Matrix synchronized switch harvesting on inductor (M-SSHI) interface circuit for piezoelectric and thermoelectric energy harvesting

Abstract

A novel interface circuit called Matrix Synchronized Switch Harvesting on Inductor (M-SSHI) is proposed. Multiple Piezoelectric Transducers (PZTs) and Thermoelectric Generators (TEGs) are arranged in an extensible matrix structure for energy harvesting with a single inductor. At the peak value of the PZT voltages, the synchronized switches are turned on so that the energy from the PZTs and TEGs can be extracted simultaneously. With the cooperation harvesting mechanism, the lowest thermoelectric harvesting voltage is as low as 20 mV. Furthermore, the self-powered diode-less designs improve conversion efficiency. The peak harvested power of the PZT can reach 3.7 times that of the standard energy harvesting circuit. The thermoelectric harvesting efficiency can reach 76% at V_oc=100 mV.