# Most Important Synchronous Motor MCQs

Synchronous motors are the electrical machines that convert AC electrical power to mechanical power. Electrical Engineering XYZ shares 10 Most Important synchronous motors MCQs.

## Sort The advantages of amortisseur winding

Sort The advantages of amortisseur winding:

1. It increases stability
2. It develops torque which is useful for fast machine
3. It develops torque which is useful for slow machines
4. All of these

Correct answer: 4. All of these

## The correct statement about the speed of synchronous motor

The correct statement about the speed of synchronous motor:

4. It is pulsating and change at irregular intervals

## The synchronous motor is not a self starting motor because

The synchronous motor is not a self starting motor because:

1. It uses damper winding
2. No stator is present
3. The slip is zero in the motor
4. The rotor’s instantaneous torque reverses after half cycle

Correct answer: 4. The rotor’s instantaneous torque reverses after half cycle

## The overexcited synchronous motor is used to

The overexcited synchronous motor is used to:

2. Support loads which have low torque
3. Supply reactive power
4. None of these

Correct answer: 3. Supply reactive power

Explanation: The overexcited synchronous motor provides reactive power to the power system and it can be used for the power factor correction

## The method which can be used to start a synchronous motor

The method which can be used to start a synchronous motor:

1. Use an external prime mover
2. Reduce the stator frequency to safe point
3. Use Amortisseur windings
4. All of these

Correct answer: 4. All of these

## Speed regulation of the Synchronous motor is

Speed regulation of synchronous motor is:

1. 0
2. 1
3. 10
4. 100

## The maximum pullout torque in a synchronous motor occurs at

The maximum pullout torque in a synchronous motor occurs at:

1. 45º
2. 60º
3. 90º

## Synchronous motors are self-starting, the statement is

Synchronous motors are self-starting, the statement is:

1. True
2. False

## The power factor of under excited synchronous motor is

The power factor of under excited synchronous motor is:

2. Lagging
3. Unity
4. Zero

## The percent slip of synchronous motor is

The percent slip of synchronous motor is:

1. 0
2. 0.5
3. 99.5
4. 100