Electrical Machines 2 Important Questions and Answers

Electrical Machines 2 Important Questions and Answers:

1. What do you mean by single layer and double layer winding?

Answer:

  • Single Layer Winding: It has a slot with one coil side. To get maximum emf coil span should be equal to one pole pitch.
  • Double Layer Winding: It has 2 coil sides per slot, one at bottom and one at top of the winding. Number of stator slots = number of coils.

2. What are the various function of damper winding provided with alternator?

Answer:

Functions of Damper Windings are

  1. It is used to prevent hunting (momentary speed fluctuations). It is used to dampout the oscillation when generator starts hunting.
  2. It is used to suppress the negative sequence field.

3. What is a synchronous capacitor?

Answer:

When the synchronous motor operates on no-load, it acts as a static capacitor and hence under the this condition motor is called as synchronous condenser (or) synchronous capacitor. It is mainly used for power factor correction.