Traditional synchronous motor and permanent magnet synchronous motor
The stator structure of the synchronous motor is the same as the front induction motor. It belongs to the AC motor. Only the stator winding passes through the symmetrical alternating current, which will generate a certain rotational magnetomotive force in the air gap. Unlike an asynchronous motor, its rotor speed is consistent with the rotational speed of the rotating magnetic field.
4 is a conventional electric excitation synchronous motor in which a rotor winding is wound around a salient pole of a rotor and is taken out through a slip ring and a brush on the shaft. That is, its field magnetomotive force is provided by an external DC power. Therefore, its control performance is better, power factor and efficiency can be made higher. However, because of the need for an external exciter, the volume is large, and the brush slip ring needs regular maintenance, so this kind of motor is mostly used in power plant generators, which is relatively rare in automobiles.
The most used in new energy vehicles is the permanent magnet synchronous motor. The difference is that the rotor core has no windings. Only the surface-mounted or built-in permanent magnets are generated by these magnets and generated by the stator. Electromechanical energy conversion occurs by the action of a rotating magnetic field.
Because the car needs frequent speed regulation, the motor's rotational speed is designed to be relatively high, so the permanent magnet synchronous motor with built-in magnetic steel on the right has advantages due to its good mechanical strength, and has a relatively high magnetic force for the motor with built-in magnetic steel. The resistance torque is more conducive to saving the amount of magnetic steel and improving the weak magnetic performance.
