Electric Drives (3160919) MCQs
MCQs of Scalar control or constant V/f control of induction motor
| 41. |
VSI is not suitable for multi-motor drives
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Answer:
Option (b) |
| 42. |
The input voltage of the voltage source inverter remains constant, and their output voltage is independent of the load
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Answer:
Option (a) |
| 43. |
In VSI fed Induction Motor drives the magnitude of the load current depends on the nature of
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Answer:
Option (b) |
| 44. |
The disadvatage of stator voltage control method using 3-Ф ac voltage controller feeding a 3-Ф I.M is/are
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Answer:
Option (d) |
| 45. |
By controlling the _____________ of the thyristors connected in antiparallel in each phase, the rms value of the stator voltage can be regulated
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Answer:
Option (d) |
| 46. |
Speed control of I.M. using stator voltage controller uses
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Answer:
Option (c) |
| 47. |
How many pairs of anti-parallel connected thyristors are required to construct 3-Ф ac voltage controller feeding a 3-Ф I.M. for stator voltage control.
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Answer:
Option (b) |
| 48. |
In a 3-phase voltage source inverter used for speed control of induction motor, antiparallel diodes are used across each switching device. The main purpose of diodes is to:
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Answer:
Option (c) |
| 49. |
V/f is maintained constant in the following case of speed control of induction motor:
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Answer:
Option (b) |
| 50. |
A 50 Hz, 3 phase induction motor with 4 pole stator is supplied by mains, which contains a pronounced fifth time harmonic. The speed of the fifth space harmonic will be
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Answer:
Option (b) |
