What is the effect of number of poles on speed of induction motor?
Table of Contents
- 1 What is the effect of number of poles on speed of induction motor?
- 2 How does the pole number of a synchronous machine affect speed and or frequency?
- 3 How can we increase the speed of synchronous induction motor?
- 4 What will happen if induction motor speed reaches synchronous speed?
- 5 What is the relation between frequency speed and number of poles?
- 6 What is the relationship between speed frequency and the number of poles in a three phase induction motor?
What is the effect of number of poles on speed of induction motor?
The main thing to understand is that increasing the number of poles reduces the motor’s synchronous speed. A 2 pole motor on 60 hz power has a synchronous speed of 3,600 rpm. For an induction motor, that will typically drop by a “slip” percentage, typically about 4\% to 3,450 rpm.
How does the pole number of a synchronous machine affect speed and or frequency?
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….Synchronous Speed.
| Number of Poles | Synchronous Speed NS in r.p.m |
|---|---|
| 12 | 500 |
What are the factors which affecting the speed of the synchronous motor?
The speed of a synchronous motor is dependent on the frequency of the power source and the number of poles the stator has. RPM increases directly with frequency and inversely as the number of poles. The same formula used to calculate the speed of the induction motor is used to determine the speed of this type of motor.
How can we increase the speed of synchronous induction motor?
Synchronous Speed
- V / f control or frequency control.
- Changing the number of stator poles.
- Controlling supply voltage.
- Adding rheostat in the stator circuit.
What will happen if induction motor speed reaches synchronous speed?
Slip. Slip is strongly associated with synchronous speed. If the motor turned at the same RPM as the magnetic field, there would be no relative motion between the rotor and the field. Therefore, no current would be induced into the rotor, and no magnetic field would be created to cause it to turn.
What will happen with the increase in speed of a DC motor?
Explanation: In case of DC motor, the speed is proportional to the back emf (Ea ∝ N). So, with the increase in speed, the back emf also increases. Therefore, armature current is also decreased, in case of series motor, armature current is equal to the line or load current.
What is the relation between frequency speed and number of poles?
If a two-pole alternator creates one cycle of voltage in one second (or one hertz of frequency), a four pole alternator will create two cycles of voltage in one second (or two hertz). The frequency of an alternator is directly proportional to the number of poles in the alternator.
What is the relationship between speed frequency and the number of poles in a three phase induction motor?
What are the relationships among speed, frequency, and the number of poles in a three-phase induction motor? – Quora. The synchronous speed (rpm) equals 60 times the frequency divided by the number of pole pairs. For 50Hz, a two-pole motor will have a synchronous speed of 3000 rpm, a four-pole motor of 1500 rpm.