Editing Three-phase electric power (section)

== Generation and distribution ==
{{See also|Mains electricity by country}}

[[File:3-phase flow.gif|thumb|357px|Animation of three-phase current]]

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| footer = Left image: elementary six-wire three-phase alternator with each phase using a separate pair of transmission wires.<ref>''[[Hawkins Electrical Guide]]'', Theo. Audel and Co., 2nd ed., 1917, vol. 4, Ch. 46: Alternating Currents, p. 1026, fig. 1260.</ref> Right image: elementary three-wire three-phase alternator showing how the phases can share only three wires.<ref>''[[Hawkins Electrical Guide]]'', Theo. Audel and Co., 2nd ed., 1917, vol. 4, Ch. 46: Alternating Currents, p. 1026, fig. 1261.</ref>
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At the [[power station]], an [[electrical generator]] converts mechanical power into a set of three [[Alternating current|AC]] [[electric current]]s, one from each coil (or winding) of the generator. The windings are arranged such that the currents are at the same frequency but with the peaks and troughs of their [[wave]] forms offset to provide three complementary currents with a phase separation of one-third cycle ([[Sine wave|120° or {{frac|2π|3}} radians]]). The [[utility frequency|generator frequency]] is typically 50 or 60 [[Hertz|Hz]], depending on the country.

At the power station, transformers change the voltage from generators to a level suitable for [[Electric power transmission|transmission]] in order to minimize losses.

After further voltage conversions in the transmission network, the voltage is finally transformed to the standard utilization before power is supplied to customers.

Most automotive alternators generate three-phase AC and rectify it to DC with a [[diode bridge]].<ref>{{Cite web|url=http://www.rle.mit.edu/per/ConferencePapers/cpConvergence00p583.pdf|title=A New Design for Automotive Alternators|date=August 30, 2017|archive-url=https://web.archive.org/web/20170830033252/http://www.rle.mit.edu/per/ConferencePapers/cpConvergence00p583.pdf|archive-date=2017-08-30}}</ref>