Research On Structure Analysis And Management Of Power Transmission Tower

The power transmission tower is the important supporting part of the overhead power transmission line system. It supports the wire and other accessories. The health of the tower structure will affect normal operation of the entire power system directly. With the increase of the capacity of the national power grid, the transmission tower has some new characteristics, e.g. high-rise tower, flexibility, large-span and high voltage level. Therefore, the more reliable and less-costly tower is necessary according to the current development trend. The acquisition of the accurate distributions of the displacement and stress of the tower under variety of physical loads is the basic and crucial step of structural optimization. However, the tower is a 3D high-rise hyperstatic truss structure, and the tower together with the wire and other accessories constitute a very complex nonlinear dynamic coupling system. It is very difficult to obtain the mechanical response of tower.The paper describes the characteristics of power transmission tower structure and different environmental loads on the transmission tower. Some accidents of transmission towers due to the structural failure in recent years are listed and analyzed. The summary of current methods is given. The current status and development trends as well as the difficulties in the design and analysis of the towers are also summarized. The finite element modeling methods for the transmission tower coupling system are summarized and discussed. Based on previous work, the finite element modeling method is systematically studied. The nonlinear finite element analysis of the free-standing 220kv power transmission tower subjected to the ground surface deformation is carried out as an example. The detail and accurate distributions of the stress and displacement are obtained. The finite element modeling and structural assessment methods for the transmission tower system are studied in detail. Then, the accurate stress and displacement components are obtained, and the health status of the structure was evaluated. Based on the results, the strengthening scheme for the tower is given. And the structural analysis is carried out to verify the validity of the reinforcement scheme. Finally, for the practical problems, the paper discusses the scientific management and maintenance for power transmission tower.