Store, Supply, Extract and Recycle: A Boost/Buck Reconfigurable Converter for Thermal Energy Harvesting

The extracted energy of the thermal energy harvester circuits are affected by the input and output power status. A boost and buck reconfigurable harvester circuits with store, supply, extract and recycle modes are proposed in this paper to harvest the power from TEG at any possible chances. In addition, maximum power point tracking and zero current switching are also customized for the reconfigurability. Moreover, Colpitts oscillator and Dickson charge pump based startup circuit are adopted for millivolts startup. Simulation shows that the proposed design shows end-to-end conversion efficiency of 86% in conventional boost configuration as well as 75.3% in buck configuration with minimum startup voltage of 7mV. In extract mode, up to 27% total power can be harvested from TEG even configured as buck converter.