Experimental Study Of Ice-shedding Jump Of Tower-line System Model Test

High voltage transmission lines is the lifeline engineering of national economic development, whose normal running is the guarantee of national economic construction and people's lives and property. However, due to the constant exposure to the outdoor, transmission lines frequently suffer from the challenge of harsh natural environment. Documents show that Overhead transmission tower-line system frequently get damaged because of the overload of icing and ice-shedding jump, making it great engineering importance to study on ice-shedding jump of transmission tower-line system to the safety running of transmission lines. The paper uses model test method to study on ice-shedding jump of the transmission tower-line system. The main work is completed as follow:(1)On the background of one 220 k V transmission lines project in Hunan province, and based on the dynamic similitude theory, a two-span transmission tower-line system model test in scale 1:20 is designed and built,(2) An icing and ice-shedding control system is designed, and taking advantage of absorbing and desorbing of iron which is caused by electromagnet, simulating the transmission lines' icing and icing-shedding. By using the method of programming to control the absorbing and desorbing of electromagnet to fulfill the different conditions, including: zipper-like ice-shedding and simultaneous ice-shedding of transmission lines, whole and ice-shedding.(3)Various ice-shedding jump tests are done based on the tower-line system model. The dynamic displacement and dynamic stress response of transmission lines in different conditions are retained by using the device of non-contact video tester. And by comparing the test data with simulation results, the two corresponds well.(4)According to the result of test study, the most hazardous ice-shedding condition of tower-line system is ensured, obtaining the quantitative or qualitative conclusions with regard to the change of parameters of transmission lines' jump height and the peak dynamic stress, which can provide for reference to the design of tower-line system.