As the load is applied to a synchronous motor, the motor takes more armature current because
Correct answer: B. the rotor by shifting its phase backward causes motor to take more current
- A. the increased load has to take more current
- B. the rotor by shifting its phase backward causes motor to take more current
- C. the back e.m.f. decreases causing an increase in motor current
- D. the rotor strengthens the rotating field casuing more motor current
Explanation
When load increases, the rotor falls back by a larger load angle relative to the rotating field. This phase shift increases the torque-producing component of armature current, so the motor draws more current.
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