不均匀覆冰工况下直线塔失效预警技术

以某实际500 kV直线塔为例,基于覆冰监测终端的绝缘子串拉力测量系统对杆塔安全状况进行评估。本文提出了一种考虑两侧档距耦合作用的不均匀覆冰绝缘子串拉力计算方法,得到了多种覆冰工况下的绝缘子串拉力和倾角。通过有限元仿真进行验证,该方法误差不超过1. 98%。建立了直线塔的有限元模型,分析了不同重力载荷和沿线路方向不平衡力组合下的临界失效情况,制定了分级临界失效曲线。分析了不均匀覆冰下该直线塔临界失效的冰厚范围。本文结合工程实际,对覆冰区直线塔失效预警研究具有一定指导作用。

Pre-Warning Technology of Straight Tower Failure Under Non-Uniform Icing Condition

Take a real 500 kV straight tower as an example,the safety status of the tower is evaluated based on the insulator string tension measurement system of the ice-coated monitoring terminal.This paper proposes a method for calculating the insulator string tension considering the coupling of both spans under non-uniform ice-coated condition,and obtains insulator string tension and inclination angle under various icing conditions.By finite element simulation,the error of the proposed method is less than 1.98%.The finite element model of the straight tower is established,and the critical failure conditions under different gravity loads and unbalanced forces along the line are analyzed,and the grading critical failure curve is drawn up.The ice thickness range of the straight tower critical failure under none-uniform icing is analyzed.This paper combines the engineering practice and brings guidance for failure pre-warning of straight towers in icing areas.