What is a Permanent Magnet Synchronous Motor (PMSM)?

Definition:
A permanent magnet synchronous motor is a type of synchronous motor that uses permanent magnets as the rotor excitation source. It generates torque through the interaction between the rotating magnetic field generated by the stator windings and the magnetic field generated by the permanent magnet rotor, thus making the motor rotate.

Working principle：

• Synchronous operation: The rotor speed of the PMSM is the same as the synchronous speed of the rotating magnetic field generated by the stator windings, that is, there is no slip between the rotor and the rotating magnetic field.

• Magnetic field and torque: The rotating magnetic field generated after the stator windings are energized interacts with the magnetic field of the permanent magnet rotor to generate electromagnetic torque and drive the motor to rotate.

• Control method: Accurately control the stator current through methods such as vector control (Field-Oriented Control, FOC) to achieve precise control of the motor speed and torque.

Structural characteristics：

• Permanent magnet rotor: The rotor is equipped with permanent magnets, usually made of neodymium iron boron (NdFeB) material, which has high magnetic energy product and high coercivity.

• Stator structure: The stator windings are arranged in the stator slots and usually adopt three-phase windings to form a three-phase symmetrical magnetic field.

• Brushless design: PMSM usually adopts brushless design and is controlled by an electronic commutator (inverter), which reduces mechanical wear and improves reliability.