There are
following conditions must be satisfied for production of torque in the DC
machines:
The relative speed between two fields should be zero with respect to stationary observer. Numbers of stator poles is equal to the numbers of rotor poles. If the numbers of stator poles are not equal to the rotor poles, the resultant torque becomes zero.
The numbers
of equalizing rings in the DC Generator are = Numbers of armature conductors /
Numbers of pair of poles
What is
meaning of winding has been developed for 100% equalization connection?
If all the armature conductors are connected to the equalizer rings, it is called as 100% equalization connection.
Θ
(Mechanical) = θ (Electrical) / Pole pairs
= θ (Mechanical) × 2
/ P
Where P = Number of poles
Describe
the function of compensating winding? Where it is located?
Function of
compensating winding
The function of the compensating winding is to neutralize the cross magnetizing effect of the armature reaction. These windings are embedded in the slots of the pole shoes.
Losses in
the DC Generator
Iron loss:
(1) Hysteresis loss and (2) Eddy current loss
Armature
copper loss
Field
copper loss
Mechanical
losses: (1) Friction loss and (2) Windage loss
Which
losses are considered as iron losses?
The hysteresis loss and eddy current loss are considered as iron loss.
Principle
of DC generator
The DC
Generator works on the principle of the dynamically induced emf. Whenever
conductor cuts the flux, dynamically induced emf in it according to the
Faraday’s law of electro – magnetic induction.
What are
the essential conditions for the generation of emf?
The essential conditions for the generation of emf is
