Editing Rotating magnetic field (section)

{{Short description|Resultant magnetic field}}[[Image:3phase-rmf-noadd-60f-airopt.gif|320px|thumb|'''Oscillating magnetic fields.''' Sine wave current in each of the three stationary coils produces three sinusoidally varying magnetic fields perpendicular to the rotation axis. The three magnetic fields add as vectors to produce a single rotating magnetic field.]][[Image:RMFpatent.PNG|320px|thumb|right|'''U.S. Patent 381968''': Mode and plan of operating electric motors by progressive shifting; Field Magnet; Armature; Electrical conversion; Economical; Transmission of energy; Simple construction; Easier construction; Rotating magnetic field principles.]]A '''rotating magnetic field (RMF)''' is the resultant [[magnetic field]] produced by a system of [[Electromagnetic coil|coils]] symmetrically placed and supplied with [[Polyphase system|polyphase currents]].<ref>{{Cite book|last=Graham|first=Frank Duncan|url=https://archive.org/details/audelsengineers01unkngoog|title=Audels Engineers and Mechanics Guide|publisher=THEO. AUDEL & CO.|year=1921|isbn=|location=New York|page=594}}</ref> A rotating magnetic field can be produced by a poly-phase (two or more phases) current or by a single phase current provided that, in the latter case, two field windings are supplied and are so designed that the two resulting magnetic fields generated thereby are out of phase.<ref name=":0">{{Cite journal|last=Bucher|first=Elmer E.|url=https://archive.org/details/WirelessAgeVols0607/page/n173/mode/2up|title=Practical wireless instruction|journal=The Wireless Age|date=January 1919|number=4|volume=6|pages=18–19}}</ref>

Rotating magnetic fields are often utilized for [[Electromechanics|electromechanical]] applications, such as [[induction motor]]s, [[electric generator]]s and [[induction regulator]]s.