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Synchronous motor running at the constant synchronous speed. Therefore there is no speed loss, so the speed regulation of synchronous motor is zero.

## What is the maximum speed of synchronous motor?

The 3600 rpm corresponds to **60 revolutions per second**. A similar 2-pole permanent magnet synchronous motor will also rotate at 3600 rpm. A lower speed motor may be constructed by adding more pole pairs. A 4-pole motor would rotate at 1800 rpm, a 12-pole motor at 600 rpm.

## What factors determine the speed of a synchronous motor?

**The frequency of the power supply and the number of poles of the machine** determine the synchronous speed. A synchronous motor is one in which the rotor turns at the same speed as the rotating magnetic field in the stator.

## Why the speed regulation of a synchronous motor is always zero?

Synchronous motor running at the constant synchronous speed. **Therefore there is no speed loss**, so the speed regulation of synchronous motor is zero.

## What are the advantages of synchronous motor?

The advantages of the synchronous motor are **the ease with which the power factor can be controlled and the constant rotational speed of the machine**, irrespective of the applied load. Synchronous motors, however, are generally more expensive and a d.c. supply is a necessary feature of the rotor excitation.

## What is the difference between synchronous speed and actual speed?

The synchronous speed of an AC motor is determined by the frequency of the source and the number of poles. The RPM is calculated by multiplying the frequency times 60 and dividing by the number of pairs of poles. Actual speed of **the induction motor will be less** than the synchronous speed. …

## Are synchronous motors AC or DC?

In a synchronous motor, **AC** power is supplied to the stator to generate a rotating magnetic field. DC power is supplied to the rotor which results in discrete North (N) and South (S) poles.

## What is relation between synchronous speed and frequency?

The synchronous speed of the motor **remains constant if the number of poles and the frequency are constant**.

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Synchronous speed Formula.

No. of Poles | Frequency (50 Hz) | Frequency(60 Hz) |
---|---|---|

2 | 3000 | 3600 |

4 | 1500 | 1800 |

6 | 1000 | 1200 |

8 | 750 | 900 |