Construction details of synchronous generator

Construction details of synchronous generator

    Consists of two parts namely stator and rotor

Stator

•   Laminated core with slots to hold the armature conductors.
• Laminated construction keeps eddy current losses to be minimum
•   Made up of material like silicon steel to reduce hysteresis losses

Rotor

     Two types

1.       Salient pole type
2.       Non salient pole type

Salient pole type

Non-salient pole or Smooth cylindrical rotor

Difference between salient and cylindrical rotor

SI.NO	Salient pole type	Smooth Cylindrical type
1	Poles are projected out from surface	Poles are not projected
2	Large diameter, small axial length	Small diameter, large axial length
3	Air gap is non-uniform	Air gap is uniform
4	Mechanically weak	Robust
5	Preferred for low speed alternators	Preferred for high speed alternators
6	Prime movers used are water turbines, IC engines	Prime movers used are steam turbines, electric motors
7	Damper winding is provided	Damper winding is not necessary
8	For same size rating is smaller than cylindrical type	For same size rating is higher than salient pole type