with a permanent magnet for magnetic bias wound about by a coil. An evaluation of a
prototype device using a Fe-Ga element of 4 × 0.5 × 16 mm was performed. With a weight of 1221 g attached,
an open-circuit voltage of ~1 V at an oscillation of 9.058 Hz and 3.8 m/s2 was generated by free damped
vibrations applied via a person jumping vertically from a chair to the girder. In addition, parametric studies
were carried out by changing impact locations, weights, and device locations in order to examine their
possible effects on the performance of the proposed energy harvester.