A three-phase motor means that when the three-phase stator windings of the motor (each with a phase difference of 120 degrees), a rotating magnetic field will be generated after the three-phase alternating current is applied, and the rotating magnetic field will cut the rotor winding, thereby generating an induced current in the rotor winding ( The rotor winding is a closed path), and the current-carrying rotor conductor will generate electromagnetic force under the action of the rotating magnetic field of the stator, thereby forming an electromagnetic torque on the motor shaft, driving the motor to rotate, and the direction of rotation of the motor is the same as that of the rotating magnetic field.

  Working principle: When a symmetrical three-phase alternating current is fed into the three-phase stator winding, a rotating magnetic field that rotates clockwise along the inner circle space of the stator and the rotor at a synchronous speed n1 is generated. Since the rotating magnetic field rotates at a speed of n1, the rotor conductor is stationary at the beginning, so the rotor conductor will cut the stator rotating magnetic field to generate an induced electromotive force (the direction of the induced electromotive force is determined by the right-hand rule). Since the two ends of the rotor conductor are short-circuited by the short-circuit ring, under the action of the induced electromotive force, an induced current in the direction of the induced electromotive force will be generated in the rotor conductor, which is basically the same as the direction of the induced electromotive force. The current-carrying conductor of the rotor is subjected to electromagnetic force in the stator magnetic field (the direction of the force is determined by the left-hand rule). The electromagnetic force generates electromagnetic torque on the rotor shaft, driving the rotor to rotate along the direction of the rotating magnetic field.

Through the above analysis, it can be concluded that the working principle of the motor is as follows: when the three-phase stator windings of the motor (each with a phase difference of 120 degrees in electrical angle) are connected to the three-phase symmetrical alternating current, a rotating magnetic field will be generated, and the rotating magnetic field will cut the rotor winding. Induced current is generated in the rotor winding (the rotor winding is a closed path), and the current-carrying rotor conductor will generate electromagnetic force under the action of the rotating magnetic field of the stator, thereby forming an electromagnetic torque on the motor shaft to drive the motor to rotate, and the direction of rotation of the motor is consistent with the rotation The direction of the magnetic field is the same.