What are the methods to reduce the effect of armature reaction?

1) The armature reaction causes the distortion in main field flux. This can be reduced if the reluctance of the path of the cross-magnetizing field is increased. The armature teeth and air gap at pole tips offer reluctance to armature flux. Thus by increasing length of air gap, the armature reaction effect is reduced.

What is used to overcome armature reaction in a generator?

North to south. (3A2-C7-02) A method of overcoming armature reaction is by: Reversing the brushes of the armature conductors.

How is armature reaction corrected?

The effect of armature reaction can be neutralized by use of compensating winding. It is always placed in series with armature winding. The armature ampere conductors under pole shoe must be equal to compensating winding ampere conductors which will compensate armature mmf perfectly.

Which method limits cross Magnetising effect?

Which method needed to limit cross-magnetizing effect? Explanation: By ultimately increasing the reluctance of the magnetic circuit at the pole tips so that the armature reaction effect is neutralized.

How do Interpoles minimize the effects of armature reaction?

Similar to compensating winding, interpoles neutralize the effect of armature conductors mmf by producing a counter mmf in the interpolar region (GNA). The difference is that interpoles nullify the reactance voltage induced in the coil that makes a delay in the reversal of current in the coil undergoing commutation.

How does Interpole reduce armature reaction?

Interpoles are wired in series with the armature. Any changes in the armature current due to armature reactance, loading, or self-inductance pass through the interpole windings. This creates a changing magnetic field equal to and opposite that of the armature, thereby cancelling the effect.

How compensating winding neutralizes the effect of armature field?

In order to neutralize the cross magnetizing effect of armature reaction, a compensating winding is used. Because the compensating windings are wound to produce a field that opposes the magnetic field of the armature, they tend to cancel the cross magnetizing effect of the armature magnetic field.

Which of the following is the most effective method for correction of armature reaction for rapidly fluctuating loads?

For rapidly fluctuating loads, compensating windings are far more effective than interpoles, but in very large machines both methods may be employed.

What is the effect of armature reaction in dc generator?

The adverse effects of armature reaction: Armature reaction weakens the main flux. In case of a dc generator, weakening of the main flux reduces the generated voltage. Armature reaction distorts the main flux, hence the position of M.N.A. gets shifted (M.N.A. is perpendicular to the flux lines of main field flux).

What is armature reaction in dc generator?

3.10 Armature reaction in d.c. generators. Armature reaction is the effect on the main field flux of that flux set up by the currents in the armature winding. 3.7 shows the two main poles of a d.c. generator and the distribution of the magnetic flux which crosses the airgap and enters the armature.

What are the effects of armature reaction?

Armature reaction has two undesirable effects: First, it distorts the main field. Secondly, it reduces the main field flux or both. When the main field is distorted, then there will be a cross magnetizing effect.

What are the methods to change the direction of rotation of motor?

That’s right: Determining the motor’s correct rotation. We all know that the direction of rotation of a 3-phase motor can be changed by reversing two of its stator leads. This interchanging, if you will, reverses the direction of the rotating magnetic field within the motor.