The basic working principle of permanent magnet synchronous motor
The principle of permanent magnet synchronous motor is as follows.
Three-phase current is passed into the stator winding of the motor. After the current is passed in, a rotating magnetic field will be formed in the stator winding of the motor. Since the permanent magnet is installed on the rotor, the magnetic pole of the permanent magnet is Fixed, according to the principle that the magnetic poles of the same sex attract opposites and repel each other, the rotating magnetic field generated in the stator will drive the rotor to rotate, and finally the rotational speed of the rotor is equal to the rotational speed of the rotating magnetic poles generated in the stator, so the permanent magnet can be The starting process of a synchronous motor is considered to be composed of an asynchronous starting stage and a pulling-in synchronous stage. In the research stage of asynchronous start, the speed of the motor gradually increases from zero.
The main reason for the appeal is that it is caused by a series of factors such as asynchronous torque, permanent magnet generator braking torque, etc. , so the speed is oscillating up during this process. During the starting process, the motor is accelerated by this torque, and most of the other torques are mainly based on braking properties. When the speed of the motor increases from zero to the rotating speed of the magnetic field close to the stator, the speed of the permanent magnet synchronous motor may exceed the synchronous speed under the influence of the pulse torque of the permanent magnet, and the overshoot of the speed occurs. But after a period of rotational speed oscillation, it is finally pulled into synchronization under the action of synchronous torque.