Why do the phases of a motor spin the rotor?

In summary, when a 3 phase motor is energized, a rotating magnetic field is created that interacts with the magnetic field of the rotor, causing it to spin. This is due to the principle of electromagnetic induction, where changing magnetic fields induce a current in a conductor, which in turn creates a force that causes movement. The direction of rotation is dependent on the direction of the current in the phases of the motor.
  • #1
kolleamm
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Assuming we have a 3 phase motor I've always wondered why is it that the rotor spins rather than just being compleltly pulled towards the direction of the phase or the electromagnet? What causes that angular movement?
 
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  • #2
kolleamm said:
Assuming we have a 3 phase motor I've always wondered why is it that the rotor spins rather than just being compleltly pulled towards the direction of the phase or the electromagnet? What causes that angular movement?
Rotating magnetic field
 
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  • #3
This is a question that is best answered with animations. There are many designs of DC motors and AC motors. The video below animates one of them.

 
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FAQ: Why do the phases of a motor spin the rotor?

Why do the phases of a motor spin the rotor?

The phases of a motor, also known as the stator, create a rotating magnetic field that interacts with the permanent magnets on the rotor. This interaction causes the rotor to spin and creates motion in the motor.

How do the phases of a motor create a rotating magnetic field?

The phases of a motor are made up of electromagnets that are powered by electricity. When the electricity flows through the coils of wire, it creates a magnetic field. By alternating the direction of the electricity flow in each phase, a rotating magnetic field is created.

What role do the permanent magnets on the rotor play in the motor?

The permanent magnets on the rotor are crucial for the motor to function. They interact with the rotating magnetic field created by the phases and are repelled or attracted, causing the rotor to spin. Without these magnets, the motor would not be able to generate motion.

Can the phases of a motor be controlled to change the speed of the rotor?

Yes, the speed of the rotor can be controlled by adjusting the frequency and voltage of the electricity supplied to the phases. This changes the strength and direction of the magnetic field, which in turn affects the speed of the rotor.

Why are the phases of a motor arranged in a specific pattern?

The phases of a motor are arranged in a specific pattern to create a balanced magnetic field that ensures smooth and efficient rotation of the rotor. This pattern also allows for precise control of the motor's speed and direction of rotation.

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