High Voltage Transmission Line can describe simply set of wires which connect electrical power generation plants to distribution substations.Transmission line is main media of transferring electrical power; Bulk transfer of electrical power is usually transmitted through overhead power line.Underground High Voltage Transmission Line and Overhead power transmission are the common two types of power transmission apply in whole world. Underground power transmission cost is much higher than the over head transmission lines so by considering cost factors most of electrical suppliers tend to go for overhead transmission lines.
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Step up step down transformer
In transmission system electrical power are step up and step down at different point for the most efficiency. There are various types of transmission tower structures were use according to the terrain in existing area and infrastructure.Normally Transmission line system can categorized mainly as High-voltage transmission lines and Low-voltage transmission lines.Normal Voltage clarification of those lines were 400 kV,220 kV and 132 kV ,but there are more other voltage types use for transmission line in different countries. In every country got different transmission system according to their necessity.
The Voltage which create in generating plant increase by using step up transformers and then feed to the Transmission line. The purpose of the increasing the voltage using step up transformers are to travel longer distance with less electricity losses.Transformers in distribution end cut the electrical energy to lower voltages to create suitable level of energy for short distance in distribution areas.The transformers which use in lower voltage end call as step down transformers.
High Voltage Transmission Line Classification According to the Distance
Transmission Line Type
Transmission Line Length
Short transmission line
up to 80 km
Medium transmission line
between 80km to 160 km
Long transmission line
more than 160 km
Application of High Voltage Transmission Line Works
Transmission line tower heights and weights are relatively proportional to transmission voltages which means when for higher voltage transmission line height and weight are great then lower voltage transmission lines.
30 to 40 percents of transmission line cost constitute the tower costs so by being highly effective and efficient in design and construction would become key factor to reduce to cost for transmission line.
Efficiency of Transmission Line
The main purpose of transmission line is to give a high-efficiency quality electricity to consumer.Since the purpose of giving high-efficiency electricity there would have several power losses and voltage drops in transmission system so the getting the efficiency of the transmission system is another vital factor in power system .
The efficiency of Transmission line calculate as Power deliver at receiving end divide by power sent from sending end and it multiply by 100% so we can get the percentage of the transmission efficiency.
Speed and Frequency of Transmission Line
The speed of electrical power traverse in transmission line is normally the speed of the light which is 3X108 m ⁄ sec.Frequency can different in various countries but the normal standard frequency of the power system is 50 Hz.
If we consider about power system in any country Transmission line do vital task of this whole process and having high performance transmission line will also lead to have a better power system in any country.