A DC Motor, or a direct current motor, converts electrical energy into mechanical energy. A DC Motor is one of the basic types of electric motors available on the market. The other type of electric motor is of course the AC Motor, or alternating current motor. Among DC Motors, there are shunt-wound, series-wound, compound-wound and permanent magnet motors.
In a shunt-wound DC Motor, the field coils and the armature are connected in parallel (or shunt) formation. This causes the field current to be proportional to the load on the DC Motor.
In series-wound DC Motors, the field coils and armature are connected in a series and the current flows through the field coils only.

A compound-wound DC Motor is a combination of both a shunt-wound DC Motor and a series-wound DC Motor. A compound-wound DC Motor has features of both these configurations.
All DC Motors are equipped with magnets. These magnets are either permanent magnets or electromagnetic windings. They are responsible for producing a magnetic field. As soon as current passes through the wire or coil (also known as the armature) of the DC Motor which are placed strategically between the north and south poles of the magnet of the DC Motor, the field generated by the armature interacts with the field from the magnet and applies torque. In a DC Motor, the magnet forms the stator. The armature of the DC Motor is placed on the rotor and a commuter subsequently switches the current flow from one coil to the other. The commutator then connects the stationary power source to the armature via the use of brushes or conductive rods. It is interesting to note that DC Motors operate at a fixed speed for a fixed voltage and there is no slip.

The commutator aims to transfer current from a stationary point to the rotating shaft. Brushes, electric contacts on the commutator, are responsible for connecting the power source to the armature. At certain times during the rotation of a DC Motor, the commutator must reverse the current. However, this can lead to decreased DC Motor life because of the wear and tear that occurs through all the friction and arcing.

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