Study On Monitoring The Icing-thickness Of Transmission Line Based On Mechanical Measurement

In the power system, the icing phenomenon of transmission line is very common. It can cause conductor galloping, tower falling down, insulator flashover and communication interruption, which greatly affect the safe operation of power system, and result in great economic loss and a certain degree of social influence. Therefore, mastering the icing situation of transmission line real-time has important practical significance and guidance to ensure the safe operation of transmission lines and improve the safety and reliability of power system.To measure the icing of transmission line on-line a new method is designed in this paper, which is based on mechanical measurement of tension section and tangent tower. An on-line monitoring system of transmission line icing is designed, in which, the axial tension, the inclination angle and the tension and excursion angle of hang insulating string are collected by the tension and angle sensor between the iron tower and the insulator string are transported to the control centre of power system through GPRS and Internet network firstly, and then, the data is processed by the control centre of power system. The icing thickness can be gained by expert software. The type and configuration of tension sensor, angle sensor, GPRS module and power device are designed according to the characteristics and requirements of the proposed monitoring system in this paper.This paper porposes the model of calculating conductor icing thickness by the axial tension, the inclination angle and the tension and excursion angle of hang insulating string in detail, and provides corresponding formulas. An experiment is conducted to verify the method. The absolute errors of icing thickness of conductor between calculated value and antual value of one conductor experiment are -0.21~0.11 mm, the percentage of calculation errors are -4.20%~1.10%. The max percentage of calculation errors of icing thickness between calculated value and antual value of three conductors experiment are respectively -4.60%,3.40% and -3.40%, The result shows that the proposed method performs well in many conductors icing thickness calculation. The result of one conductor and three conductors show that the proposed method performs well in icing thickness calculation.,which infers the method can be used to on-line monitor and calculate icing-thickness on transmission line.