The vital factor of any power transmission line transmission tower. Main parameters of high voltage transmission lines depend on voltage level. There are various types of towers use for electrical power transmission lines and the major types of Transmission towers can categorized as bellow.
1. Suspension Tower
2. Tension Tower
3. Transposition Tower
4. Special Tower
Suspension Towers
Suspension towers are on the straight line of transmission line it may vary maximum to degree of 5 angle. The suspension towers design to carry the only weight of the conductor in straight line position. Most of towers in any transmission line is fall into this type of tower category and construction cost of suspension type transmission lines are much cheaper compare to other types of transmission lines.
Tension Towers (Angle)
Tension towers use at locations where the angel of deviation is more than degree of 5. Tension towers are also known as angle towers and these type of tower are designed to take the tension load of the cable. Tension towers are mostly sued for turning points and for the section isolate locations.
The piece of line form one angle tower to other angle tower is known as section and length of the section may vary and depend on the geographical location. All the towers in between the section is suspension towers. Suspension towers are lightweight and much economical compare to angle towers.
Tower can divide in to two categories and Tower type are also can be categorized according to angel of deviation in location of appropriate towers. The types of tension towers due to angle of vary are mentioned in bellow.
0-10 degree tension towers (TD1)
10- 30 degree tension towers (TD3)
30-60 degree tension towers (TD6)
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Transposition towers are specially use for transpose the conductors of three phase line . Transposition arrangement also called as span transposition. These type of towers are widely used in long transmission line. These types of towers are much less use in recently. Major idea behind transposition is the change the three phase according to determined arrangement to obtain better performance in Transmission line.
Special Towers
If we consider on the height of transmission tower , height of all towers in same transmission line are not same. Tower of different heights obtained by using body extension and leg extension. Span between towers are not same as everywhere in same transmission line due to different geographical location. There are so many design parameters we have to consider while we are laying a transmission line in certain area. The safety is key measure and the relativity factor is also important for Transmission line.