Watt-level road-compatible piezoelectric energy harvester for LED-induced lamp system

摘要

Road-compatible piezoelectric energy harvesters (RPEHs) have recently been widely demonstrated to power traffic ancillary facilities and intelligent sensing devices. The output power of RPEHs was previously always at the mu W or mW level. A watt-level RPEH (pi x 17.52 x 8 cm(3)), consisting of 40 metal-piezoelectric ceramic units, based on an improved drum-transducer structure is proposed herein. Its electrical productivity under different excitation frequencies and displacements was tested in a laboratory. At a 10 Hz excitation frequency and 2 mm excitation displacement, a maximum output voltage of 25.64 V, maximum output current of 25.64 mA, and maximum output power of 657.41 mW (power density: 6.83 W/m(2)) were observed at a 0.9 k Omega load resistance. Then, its electrical productivity at different vehicle speeds was tested on an actual roadway. When a small-sized vehicle passed the RPEH at a speed of 80 km/h, a maximum output voltage of 40.39 V, maximum output current of 403.9 mA, and maximum output power of 16.31 W (power density: 169.52 W/m(2)) were observed at a 0.1 k Omega load resistance. This is the maximum output power observed thus far on an actual roadway. The RPEH successfully illuminated a 5-m-long LED-induced 300-lamp strip, demonstrating potential for car networking and intelligent transportation. (C) 2021 Elsevier Ltd. All rights reserved.