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A polyphase system is a means of transmitting ac power and it has N live wires with the currents phased by 360/N degrees between them. This arrangement when N is 3 or more needs no neutral wire because the return current for each one of the N wires flows back along all the other live wires.
The world-wide standard for electric power transmission uses N=3 and is called 3-phase. Power transmission needs 3 wires when the the three currents are balanced (equal) and 4 wires in other cases where the load currents might not be equal, in which case current flows in the neutral fourth wire.
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∙ 10y ago
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∙ 12y agoA three-phase transformer is a mutual transformer having three identical primary windings and three identical secondary windings, with a pair of primary/secondary windings wound around each of three limbs of a silicon-steel core.
There are various ways in which the primary windings are then connected together and the way in which the secondary windings are connected together, but the most common are in wye (star) or delta (mesh). Each primary winding represents a primary phase, and each secondary winding represents a secondary phase.
If connected in wye, there are (usually) three external line conductors and one neutral conductor. If connected in delta, there are three line conductors.
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∙ 12y agotransformer is static device witch transform electrical energy from primary winding to secondary winding with out change in frequency
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∙ 13y agoPolyphase Transformers are transformers that typically have a three-legged core that can produce at least three different voltages.
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∙ 10y agoA transformer with a three-phase circuit on primary and secondary, in universal use throughout the world in electrical power distribution systems.
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∙ 10y ago3 phase
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What is the current of 1MVA transformer?
This depends on the voltage, and whether it is a three phase or single phase transformer.
Would you install three-phase transformer or bank of three single phase transformer in a large power station and justify by comparing the two schemes?
A three-phase transformer bank is often used in power stations because it is easier to construct and transport very large single-phase transformers, compared with constructing and transforming an equivalent-capacity three-phase transformer.
Can 3 single phase transformers can replace 1 three phase transformer?
Yes, you can use three single phase transformers on three phase applications and interconnect them to serve as a single transformer or you could use one single phase transformer fed from two of the three lines in a step down application.
What will happen if apply two phase supply to a three phase transformer?
A three phase transformer is simply three transformers so, supplying one phase to a set of three transformers will result in only one phase output. Any loads connected to that transformer that are expecting three phase power will malfunction, and could fail.AnswerA three-phase transformer is NOT 'three separate single-phase transformers', as suggested in the original answer. It is a single transformer with three primary and secondary phase-windings wound around a common three-limb ('core') or five-limb ('shell') core. If a single-phase supply was applied to one of the three primary windings, then single phase voltages would appear across each of the three secondary windings and the remaining two primary windings. These voltages would not be out of phase with each other.
Why would you use a three phase transformer in place of a single phase transformer?
the necesscity of two three phase transformers operating in parallel are as follows...if the one transformer fails to give supply,then another transformer can be used in parallel and hance,continuity of supply can be maintained.one transformer can be easily take out from the supply for repair & maintanance.if the load on the substation increases beyond the rated values of transformer, then another transformer can be used to share rhe load of the substation.
What is the current of 1MVA transformer?
This depends on the voltage, and whether it is a three phase or single phase transformer.
What is this system called with three single phase transformer?
Your question is rather vague. If you are asking what do you call a group of single-phase transformers, connected to supply three phase, then the answer is a 'three-phase transformer bank'.
Would you install three-phase transformer or bank of three single phase transformer in a large power station and justify by comparing the two schemes?
A three-phase transformer bank is often used in power stations because it is easier to construct and transport very large single-phase transformers, compared with constructing and transforming an equivalent-capacity three-phase transformer.
Is there a basic difference between a three phase power transformer and a three phase distribution transformer?
The basic difference is the secondary voltages. On a distribution transformer the secondary voltage is very high. This is to overcome line loss for transmission of electricity over long distances. A three phase power transformer is used at the consumers three phase services end to manipulate voltages that consumers need to operate their equipment. The transformer that feeds your house is considered to be a single phase power transformer.
Is there a neutral on a three phase transformer?
It depends on whether you are wye or delta connected. A transformer is a transformer, and a three phase transformer is simply three transformers. The key is in how you hook them up.AnswerIt depends on how the transformer is connected. If one set of windings is connected in star (or wye), then the star point is/canbe earthed and becomes the neutral for that particular connection; this is the standard connection for the secondary (low-voltage) of European distribution transformers. In North American three-phase distribution transformers, the secondary windings are connected in delta, and one phase is centre tapped, earthed, and that becomes the neutral point for a 240/120-V split-phase supply to a residence.This answer applies to both three-phase transformers, and to single-phase transformers which have been connected to form a three-phase transformer bank. (It is incorrect to say that a three-phase transformer is simply three single-phase transformers!)
Can 3 single phase transformers can replace 1 three phase transformer?
Yes, you can use three single phase transformers on three phase applications and interconnect them to serve as a single transformer or you could use one single phase transformer fed from two of the three lines in a step down application.
What will happen if apply two phase supply to a three phase transformer?
A three phase transformer is simply three transformers so, supplying one phase to a set of three transformers will result in only one phase output. Any loads connected to that transformer that are expecting three phase power will malfunction, and could fail.AnswerA three-phase transformer is NOT 'three separate single-phase transformers', as suggested in the original answer. It is a single transformer with three primary and secondary phase-windings wound around a common three-limb ('core') or five-limb ('shell') core. If a single-phase supply was applied to one of the three primary windings, then single phase voltages would appear across each of the three secondary windings and the remaining two primary windings. These voltages would not be out of phase with each other.
Where are three phase transformer systems used?
Any where that a three phase supply distribution is needed to operate three phase equipment.
Why would you use a three phase transformer in place of a single phase transformer?
the necesscity of two three phase transformers operating in parallel are as follows...if the one transformer fails to give supply,then another transformer can be used in parallel and hance,continuity of supply can be maintained.one transformer can be easily take out from the supply for repair & maintanance.if the load on the substation increases beyond the rated values of transformer, then another transformer can be used to share rhe load of the substation.
How do you design a transformer with three phase 400v input and single phase 2000v output?
By design are you going to wind the transformer yourself? In your design you need a 5:1 ratio. On the output side of the transformer any two legs of a three phase transformer is considered single phase voltage. Good luck on your project.
What is the three phase transformer?
it has three primary windings & three secondary windings.
Why vector group is required?
There are various ways in which you can connect a three-phase transformer's primary and secondary windings, or in which you can connect three single-phase transformers to create a three-phase transformer bank. For example: wye-wye, wye-delta, delta-delta, delta-wye, etc.For each connection, there is a natural phase shift between the primary and secondary line voltages. This is called the angular displacement (or 'phase displacement') of the transformer connection.If you wish to parallel two three-phase transformers, or two three-phase transformer banks, then their angular displacements must be the same (there are also other requirements not relevant to this answer).A vector group is a method of specifying a three-phase transformer (or transformer bank) method of connection and its angular displacement. Transformer connections from the same group can be paralleled. Those in different groups cannot
