Bidirectional Thermoelectric Assisted Synchronous Charge Extraction Circuit Based on Buck Structure for Piezoelectric Energy Harvesting

Abstract

Energy harvesting technology is currently a research hotspot, which can effectively solve energy supply problems in fields such as wireless sensor networks, wearable devices, and smart homes. An energy harvesting system using a thermoelectric generator (TEG) for energy assistance of a piezoelectric transducer (PZT) is proposed. It employs a synchronous charge extraction circuit based on a buck structure (BUCK-SECE), which uses thermoelectric energy to inject energy into the piezoelectric element in both directions to boost the initial voltage of the BUCK-SECE, increasing its output power. The experimental results demonstrate that the utilization of thermoelectric energy can increase the output power of BUCK-SECE by a factor of 3.3 under low-vibration conditions and by a factor of 0.8 under high-vibration conditions. Therefore, the proposed energy harvesting system in this article can effectively enhance the output power of piezoelectric energy transducers and yield desirable performance in real-world applications.