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No neutral is necessary, because the transmission line's line currents are roughly balanced and, so, the phasor sum of those currents will be relatively insignificant, rendering the need for a neutral conductor to be an unnecessary expense.
In practise, for most transmission towers, each of the three 'lines' comprises not just a single conductor but, rather, a number of conductors which are bundled together in order to reduce electric stress surrounding the line. The number of conductors per bundle increases with transmission voltages. In the UK, for example, 400-kV transmission lines normally comprise bundles of four conductors, whereas 275-kV transmission lines normally comprise bundles of two, and 132-kV lines just one.
Running along the top of transmission towers is an earthed conductor, called a 'guard conductor', whose function is to protect the lines from lightning strikes during electrical storms.
Many transmission towers also have two, separate, three-phase circuits -one circuit on each side of the tower.
But, definitely, no neutral!
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To reduce power losses in transmission lines the voltage is made?
Much higher.
How do you reduce radiation loss in transmission lines?
Transmission loss reduce by using 1) higher diameter conductor (R = q l / a) or specially maded low loss conductors 2) using energy efficient equipment such as low loss transformer 3) twisted conductors instead of solid 4) proper monitoring and control of transmission eqipment 5) use of high temperature super conductors ....etc
List some conductors made of metal?
Anything made of a metal or metal alloy will be a conductor. The most common are copper (indoor wiring) and aluminum (power lines and transmission cables).
What is transmission in telecommunication?
ha ha, why not search from the web? ha ha, why not search from the web?
What is the difference between overhead transmission line and under ground transmission line?
Um. One is hung above your head on telephone poles and the other is ran underground in conduit? Unless you meant something else? Also burying cable costs ~10 times as much for transmission lines as overhead. It also usually has a lower power carrying capability, since it cannot dissipate heat as readily as an overhead conductor.
Why there is no neutral conductor in power transmission lines?
Using a distribution system (e.g. 11 kV in the UK) as an example, the primary of a three-phase distribution transformer is delta-connected, which requires to be supplied by three line conductors. So a neutral conductor is superfluous.
There is any need of use neutral wire in transmission lines of very high voltages say 440 kv?
Transmission lines are fairly-well 'balanced' in the sense that the magnitude current flowing in each line conductor is roughly the same (this is due to deliberate balancing applied to downstream loads). So there is no real need for a neutral, whose function would be to act as a return conductor the phasor-difference between those line currents. Accordingly, transmission 'power transformers' secondaries are normally delta-connected (there is no neutral in a delta-connected system). Furthermore, one of the main advantages of three-phase, compared with single-phase, is that there is a substantial saving in the volume of copper needed -this advantage would be eliminated if a neutral conductor was required.
What are the round ball like structure on the topmost line in power transmission lines?
The topmost conductor in a transmission line is called the guard conductor; it is an earthed (grounded) conductor that links the metal support towers. Its function is to protect the transmission lines against lightning strikes. The coloured balls that are sometimes seen distributed along the guard conductor are intended to make the lines easier to see in those areas where aeroplanes might be flying -they are often seen on lines in the vicinity of airfields. They are also used in areas, such as nature reserves, to make the lines visible to large birds.
Why copper is used in electrical transmission line?
Copper is a good conductor and is fairly strong. It generally is not used in power transmission lines due to cost - generally aluminimum is used.
What conductor does not carry current during normal operation?
In a three-phase power transmission system, the neutral conductor does not carry current during normal operation when the system is balanced. The neutral conductor is only used to provide a return path for unbalanced currents in the system and does not carry current when the system is operating under balanced conditions.
What situations use copper as a conductor?
Phone lines, power lines, and household cables.
When lines of force are cut by a conductor you have?
When lines of force are cut by a conductor, an electromotive force (EMF) is induced in the conductor according to Faraday's law of electromagnetic induction. This induced EMF can drive an electric current to flow in the conductor, resulting in the generation of electrical power.
Why is energy lost in power transmission lines?
Increase the voltage in the lines.
How do you adapt a single phase 230V 50 Hz machine having total power 5 KW to a three phase system with no neutral?
The earth can be used as a neutral provided the earth is connected to the supply of the network and any of the 3 phases of the supply as a life. All electric supply networks use only 3 HT transmission lines and derived the neutral at the end from the star connection of the step-down transformers secondary windings that is also connected to earth in most countries. There is no neutral running from the power station to the end users step-down transformer, so the earth is a neutral. For more info look at the following link where one can see on the photos of the transmission line only 3 lines is visible. http://en.wikipedia.org/wiki/Three-phase_power See http://en.wikipedia.org/wiki/Ground_and_neutral: Since the neutral point of an electrical supply system is often connected to earth ground, ground and neutral are closely related. Under certain conditions, a conductor used to connect to a system neutral is also used for grounding (earthing) of equipment and structures. Current carried on a grounding conductor can result in objectionable or dangerous voltages appearing on equipment enclosures, so the installation of grounding conductors and neutral conductors is carefully defined in electrical regulations. Where a neutral conductor is used also to connect equipment enclosures to earth, care must be taken that the neutral conductor never rises to a high voltage with respect to local ground.
What does aluminum foil do to electricity?
Aluminum is a good conductor of electricity. While it won't actively "do" anything to electricity, it will pass electric current if it used as part of a circuit. Aluminum is used in overhead power transmission lines as it is lighter than an equivalent copper conductor.
It transmits electricity like copper?
Aluminum is a good conductor of electricity similar to copper. It is often used in power transmission lines due to its conductivity and lower cost compared to copper.
What is the difference between a neutral wire and a hot wire?
In alternating-current systems, we don't have a 'positive' and a neutral conductor, but a 'line' and a neutral conductor.The neutral conductor is connected to the earth and, so, has a potential of approximately zero volts.The line conductor, on the other hand has a potential of approximately 230 V (in Europe) or 120 V (in North America) with respect to the neutral conductor. For this reason, line conductors are frequently referred to as being the 'hot' conductor.
