The three-phase asynchronous motor is to rely on access to 380V at the same time the three-phase AC power supply (120 degree phase) of a class of motor power supply, the rotor and the stator rotating magnetic field of three-phase asynchronous motor in the same direction, different speed of rotation, there are slip, so called three-phase asynchronous motor.
When the three-phase motor stator winding into the three-phase alternating current, will produce a rotating magnetic field, the rotating magnetic field cutting rotor windings, thus the induced current in the rotor winding (the rotor winding is closed, the rotor current carrying conductor pathway) under the action of the electromagnetic force in the stator rotating magnetic field, thus forming the electromagnetic torque the rotating shaft of the motor and drive the rotation of the motor and the motor rotation direction and rotation direction of the magnetic field.
When a conductor cuts a magnetic field line in a magnetic field, an induced current is generated in the conductor, and the name of the induction motor is thus derived. The combined action of the induced current and the magnetic field exerts a driving force on the rotor of the motor.
We let the closed coil ABCD rotate around the axis XY in the magnetic field B. If a magnetic field is rotated in a clockwise direction, the closed coil is subjected to a variable magnetic flux to produce an induced electromotive force that generates an induced current (Faraday's law). According to Lenz's law, the direction of the current is: the effect of the induced current always blocks the cause of the induced current. Thus, each conductor bears the Lorentz force F opposite the direction of motion of the induced magnetic field.
A simple method to determine each conductor force F direction is specified by three to the right hand (the thumb in the effect of magnetic field on the current induced magnetic field direction, the direction of the force index. Place the middle finger in the direction of the induced current. In this way, the closed coil is subjected to a certain torque, which rotates along the same direction as the induction magnetic field, which is called a rotating magnetic field. The electric torque generated by the closing of the coil rotates to balance the load torque.