Research And Design Of Multi-source Energy Harvesting DC-DC Converter

More than ten years witnessed,it is used to achieve a significant advancement of energy harvesting techniques for independent charging electronic devices and self-powered wireless sensor nodes.In order to overcome the energy of a single energy harvester,a hybrid energy harvesting system has been proposed in recent years.The mixed harvest includes not only harvesting energy from a variety of sources,but also converts energy into electrical energy through a variety of types of conductive mechanisms.The reasonable mixing of a variety of energy conversion mechanisms can not only improve the spatial utilization,but also significantly increase the power output.In addition to the conductive mechanism,the hybrid energy harvesting system requires an appropriate power integrated circuit to summarize the output power of each collector and pass to the load.To this end,this paper designs a multi-source energy harvesting DC-DC converter,which can harvesting three kinds of environmental energy at the same time,improves the singleness of a single energy source application,realizes the real-time energy harvesting conversion work in multiple scenarios,and integrates the self-starting circuit within the system,realizes the system’s own self-sufficient power supply without an external battery,and provides electrical energy to the wearable device.This paper introduces the common energy sources,common structures of energy conversion systems in wearable devices,and designs a single inductive multi-source energy harvesting system,using mixed modulation of pulse frequency and width,using different asynchronous logic control at the input and output ends,achieving better system stability,as well as a variety of energy mixing effects,and better applying it to the multi-source environmental energy harvesting system of wearable devices.The control policies suitable for use in multi-source energy harvesting systems are proposed,and adaptive asynchronous clock controls are used for input and outputs,and the adaptive maximum power point tracking is implemented for input sources,different frequencies are generated according to different input sources.Inductively charging signals of different duty cycles,enabling inductors to operate under intermittent mode under different input conditions;when the load energy is sufficient,the system stores excess energy to the energy storage capacitance,supply the internal use of the system,when the output When the end does not require energy,the system will enter the sleep state,waiting for the output of the output to be able to wake up.The system response requires the input source and the feedback signal of the output voltage to be completed,so the comparator for determining the input signal and the output signal is particularly important,and therefore,it is designed for folded low voltage,low power,low power,low power,low work,low work design The delayed comparator is only 0.15μW,which can be set to different hysteresis intervals according to different input sources or load voltages,further reduce the internal power consumption of the system.The multi-source energy harvesting of this paper uses 0.18μm CMOS process design,focusing on the design of control strategies for multi-source energy harvesting systems and low power consumption of system modules.The simulation results show that the system can achieve a low voltage self-starting of the minimum of 200 m V,and provide a 1.4 V stable output voltage in the case of normal power supply to the system 1 V,the highest conversion efficiency is 76.43%@R_load=10 kΩ,in sleep The average static power consumption of the system in the state is 2.38μW.