Parametric Investigation of Bistable Vibro-impact Triboelectric Energy Harvester Using Frequency Up-Conversion

Recently, triboelectricity has become one of the most efficient mechanisms for energy harvesting. However, the electrical signal generated by this mechanism is a function of several parameters, such as the surface roughness, the applied mechanical load, the gap spacing, and the thickness of the insulator. This paper parametrically investigates a 2-DOF Vibro-impact triboelectric energy harvesting at low frequencies. Two magnetically coupled cantilever beams integrated with triboelectric generators are modeled as 2-DOFs with lumped parameter modeling. The triboelectric generators produce electrical signals when subjected to base excitation via contact-separation impact motion. Changing the magnets' spacing will change the system's dynamic behavior, and a 5mm was found to be the best for harvesting energy at a low-frequency range. Furthermore, at 5 mm magnet spacing, the effect of changing some parameters, such as the external resistance, the impact damping coefficient, the surface charge density, and the gap spacing, on the harvester's performance was investigated. High performance in terms of the electrical signal generated and operating bandwidth can be achieved by selecting the optimal parameters for the harvester.