Armature

Definition

The armature is the rotating part of an electric generator or motor that carries the windings in which the electric current is induced. It is a crucial component that converts electrical energy into mechanical energy or vice versa, depending on the device's function.

5 Must Know Facts For Your Next Test

1. The armature of an electric generator is responsible for converting the mechanical energy of rotation into electrical energy through electromagnetic induction.
2. In an electric motor, the armature converts the electrical energy supplied to it into mechanical energy, causing the motor to rotate.
3. The design and construction of the armature, including the number of windings and the materials used, significantly affect the performance and efficiency of the generator or motor.
4. The interaction between the magnetic field produced by the stator and the current-carrying windings of the armature is what generates the torque that drives the rotation of the machine.
5. The commutator in the armature plays a crucial role in ensuring the correct flow of current in the windings, enabling the production of direct current in generators and the reversal of current direction in motors.

Review Questions

• Explain the role of the armature in the operation of an electric generator.
  • The armature in an electric generator is responsible for converting the mechanical energy of rotation into electrical energy through the process of electromagnetic induction. As the armature rotates within the magnetic field produced by the stator, the changing magnetic flux induces an electromotive force (emf) in the windings of the armature. This induced emf is the source of the electrical energy generated by the machine.
• Describe how the interaction between the armature and the stator in an electric motor produces torque and causes the motor to rotate.
  • In an electric motor, the armature carries the windings that carry the electric current. When this current-carrying armature is placed in the magnetic field produced by the stator, the interaction between the magnetic field and the current in the windings generates a force that produces a torque. This torque causes the armature to rotate, converting the electrical energy supplied to the motor into mechanical energy.
• Discuss the role of the commutator in the armature of an electric generator or motor and how it contributes to the production of direct current or the reversal of current direction.
  • The commutator is a crucial component of the armature in both electric generators and motors. In a generator, the commutator ensures that the induced emf in the armature windings is rectified, producing a direct current output. In a motor, the commutator reverses the direction of the current in the armature windings as the motor rotates, enabling the continuous production of torque and the rotation of the motor.

Related terms

Stator:

The stationary part of an electric generator or motor that provides the magnetic field for the armature to interact with.

Commutator:

A device that reverses the direction of the electric current in the armature windings of a generator or motor, allowing the production of direct current.

Electromagnetic Induction:

The process by which a changing magnetic field induces an electromotive force (emf) in a conductor, which is the fundamental principle behind the operation of generators and motors.