In electrical engineering how do 3 phase systems work and operate?

Answer 1

3 live connections with each cycle or phase being 120degrees apart.
This gives a correctlt rotationg magnetic field when used in motors and generators

Answer 2

If you decide to take EE, most of the first year (of four) will be focused on mathematics, physics and probably humanities (universities have this "well rounded" thing often called "freshman inquiry" and "sophomore inquiry.") There will be a smattering of electronics -- perhaps basic digital stuff -- and perhaps a programming class from the CS department. By the time you move into the second year, you will start to see some real electronics going on, along with more mathematics. Physics stops about then, though I think it should NOT stop. I think 2nd year physics is too important. But they can only pack in so much in a year. Bottom line is that I would worry a lot more about your preparation for math and physics, first year out, and a lot less on analog electronics and magnetics. You will get rolling on those things in the following year and it's more important you don't slide, mathematically, at first. That will kill you, if it happens. So focus on math -- particularly calculus, vectors, and operator calculus.

Answer 3

Very basically. The substation supplies, via a three phase transformer, mains voltage to three rows of houses. Each row takes one phase and neutral (single phase UK 240v 50Hz). The neutral, in this case, takes the unbalanced load (current) back to the star point earth. There are many different uses and applications for three phase power/systems. If you want to get a better understanding have a look on the web there are a number of very good articles.
For clarity: if you measure between one phase and neutral you will read (UK) 240v (as in your house). If you measure between phases you will read 415v (240*sqrt3).
Now you're totally confused I'll leave it at that.

Answer 4

power generation and transmission is 3 phase, this is split to single phase for domestic use but 3 phase is more efficient for larger scale use.

UK: the voltage between any two phases is 415v, between phase and neutral is 230v.
a three phase motor can be wired in star or delta, or with star-delta switching.
in star mode the 3 windings of the motor are connected together at the central star point and the phases applied to the outside
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in delta mode the three windings are connected to each other in a triangle format.

star-delta is used with larger motor's as star is best for starting the motor turning, then delta is most efficient for maintaining speed.

Answer 5

The 3 phases are the outputs from 3 seperate coils from the alternator.3 phase generation and transmission is more efficient and economic than single phase.The 3 phases can allign as star or delta connections.Line and phase voltages are different in these connections.In star,line voltage is square root of 3*phase voltage. For more results mail me with your full details..My mail ID is [e-mail]

Answer 6

ina normal house hold you have single phase like your electric dryer which takes 2-110 lines to operate. with 3 phase that is for commercial use you have 3 -110 lines going to a machineeven though you have 3 110 lines in use you actually use less because ther is less of a draw on each line compared to single phase power

Answer 7

total = 415 volts, split them up and join them to common (the outer sheath) and you have 240v, keep the load in balance to spread the heat over all 3 wires. The 240v earth is a true earth. The 415v sheath is the equivalent of neutral.

Answer 8

http://en.wikipedia.org/wiki/3-phase

Answer 9

three phase just means three lives, as used in commercial installations.

Answer 10

You have a hot, a cold, and a ground.