Transmission Line Icing On-line Monitoring System

Transmission line icing which is caused by the weather of low temperature, ice rain, wet snow and frost will bring forth disasters, such as icing flashover, transmission line galloping, line breaking, and tower collapse. Therefore, it is great of significance to design a transmission line icing on-line monitoring system to guarantee the safe operation of power grid.Based on the analysis of the advantages and disadvantages of icing monitoring methods at home and abroad, we deduce a transmission line icing model based on insulator string tension and insulator string obliquity, and design a transmission line icing monitoring system, which consists of line icing monitoring unit and monitoring center, based onμC/OS-II , embedded technology, wireless communication technology, data acquisition technology. Data and images collected by monitoring unit are sent to monitoring center servers through the GPRS network. Icing information will be unfolded by expert software after analyzing the data.This thesis is supported by the key project of Shanxi Province Power Company, "Transmission line icing on-line monitoring system." And the framework of this thesis is organized as follows: (1) We analyze the development status of transmission line icing monitoring system at home and abroad and comparing them according to advantages and disadvantages of each icing monitoring methods. Thus, we propose a novel monitoring method.(2) The hardware circuit of the monitoring unit is designed, including a core of LPC2368 chip, wireless communication circuit, sensors data acquisition circuit, image acquisition circuit, memory circuit, watchdog reset and power management circuit, etc. A series of measures are adopted to reduce power consumption and resist interference.(3) The software of the monitoring unit is designed. A real-time multi-task operating systemμC/OS-II is transplanted to LPC2368, application tasks and application programming interfaces are also designed.(4) A transmission line icing model based on insulator string tension and insulator string obliquity is deduced, and icing prediction model is presented. The main function modules of the control center software are introduced.Transmission line icing on-line monitoring system has passed the examination review. The system has installed on the transmission lines of Yangquan Power Supply Company in April 2009. So far, the system works very well. In November 2009, the system monitored line icing successfully.