Energy Harvesting System with A Single-step Power Conversion Process Achieving Peak Efficiency of 79.1%

Abstract

Energy harvesting interface circuit with a single-step power conversion process is presented in this paper. The energy harvesting system is at the interface between the ambient energy source and the load. The proposed energy harvesting system consists of two switching circuits, a step-up converter and a temporary storage element. Switching circuits regulate the output voltage level needed by the load as well as transfer the energy to the step-up converter and the load. One switching circuit achieves the energy source connection to the step-up converter while other switching circuit enables the energy transfer from the storage element to the load. The step-up converter is connected to the energy source through a switch in order to boost the low voltage at the output of the energy source to a higher level. The storage element is at the connection of the converter output to accumulate the energy. In order to verify the proposed energy harvesting system, the ambient energy source is emulated. The proposed energy harvesting system has been constructed using commercial off-the-shelf components (COTSs). The proposed energy harvesting system has been tested under various loads. The storage element charges from 3.3 V to 3.7 V; thus, the load is kept at the voltage level between 3.3 V and 3.7 V. Measured results indicate that the proposed energy harvesting system achieves a peak end-to-end efficiency of 79.1%. Results show the effectiveness of the proposed energy harvesting system in terms of a single-step power conversion process and a high efficiency.