When load on an over-excited or under excited synchronous*motor is increased, rate of change of its armature current as compared with that of power factor is___________?
Correct answer: B. less
- A. more
- B. less
- C. equal
- D. twice
Explanation
With excitation fixed, increasing load changes the armature-current magnitude more gradually than it changes the power factor, so the current's rate of change is taken as less. The exact comparison depends on operating conditions, but option b is the standard machine-theory result.
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