DC motors have been used in industrial applications for years. Coupled with a DC drive, DC motors provide very precise control DC motors can be used with conveyors, elevators, extruders, marine applications, material handling, paper, plastics, rubber, steel, and textile applications to name a few.
Standard DC motors are readily available in one of two main forms:
Wound-field,where the magnetic flux in the motor is controlled by the current flowing in a field or excitation winding, usually located on the stator.
Permanent magnet, where the magnetic flux in the motor is created by permanent magnets which have a curved face to create a constant air-gap to the conven-tional armature, located on the rotor. These are commonly used at powers up to approximately 3 kW.
Torque in a DC motor is produced by the product of the magnetic field created by the field winding or magnets and the current flowing in the armature winding. The action of a mechanical commutator switches the armature current from one winding to another to maintain the relative position of the current to the field, thereby producing torque independent of rotor position.
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