Snap-through triboelectric nanogenerator with magnetic coupling buckled bistable mechanism for harvesting rotational energy

We propose a snap-through triboelectric nanogenerator with magnetic coupling and buckled bistable mechanism to harvest rotational energy (ST-RTENG). The buckled bistable beam generates convex and concave snap-through under magnetic excitation, which can significantly increase the contact force of the functional materials of triboelectric nanogenerator (TENG), thereby significantly improving the electrical output. By adopting a magnetic coupling non-contact energy transfer mechanism, the drive part and the electromechanical conversion part are easily physically separated, which improves the robustness of the system in the harsh environment. The electromechanical coupling dynamic model of the system is established and verified by experiments. The different modes and key parameters of the magnet arrangement are investigated. The ST-RTENG with two pairs of magnets with staggered poles has a maximum voltage of 1235 V at a rotating speed of 150 r/min and a maximum average power of 778 μW at a rotating speed of 800 r/min. The prototype can light up more than 1000 LEDs under low speed excitation, and realize self-powered temperature monitoring and wireless transmission. The rotational energy harvester with magnetic coupling buckled bistable mechanism proposed in this paper can be used for wind energy harvesting in the field environment, self-powered state monitoring of the pressure pipelines, and other applications that require isolation of external excitation and electromechanical conversion components.