Analysis and Design of Transmission line Tower

Abstract

A high voltage transmission line structure design is characterized by the special requirements to be met from both electrical and structural point of view. The electrical specifications decide the general shape of tower and height of conductor, ground wire and cross arms dimensions. Loads that are considered are wind load and dead load with appropriate factor of safety as per IS 802- 1995. In present study data is assumed in the initial stage for problem formulation. Layout of tower is finalized by drawing electrical clerance diagrams in Autocad. Wind loads on conductors and tower body are calculated manually using excel sheet. Tower is modeled in Stadd pro and loads calculated in excel are applied on tower in Stadd pro. Analysis is carried out and economical section is chosen in Stadd pro. Manual member design calculations are caried out using excel sheet.

The work undertaken is an attempt to understand and compare the effect of dif- ferent bracing pattern, geometry and materials in transmission line tower structure. Two different cases were taken to carry out the study. In the first case, quad bracing is provided instead of simple bracing and in second case a horizontal configuration of the tower structure with same loading data. Connection and foundation design is carried out manually in excel sheet. The conclusions were drawn on the basis of analysis, member design and foundation design carried out with the help of software as well as manually. Parametric study is carried out with comparison of parameters like defection, total weight of tower and cost comparision. Results shows that vertical configuration of tower with quad bracing shows lower weight as compared to simple bracing. Tower with horizontal configuration shows higher tower weight as compared to vertical configuration. Foundation design of tower with horizontal configuration is governing in terms of cost as compared to vertical configuration.