Rotating magnetic field

**Oscillating magnetic fields.** Sine wave current in each of the three stationary coils produces three sine varying magnetic fields perpendicular to the rotation axis. The three magnetic fields add as vectors to produce a single rotating magnetic field.

**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 is the resultant magnetic field produced by a system of coils symmetrically placed and supplied with polyphase currents.^[1] 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.^[2]

Rotating magnetic fields are often utilized for electromechanical applications, such as induction motors, electric generators and induction regulators.

^ Graham, Frank Duncan (1921). Audels Engineers and Mechanics Guide. New York: THEO. AUDEL & CO. p. 594.
^ Bucher, Elmer E. (January 1919). "Practical wireless instruction". The Wireless Age. 6 (4): 18–19.

[1] Graham, Frank Duncan (1921). Audels Engineers and Mechanics Guide. New York: THEO. AUDEL & CO. p. 594.

[:0-2] Bucher, Elmer E. (January 1919). "Practical wireless instruction". The Wireless Age. 6 (4): 18–19.

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