城沐一线500kV线路取消架空地线力学性能分析

架空地线的主要作用是防止雷电直击导线,但在冬季,由于架空地线线径较细,强度较低,多次因地线覆冰引发断线、跳闸事故,因此提出了取消重冰区500 k V线路架空地线的做法。使用有限元仿真工具ANSYS Workbench,以城沐一线500 k V线路三基杆塔为对象进行建模,对取消地线前后城沐一线的力学性能做了仿真计算。计算结果表明,在不同的覆冰强度下,取消地线后杆塔塔头及塔身主材所受拉力及应力都有所下降,提高了整个塔线体系在冬季运行的可靠性。结果可为冰区超高压电网的运行维护工作提供指导。

Analysis on the Mechanical Performance of the 500 kV Chengmu No.1 Transmission Line After Removing the Overhead Ground Wires

The overhead ground line can prevent the conduct line from direct lightning hit. But in winter, iced ground lines fracture and power supply interruptions happen for many times due to the thin diameter and the lower strength of the ground lines. Removing the overhead ground lines is a method to make a difference. In this paper, we use the finite element method (FEM) software, ANSYS Workbench, to simulate the mechanical performance of the 500 kV Chengmu No.1 transmission line with & without the ground wires based on the three towers model. The simulation result shows that the dragging force and the stress of the tower main material decrease after removing the ground Wires under different ice thickness. In this way, the reliability of the whole system of towers and lines is strengthened when running in winter. This paper can be an instruction on the daily job of the EHV transmission line in icing districts.