Research And Design Of Ultra-low Thermoelectric Energy Harvesting System With Real-Time Maximum Power Point Tracking Function

The age of 5G communication is coming,so the application scenarios of the Internet of Things（IOT）are becoming more and more complex.The battery-based power supply system has the disadvantages of high cost and inconvenient replacement and maintenance.At the same time,"Green Electronics" and " Carbon Peak and Neutrality Strategy" have been proposed,which makes energy harvesting from the environment as a new trend in Io T power supply.This thesis focuses on the research and design of ultra-low thermoelectric energy harvesting systems.The core functions of the design are self-starting under ultra-low voltage,maximum power point tracking,and output voltage management.The self-start circuit designed in this thesis can make the system start up under weak energy source,and avoids using any external power supply and super storage capacitor.Different from the traditional maximum input power point tracking strategy,this thesis innovatively proposes a maximum output power point tracking strategy,which considers the energy source extraction efficiency and the conduction efficiency of the power converter,and an output power representation scheme with low power consumption and high precision is proposed.In addition,the output voltage management circuit is designed at the end of the energy harvesting system,so that the system output is stable and has load capacity.Sub-module circuits are designed for low power consumption.The specific system mainly designs a self-start circuit with an oscillator and a charge pump as the core,a maximum output power point tracking module with a sample and hold circuit as the core,and a reference and LDO module as the core output voltage management module.The specific circuit design of the system realizes low power consumption of the architecture and low power consumption of control which is the sub-circuit is designed with a low-power architecture and the sub-module is controlled to work only at a specific time through the system control signal.In this thesis,the Spectre simulation tool is used to build the sub-circuit and the overall topology circuit,and the simulation and verification of the sub-circuit and system are carried out based on the 180 nm BCD process platform.The verification results show that the circuit modules designed in this thesis all achieve the corresponding functions and indicators under low power consumption.The system can realize self-starting under the power supply of an energy source as low as 100 m V,and output a stable voltage of 1.2V.High-precision maximum output power point tracking can be achieved under the conditions of different energy source voltages and different energy source internal resistances,and the efficiency of the energy harvesting system can be as high as 94.33%.