Correct option is A
When over-excited at no load, a synchronous motor acts as a capacitor. This is because it begins to take a leading current at no load. A synchronous motor in this state is known as a synchronous condenser.
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An over excited synchronous motor at no load acts as:
Similar Questions
- 1)
A 4-pole star connected; three phase alternator has 6 slots per pole per phase in the stator. What is its slot angle in degree?
- 2)
What is a Synchronous condenser?
- 3)
At what speed, a 4-pole alternator has to be driven, so as to generate a voltage at a frequency of 25 Hz? frequency of 25 Hz?
- 4)
Which of the following statements are INCORRECT about auxiliary motor starting in synchronous motors?
A) The function of the auxiliary motor is to run the synchronous motor at a speed less than its synchronous speed.
B) The rating of the auxiliary motor is much lower than that of the synchronous motor.
C) This method is used only for loaded synchronous motors.
D) Auxiliary motor starting is not a commonly used starting method in modern days. - 5)
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B)The Eddy current loss is reduced by laminating the core.
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D)Core losses increase with the square of the load. - 6)
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- 7)
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- 8)
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- 9)
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