Applicability of Dickson Charge Pump in Energy Harvesting Systems

Anotace: Energy harvesting methods provide very low instantaneous power. Accordingly, available voltage levels are low and must be increased so that an energy harvesting method can be used as a power supply. One approach uses charge pumps to boost low AC voltage from energy harvester to a higher DC voltage. Characterized by very low output current and a wide span of operating frequencies, energy harvesting methods introduce a number of limitations to charge pump operation. This paper describes and models behavior of Dickson charge pump in energy harvesting applications. Proposed Energy Harvesting model is evaluated and compared with Standard and Tanzawa charge pump models and with measurement results. Based on the proposed model, the conditions that need to be satisfied so that a charge pump can reach maximum power point of energy harvesting system are defined. Parameter selection method optimized for maximum power point is presented and is experimentally validated.