News

What is the working principle of the rotor and stator of a three-phase motor?

Updated:2023-09-14
Summary:The rotor and stator are two essential components of a three-phase motor, and they work together to ...
The rotor and stator are two essential components of a three-phase motor, and they work together to convert electrical energy into mechanical motion. Here's an overview of the working principle of the rotor and stator in a three-phase motor:
Stator:
The stator is the stationary part of the motor, and it consists of a core made of laminated iron sheets and insulated copper windings.
Three sets of windings, corresponding to the three phases of the AC power supply (typically labeled as A, B, and C), are wound around the stator's core.
When three-phase AC voltage is applied to these windings, it generates alternating magnetic fields within the stator. The key to the stator's operation is that the magnetic fields in the windings are 120 degrees out of phase with each other, creating a rotating magnetic field.
The rotating magnetic field's direction changes as the AC voltage alternates between phases, resulting in a magnetic field that appears to "rotate" within the stator.

Rotor:
The rotor is the rotating part of the motor and is located inside the stator.
In an induction (asynchronous) three-phase motor, the rotor consists of a series of conductive bars or a cage made of conductive materials, typically aluminum or copper.
When the stator's rotating magnetic field is established, it induces a current in the rotor due to the principle of electromagnetic induction. This induced current creates its own magnetic field.
The interaction between the rotating magnetic field of the stator and the magnetic field induced in the rotor generates a torque. This torque causes the rotor to start rotating, following the rotating magnetic field produced by the stator.
The rotor will rotate at a slightly slower speed than the stator's magnetic field, a difference known as "slip." The slip allows the motor to produce torque, which is necessary for driving mechanical loads.
The stator generates a rotating magnetic field when three-phase AC voltage is applied to its windings. The rotor, located within the stator, responds to this rotating magnetic field through electromagnetic induction, creating its own magnetic field. The interaction between the stator's magnetic field and the rotor's magnetic field generates torque, which causes the rotor to rotate and drives the mechanical load connected to the motor's shaft. This is the basic working principle of a three-phase motor.

Recommended Products

Cotact Us