If in a synchronous motor, driving a given mechanical load and drawing current at a leading power factor from constant voltage supply its field excitation is increased, its power factor
Correct answer: B. will become less
- A. will become more
- B. will become less
- C. will remain unchanged
- D. none of the above.
Explanation
A leading power factor indicates overexcitation; increasing field current makes the current still more leading and increases its phase angle from the voltage. Thus the numerical power factor becomes less, even though the leading nature becomes stronger.
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