Research On Delay Of Wireless Sensor Network In Transmission Line Condition Monitoring

Transmission lines are important parts of power system. It makes significant sense tomonitoring the condition of transmission lines. As one of the key technology of internet ofthings, wireless sensor network (WSN) has drawn worldwide attention. The application ofWSN in condition monitoring transmission lines can improve its intelligent level remarkably,but in application of WSN at present, many key technical issues are needed to be solved. Thus,to research the application of WSN in transmission lines condition monitoring, this papercarry out the work from several issues which are architecture, topology and node deployment.First, the research status of WSN is analyzed. The basic structure and characteristics ofWSN are introduced. Combining the application background of transmission lines conditionmonitoring, the architecture of transmission lines condition monitoring based on WSN isproposed. Each layer’s constitution and functions are present. In the end, Communicationinterface of the architecture and networking strategy are studied.Then, the topology of WSN applied in transmission lines condition monitoring arestudied, three kinds of topology are proposed which are flat ribbon type, long chainhierarchical type and heterogeneous hierarchical type. Their performance index such asreliability, end to end delay, packet loss rate and throughput are compared. The heterogeneoushierarchical type, which shows better performance on end to end delay, is chosen to beresearch object, and the model of its network delay bound which can be used to evaluate thereal time performance is built by holistic method based on network calculus. Considering theMAC protocol based on channel competition, the model is amended.Then, after analyzing the influence factors of heterogeneous hierarchical network’s delaybound, the real-time optimization problem of heterogeneous hierarchical network istransformed into combinatorial optimization problem aiming at minimize the delay bound.Considering the characteristics of the combinatorial optimization problem, an optimaldeployment method based on local research algorithm is proposed. The way to generate initialsolution and neighborhood space and the strategy to search the neighborhood space aredesigned. Using the reduction to absurdity, the optimal deployment method is proved to beable to acquire the global optimal solution. But the optimal deployment can’t solve theproblem that some area exist heavier network load in single layer chain network, so themulti-layer networking strategy that divide the network into many independent layers throughchannel division is proposed to shunt the local heave load.Finally, based on the geographical environment feature of a transmission line in Yunnan province, a simulation scene is built to verify the optimal deployment method and themulti-layer networking strategy. The results indicate that the two real-time optimal methodscan realize cooperation, and optimize the real-time of heterogeneous hierarchical networkeffectively.