Design of AC Machines (2170909) MCQs

MCQs of Design of Three Phase Induction Motor

Showing 61 to 70 out of 97 Questions
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61.

Mostly the Slip-ring rotor has _____________ winding.  

(a)

Δ connected 3-Φ winding
(b)

rotor bare with end rings
(c)

Y connected 3-Φ winding
(d)

Any of these
Answer:

Option (c)

62.

What is the advantage of the slip ring rotor?

(a)

High starting torque
(b)

power recovery is possible during breaking
(c)

Speed control from rotor side 
(d)

All of these 
Answer:

Option (d)

63.

In the design of a wound rotor three-phase induction motor. Which of the following is the limiting factor while defining the rotor numbers of turns?

(a)

numbers of rotor slot
(b)

rotor frequency
(c)

rotor impedance
(d)

Maximum Rotor voltage between Slip rings
Answer:

Option (d)

64.

In Which condition the Rotor voltage between Slip rings is maximum?

(a)

S=0 (Synchronous Speed)
(b)

S=1 (Stand Still)
(c)

0 < S < 1 (Running)
(d)

All of these
Answer:

Option (b)

65.

What should be the voltage limit for the Rotor voltage between Slip rings of Small and Medium-size IM?

(a)

250 - 500
(b)

500
(c)

1000
(d)

1000 - 2000
Answer:

Option (b)

66.

What should be the voltage limit for the Rotor voltage between Slip rings of High Voltage Large rating &  IM?

(a)

250 - 500
(b)

500
(c)

1000
(d)

1000 - 2000
Answer:

Option (d)

67.

In the design of a wound rotor three-phase induction motor. What are the advantages of keeping the Rotor voltage between Slip rings within the limit?

(a)

It becomes easy & cheaper to insulate Rotor winding.
(b)

it protects a person working on the motor.
(c)

It becomes easy & cheaper to insulate Rotor winding & it protects a person working on the motor.
(d)

Need Brush gear protection & High Current in rotor winding
Answer:

Option (c)

68.

In the design of a wound rotor three-phase induction motor. The number of turns on rotor winding can be calculated by assuming proper 

(a)

numbers of rotor slot
(b)

voltage between the slip rings
(c)

rotor current
(d)

All of these
Answer:

Option (b)

69.

In the design of a wound rotor three-phase induction motor. Rotor Current per Phase Ir = 

(a)

1.15 * [(Is*Ts)/Tr]
(b)

0.85 * [(Is*Tr)/Ts]
(c)

1.15 * [(Is*Tr)/Ts]
(d)

0.85 * [(Is*Ts)/Tr]
Answer:

Option (d)

70.

In the design of a wound rotor three-phase induction motor. The cross-section area of the rotor conductor can be found out by assuming a proper 

(a)

rotor current per phase
(b)

numbers of rotor slot
(c)

numbers of rotor turns per phase
(d)

current density
Answer:

Option (d)

Showing 61 to 70 out of 97 Questions
4 5 6 7 8 9