Dynamic Analysis of a Seven-span Power Transmission Line Section following Ice Shedding and Its Suppression Method

Abstract

Ice shedding is one of the major threats for overhead electric transmission lines and the suppression method of the resulting large amplitude vibration is essential to ensure the mechanical and electrical safety of lines in cold regions. The dynamic response of single and multiple span line under ice shedding have been well studies, while only few of previous studies focus on the suppression method. In this paper, a section of real 500 kV seven-span line section was modeled as case study with nonlinear finite element method. The static analysis of the case is conducted to obtain the initial static configuration after icing. Then, dynamic analysis is performed to obtain the influence of span length, ice thickness, ice shedding ratio on the dynamic response of the line section, in terms of midpoint displacement and suspension point tension. Finally, a kind of conductor vibration (due to ice shedding) suppression method with insulating guys is investigated, the results of which show that the proposed method can significantly reduce the dynamic effect of the line section following ice shedding. This study provides important information for the design of multi-span transmission lines and for the suppression of conductor vibration.