Comparison of Advanced Analysis Techniques to Traditional Methods

摘要

We report on two transmission lines that demonstrate the need for more sophisticated analysis of transmission systems. Topics covered include the stability of wood H-Frames, ruling span vs. finite element based sag-tension, and complete finite element line modeling as opposed to the modeling of structures, insulators and conductors in isolation. We demonstrate that traditional ruling span based sag-tension can be incorrect resulting in unexpected longitudinal loads and erroneous sags. We discuss a complete system approach that treats an entire line as a large structure, allowing the analysis to consider the effects of unbalanced line loading, structure flexibility and the resulting interactions between structures. We will conclude with a line that experienced flashover failure as a result of the interaction between flexible steel poles, unbalanced line loading and unstable hinged braced post insulators.