Human Motion Energy Collection And Management Based On Triboelectric Nanogenerators And Its Health Monitoring Application

With the rapid development of electronic and communication technologies,human society has entered the era of Internet of Things(Io T).In the field of Io T,real-time health monitoring holds vast market prospects,and wearable health monitoring devices have distinct competitive advantages due to their portability and real-time capabilities.The current devices face a significant challenge in power supply,which hinders its extensive use: the battery performance has a considerable impact on the user satisfaction.In response to this challenge,various efforts have been made by the academia and industry to find feasible solutions.One effective approach is to collect ambient energy and supply it to electronic devices after power management.An efficient approach is to harvest ambient energy and provide it to electronic devices through power management.Triboelectric nanogenerators(TENG)have unique advantages in collecting low-frequency and micro-scale mechanical energy,making them a crucial means of harvesting human motion energy.Based on the above analysis,this thesis focuses on the research and development of micro/nano energy harvesting technologies.It aims to design and optimize a hybrid nanogenerator that can efficiently collect human motion energy and integrate it with power management circuits,and ultimately constructs a self-powered wearable health monitoring terminal,thereby exploring an effective pathway for the engineering application of micro/nano energy.The main research contents are as follows:In Chapter 2,to meet the demand for capturing human motion energy,we have designed a novel wearable hybrid nanogenerator(WHG)consisting of a soft-contact triboelectric nanogenerator(SC-TENG)and a three-phase magnetic suspension electromagnetic generator(TPS-EMG).The soft-contact structure significantly improves the durability of the TENG unit,while the unique magnetic suspension structure endows the electromagnetic generator with advantages such as frequency-increasing effect,automatic resetting,and sensitivity to biomechanical motion.Through finite element analysis,the working mechanism of the WHG is further elucidated.In order to effectively manage the electrical output of the WHG,we have integrated a power management circuit using a commercial integrated chip.The three-phase rectification module in the circuit enhances the rectification efficiency by boosting the output voltage of the TPS-EMG.The chopping module reduces the matching impedance of the SCTENG while achieving maximum output within a single cycle.After integrating with a commercial low-power voltage regulator chip,the circuit enables various operating modes to address the power mismatch between the WHG and health monitoring applications.To demonstrate the application prospects of the WHG in real-time wearable health monitoring,we have combined low-power techniques to design and implement a self-powered health monitoring bracelet and a sustainable blood glucose monitoring system.This work offers a valuable insight for harvesting human biomechanical energy,and also presents a highly appealing self-powered approach for wearable medical health monitoring applications.Chapter 3 introduces a power management circuit tailored for TENG,to further enhance the specificity and adaptability of the power management circuit.The circuit delivers adjustable stable voltage to accommodate the load requirement while balancing the extraction efficiency and conversion efficiency of TENG energy.The power management circuit primarily consists of a charge matching and extraction optimization(CMEO)implementation module,an energy buffering module,and a low-power voltage regulation module.The CMEO implementation circuit utilizes MOS switches to improve the energy extraction efficiency of the TENG.The energy buffering circuit combines a Buck circuit with MOS switches to enhance the energy conversion efficiency of the TENG.The fully MOS-designed circuit lays the foundation for future integrated designs.The voltage regulation circuit achieves stable output voltage through a closed-loop chopping circuit.To minimize the overall power consumption of the circuit,we refined the whole circuit by streamlining the control loop of the switching power supply circuit,optimizing device parameters and other methods.Through the comprehensive optimization measures,we constructed a complete power management scheme tailored for TENG,and effectively enhanced the utilization efficiency of TENG energy.This solution provides a reference for the general strategies of TENG power management.