0
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.
Wiki User
∙ 13y ago
Add your answer:
Earn +20 pts
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.
Why is energy lost in power transmission lines?
Increase the voltage in the lines.
What is resonant and non resonant transmission line?
Non resonant transmission lines are longer than resonant lines. However, sometimes power is lost when power lines are too large, so the shorter ones may be favorable for certain frequencies.
Why must 2 wires run between a house and the electric power plant?
You must need 2 wires between a house and the electric power plant because one wire cannot hold that much power. If there is 1 wire the wire might burst. The burst can hurt anyone around there.AnswerIt's far more complicated than simply 'two wires between the power plant and a house'! So let's stick to the final part of the connection -i.e. between the distribution transformer and a house!In Europe, there are indeed two wires between the distribution transformer and a house. These are called the 'line conductor' (the 'hot' conductor) and the 'neutral conductor'. The neutral conductor is connected to the earth (ground), while the line conductor has a potential of 230 V with respect to the neutral conductor; in simple terms, the current then passes along the line conductor and back along the neutral conductor. All appliances in European houses are rated at 230 V.In North America, there are, in fact, three wires between the distribution transformer and the house. One of these is the earthed (grounded) 'neutral conductor', while the other two are the 'line conductors' (the 'hot' conductors). The potential difference between the two line conductors is 240 V, while the potential difference between either line conductor and the neutral conductor is 120 V. Again, in simple terms, currents pass along the line conductors and back along the neutral conductor. In North America, most appliances are rated at 120 V so are connected between a line conductor and the neutral conductor, but some 'high power' appliances (like stoves, etc.) are rated at 240 V and must be connected between the two line conductors.
Why do power transmission lines not have neutral conductor?
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!
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 situations use copper as a conductor?
Phone lines, power lines, and household cables.
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.
What power lines send electricity over a nationwide network?
Transmission lines
What transmission?
A: It could mean two thing transmission as in broadcast radio TV and so forth or power transmission lines to supply real power to USA states
What are electrical transmission towers for?
Electrical transmission towers are meant to hold the power lines and to carry electricity.
What type of metal is a great conductor of electricity?
Silver is the best conductor of electricity, with copper a close second. Gold is third on the list followed by aluminium. Power distribution systems commonly use copper for underground power lines and aluminium for overhead lines.
