Homopolar motor

A homopolar motor made with a battery cell and a coiled wire.

A homopolar motor is a direct current electric motor with two magnetic poles, the conductors of which always cut unidirectional lines of magnetic flux by rotating a conductor around a fixed axis so that the conductor is at right angles to a static magnetic field. The resulting force being continuous in one direction, the homopolar motor needs no commutator but still requires slip rings.^[1] The name homopolar indicates that the electrical polarity of the conductor and the magnetic field poles do not change (i.e., that it does not require commutation).

^ Lynn, L. (1949). "§197-§204 'Acyclic or Homopolar Machines' in Section 8 - Direct-Current Generators and Motors". In Knowlton, A.E. (ed.). Standard Handbook for Electrical Engineers (8th ed.). McGraw-Hill.

[Knowlton_(1949)-1] Lynn, L. (1949). "§197-§204 'Acyclic or Homopolar Machines' in Section 8 - Direct-Current Generators and Motors". In Knowlton, A.E. (ed.). Standard Handbook for Electrical Engineers (8th ed.). McGraw-Hill.

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