This paper presents a study of a piezoelectric energy harvesting circuit based on low-power-consumption synchronized switch technology. The proposed circuit includes a parallel synchronized switch harvesting on inductor interface circuit (P-SSHI) and a step-down DC-DC converter. The synchronized switch technology is applied to increase the conversion efficiency of the circuit. The DC-DC converter is used to accomplish the impedance matching for different loads. A low-power-consumption microcontroller and discrete components are used to build the P-SSHI interface circuit. The study starts with theoretical analysis and simulations of the P-SSHI interface circuit. Simulations and experiments were conducted to validate the theoretical analysis. The experimental results show that the maximum energy harvested by the system with a P-SSHI interface circuit is 231 μW, which is 2.89 times that of a system without the P-SSHI scheme. The power consumption of the P-SSHI interface circuit can be as low as 10.6 μW.
Low-Cost Fully Autonomous Piezoelectric Energy Harvesting Interface Circuit with up to 6.14x Power Capacity Gain
