Table of Contents
- 1 Why does speed of synchronous motor remain constant even under variable load?
- 2 How does the synchronous motor maintain its speed?
- 3 What is meant by synchronous speed?
- 4 What is meant by synchronous motor?
- 5 How does excitation control the speed of a synchronous motor?
- 6 What is the relationship between rotor speed and voltage?
Why does speed of synchronous motor remain constant even under variable load?
This is because the load torque demand increases then the torque produced by the motor. Hence motor draws more current to produce more torque to satisfy the load but its speed reduces. In case of synchronous motor speed always remains constant equal to the synchronous speed, irrespective of load condition.
How does the synchronous motor maintain its speed?
In the synchronous AC motor, the speed of rotation is synchronized to the frequency of the AC input current. Also, produced torque can be regulated with the phase difference between them. The torque of a synchronous motor is produced by the phase difference between the rotating magnetic field and the rotor.
Why is synchronous motor speed?
The synchronous speed of an AC motor is determined by the frequency of the source and the number of poles. The reason for this is if the armature turns exactly at synchronous speed, then the magnetic field of the stator windings no longer cuts the rotor windings.
What is meant by synchronous speed?
Definition of synchronous speed : a definite speed for an alternating-current machine that is dependent on the frequency of the supply circuit because the rotating member passes one pair of poles for each alternation of the alternating current.
What is meant by synchronous motor?
Synchronous motor is the motor when rotor speed synchronise with speed of rotating magnetic field. Rotor speed of synchronous motor locked with the speed Rotating magnetic field. So the speed of synchronous motor must be constant and fixed. This speed solely depends upon frequency and no of poles.
What is synchronous speed of a stator?
If this ac power is wired into the stator coils, a rotating magnetic field is established. The rotor can have permanent magnets or windings energized by rectified dc, fed via a brush and slip ring arrangement. The speed of the rotating stator field is called the synchronous speed.
How does excitation control the speed of a synchronous motor?
Synchronous motors with direct current excitation are typically supplied with excitation control equipment to apply the excitation in the correct moment and control the power factor. Once the motor is in operation, the speed of the motor is dependent only on the supply frequency.
What is the relationship between rotor speed and voltage?
The above equation (1) shows that the rotor speed N bears a constant relationship with the field poles and the frequency of the generated voltage in the armature winding. A machine that runs at synchronous speed is called a synchronous machine.