Design of Transmission Line Tower using Angle and Tube Section

Abstract

A high voltage transmission line structure design is characterized by the special re- quirements 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. In the present study, main focus is to analyze and design two different capacity 400kV and 765kV double circuit transmission line towers. A comparison of design using an- gle and tube section is carried out. Geometrical layout of the transmission line tower is derived keeping in view electrical clearance. Gravity and Lateral loads are considered for analysis and design as per IS:802-1995. Wind loads on conductor and tower body are calculated by developing excel sheet. Computational model of tower is developed using STAAD Pro and analysis is carried out to obtain member forces. Design of members as well as member connections are carried out as per IS:800-2007 using excel sheet. A design comparison is made among tower designed using angle section and tube section with respect to de ection, weight of the total structure and cost of tower. It is found out that suspension tower have more de ection compare to tension tower. Tower with angle section have around 38% higher steel compare to tube section in suspension tower and around 25% higher in tension tower.