Design and Implementation of a Direct AC-DC Boost Converter for Low-Voltage Energy Harvesting

In this paper, a direct ac-dc power electronic converter topology is proposed for efficient and optimum energy harvesting from low-voltage microgenerators. The converter utilizes the bidirectional current-conduction capability of MOSFETs to avoid the use of a front-end bridge rectifier. It is operated in discontinuous conduction mode and offers a resistive load to the microgenerator. Detailed analysis and modeling of the converter is presented. In such low-power applications, the power consumption of gate drive and control circuits should be minimal. In this paper, they are specifically designed to consume very low power. A suitable startup circuit and auxiliary dc supply circuit is proposed for the implementation of the converter. A low-voltage microgenerator is used to verify the performance and operation of the converter and the gate drive circuits.