Research On Energy Management Of WSN Node Based On Photovoltaic Energy Supply

As a new information acquisition and processing technology,wireless sensor network(WSN)has broad prospects for development,relying on their real-time monitor,sense and collect the information about the monitored objects in the network distribution area.However,the limited battery capacity still restricts the rapid development of WSN.Self-powered sensor nodes bring hope to the development of the WSN by convert the energy in the environment into electrical energy and ensure the long-term operation of the node.However,the immaturity of technology makes the development of self-powered sensor networks still face many difficulties.So in the actual layout has not yet reached the point of maturity.Aiming at these problems,the maximum power point tracking(MPPT)and energy management of self-powered sensor nodes are the main research directions in this paper.This article first elaborated the self-powered wireless sensor network research status at home and abroad.Then analyze the characteristics of the energy storage module and establish the simulation model of the output characteristics of the photovoltaic cell.According to the climate of northern Guangxi and design requirements,complete the energy supply and energy storage module selection.As a nonlinear finite power source,the output characteristics of photovoltaic cells are not only affected by their own performance,to a certain extent,but also by the external work environment.Hence,to ensure that the node maximum power point tracking in order to ensure the node a higher energy supply efficiency.By summarize the MPPT method,analyze the MPPT method which suitable for self-powered sensor network to complete the current observation circuit design.As the energy storage module,the lithium battery and super-capacitor has different advantages and disadvantages,different charge and discharge energy management methods plays a decisive role for the life of the energy storage module.According to the different relationship between energy supply module and energy storage module,establish the energy flow model,design energy management circuit,and build PC monitoring interface.The weather in the natural environment changes all the times,ensure the node works in the energy-neutral operation module to ensure better quality of service.In order to ensure long-term stable work of nodes,introduce the concept of neutral work interval and constrained the energy management conditions.The weighted energy prediction algorithm based on the correction value is used to overcome the prediction delay caused by the weather change and improve the accuracy of the energy management scheme.In this paper,the method of combination the experiment and simulation is uesd to verify the design.Verify the comprehensive performance of energy supply circuit through the circuit efficiency analysis and laboratory experiment.Verify the reliability of the energy flow model through different situation simulation.Verify the overall system performance by outdoor testing.The experimental results show that the system designed in this paper is in accordance with the theoretical situation and satisfies the actual demand,and can meet the requirements of the actual environment in northern Guangxi.