In a synchronous motor it the back e.m.f. generated in the armature at noload is approximately equal to the applied voltage, then
Correct answer: D. the excitation is said to be hundred per cent
- A. the motor is said to be fully loaded
- B. the torque generated is maximum
- C. the excitation is said to be zero per cent
- D. the excitation is said to be hundred per cent
Explanation
With negligible armature impedance drop at no load, an induced back e.m.f. equal to the applied voltage corresponds to 100% excitation, since excitation percentage is approximately Eb/V × 100.
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