An Innovative Controller to Increase Harvested Energy

This paper proposes an innovative energy-harvesting controller to increase energy harvested from vibrations. Energy harvesting is a process that removes mechanical energy from a vibrating structure, which necessarily results in damping. The damping associated with piezoelectric energy harvesting suppresses the amplitude of mechanical vibration and reduces the harvested energy. To address this critical problem, we devise an energy-harvesting controller that maintains the vibration amplitude as high as possible to increase the harvested energy. Our proposed switching controller is designed to intentionally stop the switching action intermittently. We experimentally demonstrate that the proposed control scheme successfully increases the harvested energy. The piezoelectric voltage with the proposed controller is larger than that with the original synchronized switching harvesting on inductor (SSHI) technique, which increases the harvested energy. The stored energy with our controller is up to 5.7 times greater than that with the conventional SSHI control scheme.