Base excited hybrid energy harvesting

This paper proposes a novel energy harvesting system model based on combined electromechanical and electromagnetic transduction technique. A cantilever substrate (beam) with piezoelectric (PZT) patch and a mass at the tip is considered for electromechanical transductions. A magnet is hanged through a spring at the tip of the composite beam over a printed circuit board. When the cantilever system is subjected to base excitations, the motion of the magnet relative to a conducting circuit placed near it generates electric energy in the circuit, while the strains induced in the PZT patch will also generate electric energy. In this paper a simplified two-degree of freedom lumped mass model is studied for the analysis of the proposed hybrid harvesting system for harmonic vibration input. Attempts are made to optimize the parameters of the model to get maximum net power generated by the system.