Question 535Electricity/Electronics - Assistant Engineer70% to pass
What would be the synchronous speed of a 24-pole three-phase synchronous motor operating at 20 Hz?
AI Explanation
The correct answer is B) 100 rpm.
The synchronous speed of a three-phase synchronous motor is determined by the frequency of the supply power and the number of poles in the motor. The formula to calculate the synchronous speed is:
Synchronous speed (rpm) = (120 x Frequency) / Number of poles
In this case, the frequency is 20 Hz and the motor has 24 poles. Plugging these values into the formula:
Synchronous speed (rpm) = (120 x 20) / 24 = 100 rpm
The other answer choices are incorrect because:
A) 50 rpm is too low for a 24-pole motor operating at 20 Hz.
C) 200 rpm is too high for a 24-pole motor operating at 20 Hz.
D) 240 rpm is also too high for a 24-pole motor operating at 20 Hz.
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