EVALUATING THE EFFECT OF SUPPORTING STRUCTURE LATERAL STIFFNESS ON SEISMIC RESPONSE OF HIGH VOLTAGE CURRENT TRANSFORMER

Lifelines are the facilities that the life in industrial and advanced societies is possible only by ensuring their appropriate and permanent operation and functioning. One of the most important lifelines is electrical power equipment which considering the effects of recent earthquakes in the world, high voltage current transformer, due to limitation of the materials used to manufacture the porcelain insulator part, are the weak and vulnerable parts of the electrical power equipment in earthquakes In this study, firstly, the seismic behavior of the structures and equipment of high voltage electrical substations and their behaviors in the past earthquakes have been investigated. One of these elements, which is the high voltage current transformer 230 kv (Figure 2) has been selected as an important and key element in the electrical power substat ion. Subsequently, the seismic vulnerability of the equipment due to changes occurred in lateral stiffness of the supporting structure has been studied more carefully. For this purpose, first, the primary data of the equipment, such as technical specifications, dimensions, weight, the elements used and the stiffness of each, etc., have been collected.Then, with using a finite element analysis software, this equipment has been modeled. The final model is created by joining different parts (Figure 3-a), the most important of which are: bottom box, top tank, porcelain insulator, top flange, bottom flange and members of the supporting structure , that the modeled shape of some of them are shown in Figure 3-b to 3-d. In the meantime, the parts of the bottom box, top tank, porcelain insulator, top flange and bottom flange have been modeled by solid and homogeneous elements through various approaches (Solid Revolve and Solid Extrude). Also, the members of supporting structure used have been modeled by the wire element.

کلیدواژه ها:

Lifelines ، Electrical power equipment ، High voltage electrical substation ، Seismic vulnerability ، Current transformer