Research On Dynamic Routing Algorithm Based On Artificial Cobwebfor Low-voltage Power Line Communication

Low Voltage Power line communication(LVPLC) over distribution networks has become one of the potential technologies to communicate information between end users and power providers. But the physical topology complexity, ambiguity and variability of distribution network, the diversity and sharing of physical medium, strong noise of the communication channel and so on, which lead to the low reliability of LVPLC, and directly affects its large scale applications in the construction of Smart Grids. Therefore, with the aspect of LVPLC dynamic routing, we selected intelligent meter reading system based on power line communication as application background, the novel method to improve the reliability of LVPLC was presented in this dissertation.The thesis analyzed the application status and research progress of narrowband PLC(NB PLC), high data rate narrowband PLC(HDR NB PLC), ultra narrowband PLC(UNB PLC) and broadband PLC(BB PLC) used in high voltage, medium voltage and low voltage in smart grids. The results and research progress of establishing static and dynamic routing via networking to improve the reliability of LVPLC were analyzed, from which we summed up the problems and shortcoming of current technology. Based on the analyzing of the physical structure characteristics of LVPLC network, logical network model, combined with the structure of natural spider web, we presented a novel artificial cobweb network and mathematical model with the LVPLC characteristics. The communication principle of artificial cobweb was presented. The simulation results showed the communication feasibility of artificial cobweb routing model. According to the simulation results and actual networking needs, we selected the single layer artificial cobweb routing model as the LVPLC networking model.The thesis analyzed all terminal reliability of network based on combined Markov probability model and factor decomposition method in order to validate the reliability of aritificial cobweb applying to LVPLC. The calculation results show that the all terminal reliability of artificial cobweb network is much higher than other networks. We select the invulnerability degree as the standard, the invulnerability of artificial cobweb network is calculated, the results show that the reliability of artificial cobweb is much higher from invulnerability. Through the comparison of calculation and analysis, from two aspects of the all terminal reliability and invulnerability, we verify the connectivity reliability of artificial cobweb routing. The simulation results show that the artificial cobweb routing can guarantee the network connectivity, resilience and ability of anti disturbance, and prove the reliability of artificial cobweb routing used in LVPLC.The thesis presented the implementation method of artificial cobweb routing algorithm for bus type and tree type LVPLC network topology respectively based on reliability of artificial cobweb routing used in LVPLC. We presented an artificial cobweb center node selection algorithm based on Dijkstra algorithm. We applied artificial cobweb routing algorithm to bus type LVPLC network. The process of algorithm initialization was given in detail, the communication protocol was set up and the simulation and experiment were given. The implementation method of artificial cobweb routing algorithm for bus type was established, the delay characteristics of after networking network was analyzed in detail via simulation and experiment, and the implementation method of artificial cobweb routing algorithm was further improved, provide the reference for the engineering practice of LVPLC technology.To solve the problem of randomly generating “blind nodes” in the after networking network based on artificial cobweb, according to the node characteristics of multiple paths, we built a strong adaptability and good self organization local network structure, and established a perfect local routing reconstruction method and routing maintenance strategy. The routing reconstruction method can solve the “blind node” of the local network, avoid all nodes of the network participating in the routing reconstruction process and guarantee the communication efficiency and Qo S of artificial cobweb network further.Based on the completed artificial cobweb routing algorithm, in order to solve the problem of low optimization efficiency ant colony algorithm used in LVPLC, based on artificial cobweb method can divid LVPLC network into multiple hierarchical networks, an improved hierarchical ant colony routing algorithm based on artificial cobweb routing algorithm for LVPLC was proposed. Based on this strategy, hierarchical ant colony routing algorithm would find an optimal route in order to combine the base station and one of any node in the network. Also, this algorithm solved the routing optimization problem between low voltage power line backbone network and local area network, and provided a new method to improve the reliability of LVPLC. The simulation results showed that the algorithm can effectively extend the distance of the low voltage power line and improve the efficiency, which would provide reference for the engineering application.