Design And Implementation Of Wireless Sensors Networking Powered By Energy Harvesting

With the advantages of low-cost,easy-installation and flexibility over traditional communication technology,wireless sensor network has become an important part of the next-generation electric power system—smart grid.However,the harsh environments of electric power system has made big challenges to the WSN communication reliability in smart grid application.Due to the limitation of harvesting energy,it's also very important to make deep considerations about the energy-efficiency of WSN algorithms.Base on the application environment and energy constraint,we proposed a wireless networking scheme used for device temperature measurement in electric power system,that is,the customized SUB-G networking protocol is adopted between underlying sensors and routers to decrease the energy consumption of sensor nodes,and routers in the upper layer network use 2.4G ZigBee protocol in order to improve the stability and reliability of data transmission.Moreover,an improved Hybrid time synchronization approach is proposed to minimize the energy consumption by combining the advantages of RBS(Reference Broadcasting Synchronization)and modified TPSN(Timing-Sync protocol for Sensor Network).With the synchronized nodes,we can decrease the back-off time by modifying CSMA/CA algorithm.Furthermore,this article designs a routing protocol aimed at decreasing packet error rate(PER)during communication for ZigBee network.Simulation results demonstrate that the Hybrid algorithm can decrease the energy consumption significantly at the expense of an acceptable loss of synchronization precision.When dense networks consist of 350 sensor nodes,energy saving of the hybrid method over RBS and TPSN are up to 74%and 62%respectively.Moreover,CSMA/CA protocol at MAC layer increase the system throughput by 12.5%through using the dynamic back-off time scheme,and routing protocol at network layer achieves an average PER loss of 3.7%by employing the lowest PER path first scheme.In the end,TICC430 and TICC2530 chips are utilized to evaluate the networking function,communication performance and energy consumption of the designed system,which proves the proposed design of WSN is highly competitive for smart grid applications.