why power generation is done in 3 phase why power generation is not done in 4 phase or 5 phase
after single phase.... three phase is the most successful.... here in three phase u will get 120 degree phase shift both in time domain and space domain which is the neccessery condition to create a r.m.f through which we can get torque.... and one more point is.... in three phase delta connection third hjarmonics will not create any problem..... thats y we stayed with three phase itself...
For3 Phase system the phase angel between transmission line is360/3=120 Degree. As the number of phase increases the phase difference will decrease and more number of times transposition is required. It affects the Installation cost of transmission of Transmission towers.
1)When we derive the expression for power delievery, then only in 3 phase system the reactive components cancelled out and max power is delievered.
2)The efficiency of the system increases with increase in number of phases but also the cost of conductors and complexity to achieve higher phases(more than 3) also increase.
3)We can get 3 phase system by adding just one more conductor to single phase.
4)Only in 3 phase system the power delieverd by all phases are equal.
5)The phases are displaced at equal angle(120 deg) if balanced.
6)Not much difference in delieverd power b/w 3,4,6 or 12 phases.
7)Even number phases are not such desirable as they may cancel out the parameter components, such that we achieve not sufficient power at the recieving side.
8)A 4,5 or more phase transformer is difficult and costly to design.
1 to produce rotational magnatic feild we need at lease tree phase its like shaire we can not make stable shair with one or two stand we need at least3 , sow in electrical enginiring we use three becouse its its the best between choises less phase mean less complication and moore economic
Advantage of 3 phase over 1 phase : In single phase we have to use neutral wire 3 phase wiring is costless compared to 1 phase Higher phases: More than three phases are typically only useful when you need really clean electricity (lesser harmonic effects) or need to interact with very high voltage DC systems. Higher phases can be considered when you need to transfer a large amount of power, but there's the added consideration of integrating the higher number of phases with the three-phase standard for distribution.
Why we cannot use 6 phase supply instead of 3 phase supply? AnswerRequest Follow1 4 ANSWERS Avinash Kumar Avinash Kumar Written Oct 22, 2015 Thanks for A2A. Basically We can use 6 phase and in fact it is being used in certain research laboratories involved in particle physics and stuff. Experiments were done upto 12 phase. For explanation of why 6 phase is limited to special cases and not common in day today life - kindly look at this post Why are there only 3-phase electrical power systems? why not 6-phase, 9-phase, 12-phase, or some other number of phases? 717 Views · View Upvotes · Answer requested by Mohammed Ziya Upvote2 Downvote Share Sai SunilComment...RecommendedAll Robert Harvey Robert Harvey Written Sep 18, 2016 Economics. You can build polyphase systems with as many poles as you like. Some stepper motors use 4phases (of course, they aren't sinusoidal either, but that's another story). Some synchro systems used as compass repeaters on ships etc. use 6, largely for reasons of backwards compatibility with early devices. Polyphase systems are a trick to transfer the rotating magnetic field inside one device (the generator) to another (the motor). The minimum number of wires to do this is 3, and since wires cost money we use the minimum. 2 won't do it, because there is a 180 degree ambiguity in two wires. A single phase induction motor will run equally well in either direction. (Single phase induction motors have some sort of local gadget to make them start, such as a phase shift capacitor, and that chooses one direction. Remove it and start them by flicking and they can go either way)
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