What is commutator in DC motor?

A commutator is a rotary electrical switch that periodically reverses the current between the rotor and the external circuit. Commutators are used in DC machines (DC motors and DC generators) universal motors. In a motor, a commutator applies an electric current to the windings.

How does a commutator reverse the current?

Two or more stationary electrical contacts called “brushes” made of a soft conductor like carbon press against the commutator, making sliding contact with successive segments of the commutator as it rotates. Make a sketch of a two segment commutator and you will see that the current direction reverses every half turn.

What is the function of commutator in electric motor?

The function of commutator ring in an electric motor is to reverse the direction of current flowing through the coil every time coil just passes the vertical position during a revolution. Hence as the direction of the current is reversed, the torque is changed in the direction.

How does a commutator switch AC to DC?

In a generator the commutator picks off the current generated in the windings, reversing the direction of the current with each half turn, serving as a mechanical rectifier to convert the alternating current from the windings to unidirectional direct current in the external load circuit.

What is a commutator and how does it convert AC to DC?

Commutator and Brushes All generators produce a sine wave, or AC currents when the rotor turns in the magnetic field. The commutator on the DC generator converts the AC into pulsating DC. The commutator assures that the current from the generator always flows in one direction.

What is AC commutator motor?

In electric motor: Alternating-current commutator motors. A specially designed series-commutator motor may be operated from a single-phase alternating voltage supply. When the supply current reverses, both the magnetic field and the armature current are reversed. Thus, the torque remains in the same direction.

Which direction of DC motor reverses current?

Each half turn of the armature causes the brushes to contact a new split ring, reversing the direction of current flow through the armature windings, which reverses the polarity of the electromagnetism produced in the armature.

What is the purpose of a commutator in a DC motor?

Commutator is simply a mechanical rectifier used to reverse the direction of current every time coil moves through the plane perpendicular to the magnetic field so as to To keep the torque on a DC motor from reversing its direction. For AC motor rectification is not required thus Commutator is not needed rather a slip ring is used.

What is the function of a commutator in a DC generator?

The commutation in DC machine or more specifically commutation in DC generator is the process in which generated alternating current in the armature winding of a dc machine is converted into direct current after going through the commutator and the stationary brushes.

What is the function of commutator in DC machine?

Commutator: In the case of the DC generator, the commutator is used to convert generated AC in armature into DC. In the case of the DC motor, the commutator is used to convert DC to A.C. Due to the limitation of commutator dc generators are not usually designed beyond 650 V

What role does the armature do in a DC motor?

The armature conducts AC even on DC (Direct Current) machines via the commutator (which periodically reverses current direction) or due to electronic commutation, (e.g. in a brushless DC motor). The armature provides housing and support to the armature winding.