What happens to the rotor of a 3 phase induction motor?

In this type of three phase induction motor the rotor is wound for the same number of poles as that of the stator, but it has less number of slots and has fewer turns per phase of a heavier conductor. The rotor also carries star or delta winding similar to that of the stator winding.

How do change in supply voltage and frequency affect the performance of a 3 phase induction motor?

HV decreases both pf and slip but increases torque. Low voltage does just the opposite. Increase in frequency increases pf but decreases the torque . decreases in frequency decreases pf but increases torque leaving percent slip unaffected as before.

What is the relation between stator MMF and rotor MMF?

2. What is the relation between rotor mmf and stator mmf? Explanation: First the stator mmf is calculated. Then it is multiplied by 0.85 to obtain the rotor mmf.

What causes movement in a 3 phase induction motor?

As the magnetic field of the stator rotates, due to the effect of the three-phase AC power supply, the induced magnetic field of the rotor is attracted and will follow the rotation. The rotor is connected to the motor shaft, so the shaft rotates and drives the connection load.

How is the rotor current of a three-phase induction motor and slip of the motor related?

This difference in speed depends upon load on the motor. The difference between the synchronous speed Ns of the rotating stator field and the actual rotor speed N is called slip in a three-phase induction motor. When the rotor is stationary (i.e., N = 0), slip, s = 1 or 100 \%.

What happens to the rotor of a three-phase induction motor if its speed attends to synchronous speed?

If the rotor run at synchronous speed then there will be no difference between the synchronous speed and rotor speed, so the Slip will be zero, hence no torque will be developed and the rotor will slow down. 2.

How does frequency affect current?

As frequency increases, current tends to flow along the surface of a conductor. This is called ‘the skin effect’. The higher the frequency, the more pronounced this effect.

How does voltage affect frequency?

As the voltage increases so does the power out of the area and frequency then increases. This oscillation of power, voltage and frequency can last for several seconds. During this time frequency response will start to act to recover the frequency.

What is the formula for MMF for air gap?

According to the formula (3), the total value of MMF of the magnetic circuit is FΣ1=430+2·36+2·51+180+3,9=788 А. The saturation coefficient of the magnetic circuit is the ratio of the total MMF of the magnetic circuit FΣ to the total value of MMF of the magnetic circuit in the air gap Fδ.

What is the relation between pole pitch and the magnetizing reactance?

What is the relation between pole pitch and the magnetizing reactance? Clarification: The magnetizing reactance is one of the parameters in the leakage reactance calculation. The magnetizing reactance is directly proportional to the pole pitch.

How does the rotor of an AC induction motor receive current?

As the coils are energized, the magnetic field they produce between them induces an electric current in the rotor. This current produces its own magnetic field that tries to oppose the thing that caused it (the magnetic field from the outer coils). The interaction between the two fields causes the rotor to turn.

How is the rotor field of an induction motor produced?

The rotating magnetic field is produced by the three-phase current of the stator in the actual three-phase induction motor. It can be replaced by permanent magnets in a permanent magnet synchronous motor. The three-phase windings of the inner stator are spaced 120° electrical degrees apart.