On-line Monitoring Communication System For High-voltage Transmission Line

“Smart grid” is the trend of future power system and it requires that all components of the grids be monitored for the purpose of maintenance. High-voltage transmission lines are key components of power system because of the high voltage ranking and wide service ranges; thus it is necessary to build online monitor system in order to efficiently acquire real-time transmission line status data.It is advantageous to integrate wireless Mesh networks with existing fiber-optical networks in the construction of transmission network based communication system as Mesh network technologies have been developed and applied. In this diseration, several topics will be addressed. Firstly, the demand of on-line monitoring communication system for high-voltage transmission line will be analyzed; the architecture of wireless Mesh communication system will be studied; self-repairing, reliable wireless Mesh transmission line communication system will be proposed; the design of the backbone-link routing and the wireless Mesh nodes structure of the wireless Mesh communication system will be proposed. Secondly, since the communication radio frequencies between Mesh devices are within microwave range, Mesh transmission model and measures of preventing overreach interference will be proposed based on the analysis of factors involving visibility-range microwave transmission. Thirdly, automatic selection of optimal locations along transmission lines and suspension heights of Mesh stations can be implemented with Matlab programming; the optimal suspension heights of Mesh stations are calculated with the idea of viterbi, which has much less calculation loads and is thus much more time-efficient compared with traditional algorithms for calculating antenna heights. Theoretical Mesh designs for two real transmission lines are given by this new algorithm with the data provided by China Southern Power Grid; some Mesh device parameters and locations are determined. Finally, two options of power supply for Mesh and other monitoring devices are proposed considering the rainy climate of Guizhou Province(the location of this project). One plan is combining transmission lines with lasers and batteries; the other is to combine photo-volt electricity with batteries.