Constructional Features of Rotating Electrical Machines – 2

Which type of slots are used in the construction of large size and small size induction motors respectively?

Large synchronous machines are constructed with armature winding on the stator because stationary armature winding
(i) can be insulated satisfactorily for higher voltages
(ii) can be cooled more efficiently
(iii) would lead to reduced slip ring losses
(iv) would have no slot harmonics
(v) would have reduced armature reactance
Which of the above statements are correct ?

The stator frame and end covers in synchronous and induction machines are designed to ___________

What is the equation for frequency of generated EMF?

What are the advantages of providing the field winding on rotor and armature winding on the stator?

In which of the following applications, wound rotor type of induction motor is used?

For an induction motor,
(i) squirrel cage type is simpler and more economical in construction
(ii) wound rotor type requires less maintenance
(iii) squirrel cage type is more rugged and requires less maintenance
(iv) no external resistance can be inserted in the rotor circuit of squirrel cage induction motor
(v) no external resistance can be inserted in the rotor circuit of a wound rotor induction motor
Which of the above statements are correct?

In a synchronous machine, salient pole construction has been found to suit best for ________

How many poles should the alternators driven by the oil engines and hydraulic turbine prime movers must have, for better operation?

What is the advantage of connecting two coils in parallel?