PWM interface for piezoelectric energy harvesting

In this study, a wideband electric interface based on pulse width modulation (PWM) for piezoelectric energy harvester is investigated. The switching interfaces are used to increase the output power of energy harvesting devices for wide frequency range. It is shown that the energy harvesting technique can effectively enable harvested power to be the maximum possible value for a dynamic electromechanical system for all excitation frequencies. The proposed wideband interface is composed of a full bridge converter with PWM modulation. The piezoelectric voltage is adaptive to the vibration. In the final experiment, the PWM interface can harvested more energy in the case of multi-frequency vibration.