Synchronous motors questions with answers
99 multiple-choice questions. Open any question for its answer and explanation.
- When the field of a synchronous motor is under-excited, the power factor will be
- The mechanical displacement of the rotor with respect to the stator, in polyphase multipolar synchronous motors running at full load, is of the order of
- In a synchronous motor, the magnitude of stator back e.m.f. Eb depends on
- If load (or torque) angle of a 4-pole synchronous motor is 6° electrical, its value in mechanical degrees is
- Which of the following losses, in a synchronous motor, does not vary with load?
- Armature of a synchronous machine is
- A synchronous motor which works on a leading power factor and does not drive a mechanical load is called as
- Mostly, synchronous motors are of
- The standard full-load power factor ratings for synchronous motors are
- The back e.m.f. of a synchronous motor depends on
- The armature current of the synchronous motor
- Synchronsizingpower of a synchronous machine is
- For V-curves for a synchronous motor the graph is drawn between
- The torque angle, in a synchronous motor, is the angle between
- A synchronous motor is running with normal excitation. When the load is increased, the armature current drawn by it increases because
- In case one phase of a three-phase synchronous motor is short-circuited the motor will
- If in a synchronous motor, driving mechanical load and drawing current at lagging power factor from constant voltage supply, its field excitation is increased, then its power factor
- In a synchronous motor, the damping winding is generally used to
- The maximum power developed in a synchronous motor will depend on
- A synchronous motor connected to infinite bus-bars has at constant full load, 100% excitation and unity power factor. On changing the excitation only, the armature current will have
- Which of the following motors will be used in electric clocks ?
- Under which of the following conditions hunting of synchronous motor is likely to occur ?
- If the field circuit of an unloaded salientpole synchronous motor gets suddenly open-circuited, then
- A pony motor is basically a
- A synchronous motor can be used as a synchronous capacitor when it is