Experimental analysis of nonlinear piezo-electromagnetic composite human energy harvester

Abstract

To better harvest the kinetic energy of the human and broaden the energy harvest frequency band, a nonlinear piezo-electromagnetic composite human energy harvester (NPE-HEH) is proposed. A magnetic repulsion force between the two groups of magnets makes the energy harvester nonlinear. The excitation experiment and the actual experiment of the human are carried out for the harvester. The excitation experiment results show that there is an optimal resistance value of the harvester to maximize the output power value. When the excitation acceleration is 0.4 g and the excitation frequency is 9 Hz, the output voltage value and the output power of the electromagnetic part of the energy harvester are 0.86 V and 2.47 mW respectively, and the output performance is excellent. When the energy harvester is installed in a backpack with a moving speed of 9 km/h, it can generate 0.7 mW of power. When the energy harvester is placed on the leg, the output performance is good and the output power can reach 1.3 mW. The energy harvester can efficiently harvest energy at low frequencies. This harvester is efficient at low frequencies, compact in size, and easy to carry, making it highly suitable for human vibration energy harvesting applications.