# What is commutator in AC motor?

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A commutator is a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit. … In a motor the commutator applies electric current to the windings.

## How does an AC commutator work?

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.

## What is the use of commutator?

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.

## Does AC have a commutator?

AC machine doesn’t need a commutator. A commutator is a mechanical rectifier which converts ac to dc and vice versa. It has two major functions is a dc machine: Keep the armature mmf stationary.

## Why do AC motors need brushes?

The field induces a current flow into the shorted armature whose magnetic field opposes that of the field coils. Speed can be controlled by rotating the brushes with respect to the field axis. This motor has superior commutation below synchronous speed, inferior commutation above synchronous speed.

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## Do all AC motors have brushes?

AC induction motors have no brushes and have a much longer life expectancy. DC motor speed is controlled by varying the armature current, while AC motor speed control is achieved by varying the frequency of the alternating current, often with a variable frequency drive(VFD).

## How does commutator reverse current?

The split ring commutator reverse the current in the armature every half revolution when the commutator changes contact from one brush to another. This reverse in current causes the forces acting on the coil to be reversed.

## What is the difference between armature and commutator?

An armature is a combination of the winding, commutator, brushes, and ball bearings.

What is Commutator?

Armature Commutator
It sends alternating current to segments The alternating current is converted to direct by using the segments

## Can commutator convert AC to DC?

Commutator converts the Alternating to direct current in a DC generator. The alternating current generated in the armature windings of the generator gets converted to direct current after it passes through the commutator and the brushes.

## Is commutator present in AC generator?

No commutator is present in AC Generator. To make the current flow in one direction only, DC Generator comprises the commutator.