EE6504 ELECTRICAL MACHINES-II, Third year, Department of Electrical & Electronics Engineering, First and second Units Questions.

PART A(10*2=20)

1. Why a 3-phase synchronous motor will always run at synchronous speed?
2. What are the advantages of salient pole type of construction use for synchronous
machines?
3. Why are alternators rated in kVA and not in kW?
4. Define distribution factor.
5.What is meant by load angle of an alternator?
6Define the term voltage regulation of alternator
7.What does hunting of synchronous motor mean?
8.What is synchronous condenser?
9.Write the applications of synchronous motor.
10.What is synchronizing?
PART B (16*5=80)
11.With a neat sketch, explain the construction and working principle of alternator. (16)
12.(i).What is armature reaction ? Explain briefly about armature reaction.(8)
      (ii).Derive an emf equation of an alternator. (8)
13.State and explain parallel operation of alternators.(16)
14.(i).Explain V and inverted V  curves as applied to synchronous motor.(6)
      (ii). Describe the different methods of starting of synchronous motor.(10)
15.(i).Draw and explain  the phasor diagram  of a synchronous motor operating at lagging and leading      
power factor.(10)
      (ii). Give the principle of operation of synchronus motor. (6)