Design And Optimization Of Low Frequency Vibration Micro Energy Harvesting System

In the coming era of Internet of things,low-frequency vibration micro energy collection system has broad application prospects because of its green environmental protection,maintenance free and other advantages.The system is mainly composed of the former generation device and the latter power management circuit.In this paper,the research status of the former and the latter two levels of the system are investigated respectively,and it is found that the former generation device has the problems of low collection voltage and low power,while the latter power management circuit has the problems of low voltage utilization rate and unstable output voltage.In view of the above problems,this paper attempts to optimize the design of the front stage power generation device and the rear stage management circuit of the low-frequency vibration micro energy collection system.This paper first analyzes the performance requirements of the low-frequency energy collection system,determines the basic structure and dimensions of the system,and then carries on the mathematical modeling of the vibration power generation device according to the dimensions.By simplifying the mathematical model and traversing the optimization,this paper finds an optimized structure of double magnet vibration power generation device.Compared with the traditional single magnet structure,under the premise of the same vibration environment,half of the winding material and the same mass and volume of the magnet,the double magnet structure can still double the power generation;at the same time,the rule that "changing the winding diameter will only change the open circuit voltage,but not the output power" is also obtained under the same winding space,which provides guidelines for the design of power generation devices.In the face of the shortcomings of the traditional power management circuit,this paper proposes a series parallel automatic voltage stabilization solution.Through a simple single voltage closed-loop,the circuit realizes the automatic switching between series mode and parallel mode,so that the input voltage can work in a wider range,and the utilization rate of energy is improved.Finally,the above theory is verified by experiments.The experimental results show that the theoretical analysis and design method given in this paper are correct,and the low frequency vibration micro energy collection system designed and optimized in this paper is effective and feasible.