A direct AC-DC converter integrated with SSHI circuit for piezoelectric energy harvesting

Abstract

In this letter, a direct AC-DC converter for piezoelectric (PE) energy harvesting is proposed, which integrates a Synchronous Switch Harvesting on Inductor (SSHI) circuit, to achieve a resistive impedance matching. An SSHI circuit intends to deal with high impedance of the PE transducer. Then, the converter working in discontinuous conduction mode (DCM), with relative high switching frequency, delivers the harvested energy into the load. The circuit is self-powered and can start even if the storage elements are completely drained. The experimental results show that the proposed circuit has better power extraction capability with a higher output voltage, compared with conventional SSHI rectifier under the same excitation.