Deemed University 2009 A.M.I.E.T.E Electronics

(i) obtain the excitation emf neglecting saliency and assuming Xs=Xd.
(ii) obtain the excitation emf accounting for saliency. (8)

Q.4 a. Derive the exact equivalent circuit of a 3-phase induction motor. What is the difference ranging from the exact and approximate equivalent circuits? From the approximate equivalent circuit, obtain the (i) rotor output, (ii) output power and (iii) output torque. (8)

b. discuss double field revolving theory as applied to single phase induction motor. Mention few applications of single phase induction motor. (8)


Q.5 a. discuss the construction, working and applications of a stepper motor. (8)

b. discuss the working of AC tachometer. Also mention its applications. (8)

Q.6 a. Draw the typical layout of Hydro station and discuss the function of every component. (8)

b. Write notes on (i) Gas turbine and (ii) Diesel generators. (8)

Q.7 a. What is meant by a circuit breaking? explain various methods of interrupting the arc current in circuit breakers. (8)

b. What is relay? provide a classification of relay. elaborate the main features of a good protective relay? (8)

Q.8 a. What is solar energy? How solar energy may be utilized for generation of electrical power? explain with the help of a neat sketch. (8)

b. What is the principle of HVDC transmission? provide the application of HVDC. explain the advantages and operational issues of HVDC transmission. (8)

Q.9 Write short tech. notes on following:

(i) Accumulators
(ii) Switched reluctance motor
(iii) Industrial drives
(iv) Button cells (4 four = 16)

Earning:   Approval pending.