Experimental investigation on piezoelectric energy harvesting from vehicle-bridge coupling vibration

Abstract

Piezoelectric energy harvesting from vehicle-bridge coupling vibration is tested in this work. Firstly, a vehicle-bridge coupling platform is introduced, and the dynamic response of the bridge is measured and analyzed. Based on the vibration characteristics of the coupling platform, two piezoelectric energy harvesters (PEHs) with different fundamental frequencies are designed and manufactured, denoted as PEH-1 (designed with the natural frequency of the bridge) and PEH-2 (designed with the frequency of vehicle-bridge coupling vibration). The electromechanical characteristics of the PEHs are tested experimentally. Then, the voltage outputs of the PEHs are measured under nine different cases and the energy harvesting performance of the PEHs are discussed. Finally, the influences of the resistance load on energy harvesting are analyzed theoretically. Experimental results show that the voltage output of PEH-1 has its peaks when the vehicle enters into or leaves the bridge, and is almost zero when the vehicle moves on the bridge. The voltage output of PEH-2, by contrast, is still obvious when the vehicle moves on the bridge. The experimental results also show that more energy can be harvested when the PEHs are installed at the middle of bridge. An interesting result is found. The harvested energy is different even if the PEHs are installed at two symmetric positions of the bridge.