Question

The increased load demand in a synchronous motor is met by:
1. relative shift between stator and rotor poles
2. decrease in stator current
3. increase in speed
4. reduction in speed

Answer 1

Correct Answer - Option 1 : relative shift between stator and rotor poles

• Synchronous motor runs only at synchronous speed (when at steady state) which is related to the supply frequency.
• When the load is increased or decreased, then its speed will momentarily decrease or increase resulting in the adjustment of load angle or torque angle and then the motor comes to its steady-state position.
• Therefore, synchronous motor meets the increased load by the change in its load angle i.e. the relative shift between stator and rotor poles.