Synchronous Electric Charge Extraction for multiple piezoelectric energy harvesters

Abstract

This paper presents a power management circuit implementing a Synchronous Electric Charge Extraction on piezoelectric energy harvesters based on a flyback architecture. The novelty of this circuit lies in its ability to handle multiple energy harvesters operating at different frequencies and different output voltages with a single and standard flyback coupled inductor. The power harvested by the various scavengers is stored in a single and mutual storage capacitor. By construction, the power management circuit is capable of dealing with high input voltages (>100V). Its power consumption is about 1.15μA@3V per energy harvester and its conversion efficiency reaches 83%; its good operation has been validated by simulations and experiments on two vibration energy harvesters.