Why the air gap between the pole pieces and the armature is kept very small?

Electrical Engineering Electrical Machines
1
  • The air gap between the pole pieces and the armature is kept very small to keep the field strength at its highest value.
  • This is due to the reason the flux lines can pass through iron very easily than the air gap.
  • The small air gap generates high voltage.
  • Larger the air gap means stronger must be the magnetizing force to produce the required voltage hence the air gap is kept very small.