University Questions with Answers (Long Answered Questions)

University Questions with Answers (Long Answered Questions)

(Regulation 2008)

Dec.-10

Q. 1 Discuss the different power stages of a 3 phase induction motor with losses with the help of a power flow diagram. (Section 5.17)    [8]

Q. 2 Write a note on double squirrel cage motor and explain its equivalent circuit. (Section 5.22) [6]

Q. 3 Write a brief note on induction generator. (Section 5.23)          [8]

May-11

Q. 4 Explain how a three phase supply produces a rotating magnetic field of constant value at constant speed with vector diagrams. (Section 5.2)       [8]

Q. 5 Describe the principle of operation of a 3 phase induction motor with a neat sketch. Explain why a rotor is forced to rotate in the direction of rotating magnetic field. (Section 5.5)          [8]

Q. 6 Derive the torque equation for a three phase induction motor. (Section 5.9) [8]

Q.7 Derive the condition for the maximum torque in a three phase induction motors. Also obtain the expression for the maximum torque. (Section 5.10)        [8]

Q. 8 Prove that to increase the starting torque an extra resistance must be added in the rotor circuit. (Section 5.14)     [6]

Dec.-ll

Q. 9 Describe the principle of operation of a 3 phase induction motor with a neat sketch. Explain why a rotor is forced to rotate in the direction of rotating magnetic field. (Section 5.5)          [8]

Q. 10 Draw and explain a typical torque-speed characteristics for a 3 phase induction motor. Explain the relation between torque and slip before and after the maximum toruque. Show the stable region in the graph. (Section 5.11,   [8]

Q. 11 Develop an equivalent circuit of a 3 phase induction motor. What do the various paramenters represent ? Represent the approximate equivalent circuit and state its significance. (Section 5.18)      [8]

May-12

Q. 12 Describe the constructional features of squirrel cage and slip ring induction motors. Discuss the merits of one over other. (Section 5.4)        [8]

Q. 13 Starting from the equivalent circuit, derive the various power equations of an induction motor. (Section 5.18)     [8]

Dec.-12

Q. 14 Describe the constructional features of squirrel cage and slip ring induction motors. Discuss the merits of one over other. (Section 5.4)        [8]

Q. 15 Describe the principle of operation of a 3 phase induction motor with a neat sketch. Explain why a rotor is forced to rotate in the direction of rotating magnetic field. (Section 5.5)          [8]

Q. 16 Draw and explain a typical torque-speed characteristics for a 3 phase induction motor. Explain the relation between torque and slip before and after the maximum toruque. Show the stable region in the graph. (Section 5.11,   [8]

Q. 17 Develop an equivalent circuit of a 3 phase induction motor. What do the various paramenters represent 1 Represent the approximate equivalent circuit and state its significance. (Section 5.18)      [8]

May-13

Q. 18 Draw and explain a typical torque-speed characteristics for a 3 phase induction motor. Explain the relation between torque and slip before and after the maximum toruque. Show the stable region in the graph. (Section 5.11,   [8]

Q. 19 Show how a 3 phase induction motor can be represented by an approximate equivalent circuit. (Section 5.18) [8]

Q. 20 Explain with necessary diagrams the principle of operation and characteristics of the double cage induction motor. (Section 5.22,        [8]

Dec.-13

Q. 21 Describe the constructional features of squirrel cage and slip ring induction motors. Discuss the merits of one over other. (Section 5.4)        [8]

Q. 22 Describe the principle of operation of a 3 phase induction motor with a neat sketch. Explain why a rotor is forced to rotate in the direction of rotating magnetic field. (Section 5.5)          [8]

Q.23 Derive the condition for the maximum torque in a three phase induction motors. Also obtain the expression for the maximum torque. (Section 5.10)        [8]

May-14

Q. 24 Draw and explain a typical torque-speed characteristics for a 3 phase induction motor. Explain the relation between torque and slip before and after the maximum toruque. Show the stable region in the graph. (Section 5.11,   [8]

Dec.-14

Q. 25 Describe the principle of operation of a 3 phase induction motor with a neat sketch. Explain why a rotor is forced to rotate in the direction of rotating magnetic field. (Section 5.5)          [8]

Q. 26 Draw and explain a typical torque-speed characteristics for a 3 phase induction motor. Explain the relation between torque and slip before and after the maximum torque. Show the stable region in the graph. (Section 5.11,   [8]

Q. 27 Describe the principle of operation of synchronous induction motor. (Section 5.24)    [8]

(Regulation 2013)

Dec.-15

Q. 28 Sketch and explain the torque slip characteristics of the 3-phase cage and slip-ring induction motors. Show the stable region in the graph. (Section 5.11, [16]

Q. 29 Explain the working principle of 3 phase induction motor. (Section 5.5, [8]

May-16

Q. 30 Derive the expression for torque, slip and draw speed-torque characteristics of 3-phase induction motor. (Sections 5.9 and 5.11)   [8]

Q. 31 Explain in detail the equivalent circuit of 3-phase induction motor. (Sections 5.18)     [8]

Dec.-16

Q. 32 Develop the approximate equivalent circuit of a 3 phase induction motor. (Section 5.18)          [8]

Q. 33 Draw and explain the torque-slip characteristics of a 3 phase induction motor. (Section 5.11) [8]

Q. 34 Explain the operation of induction machine as a generator with neat diagram. (Section 5.23) [8]

Q. 35 Explain the speed torque characteristics of double cage induction motor with a neat diagram. (Section 5.22.2)        [8]

May-17

Q. 36 Sketch and explain the torque slip characteristics of the 3 phase cage and slip-ring induction motor. Show the stable region in the graph. (Refer section 5.11) [8]

Dec.-17

Q. 37 Describe the working principle of a 3-phase induction motor. (Refer section 5.5)        [7]

Q. 38 Derive the expression for torque under running condition of a 3-phase induction motor and obtain the condition for maximum torque. (Refer sections 5.9 and 5.10)      [8]

Q. 39 Write short notes on 'Induction generators'. (Refer section 5.23)     [5]

May-18

Q. 40 Explain the construction and working of three phase induction motor. (Refer section 5.4 and 5.5)      [13]

Q. 41 Develop an equivalent circuit for three phase induction motor. State the difference between exact and approximate equivalent circuit. (Refer section 5.18) [13]