Research On Charging Strategy Of Rechargeable Wireless Sensor Network In Underground Coal Mine

The underground mine environment is harsh,and continuous and stable monitoring is a necessary requirement to ensure safe production in mines.Wireless sensor networks(Wireless Sensor Networks,WSNs)deployed in coal mines can provide more safe and reliable working conditions for coal mining workers,but the sensor nodes The problem of limited energy has always hindered the development of traditional WSNs,especially in mine tunnels that require sensor nodes to continue to work.In the past few years,wireless rechargeable sensor networks(Wireless Rechargeable Sensor Networks,WRSNs)have been proposed and widely studied,and WRSNs can effectively solve the problem of node energy supply.In WRSNs,to ensure that sensor nodes continue to work steadily,the core issue is how to design charging strategies.Aiming at the special environment of mine roadway,this paper applies wireless charging technology to traditional downhole WSNs,analyzes the one-dimensional and two-dimensional conditions of coal mines,and studies the charging strategies suitable for mine wireless rechargeable sensor networks for different situations.First of all,this paper studies and analyzes the disadvantages of the underground application of traditional charging strategies,that is,multiple charging cars working in parallel in a long and narrow coal mine roadway are likely to cause congestion.Moreover,according to the current one-dimensional situation,Some charging strategies,considering that they cannot efficiently complete the charging task,the energy utilization rate of the charging is not ideal,and the time spent in the charging round is not satisfactory,on this basis,we have proposed a suitable mine roadway Distributed mobile collaborative charging strategy,and then through a large number of simulation experiments,analyzed the impact of different node numbers,MC moving speed,charging efficiency,etc.on energy utilization.Next,this paper studies and analyzes the disadvantages of the traditional on-demand charging strategy that only considers the time and space in two-dimensional situations.The most typical one is the NJNP charging strategy.This is a preemptive charging strategy.For the factors it ignores,this paper proposes In order to find the shortest path of traversing all nodes in the network,a multi-module cooperative charging strategy based on Dijkstra algorithm is proposed.The multi-module cooperative charging strategy first defines the charging topology between nodes according to distance,energy and life.Due to the two power limitations of MCs battery capacity,MCs cannot charge all sensor nodes at the same time.On this basis,two different charging scheduling methods are proposed.In addition,in order to extend the service life of the entire WRSNs,two charging strategies were designed to increase the energy consumption and service life of the WRSNs.Multi-module collaborative charging can be divided into three stages: charging topology,charging scheduling and charging strategy stage,each of which considers multiple influencing factors: charging topology stage defines the charging range and builds charging topology;charging scheduling stage selects nodes for charging;multiple Two collaborative charging methods based on Dijkstra's algorithm are designed for the collaborative charging of the module;the energy requirements of the nodes are calculated in the charging strategy stage,and the final candidate charging node is determined.Then through a lot of simulation analysis of the cost and energy utilization of the strategy.The thesis contains 33 pictures,2 table and 80 references.