The PM permanent magnet synchronous motor is an innovative development in the field of electric motor technology, which combines the high-precision speed control typical of a synchronous motor with the simple and robust design of an asynchronous squirrel-cage motor. Mechanically, the PM motor is similar to the traditional asynchronous induction motor, but in terms of performance, it can deliver much better results.
The rotors of the PM motors are made of rare earth - permanent magnets that create a constant magnetic field. The rotor rotates at exactly the same speed as the magnetic field generated by the stator winding, regardless of the torque demanded by the shaft.

Due to this synchronous operation, there are no magnetization losses of the rotor, which leads to lower power consumption and less heating of the motor itself.
Synchronization thus improves dynamic performance by providing constant torque over a wide speed range, high efficiency even at low frequencies (efficiency is much higher than that of asynchronous motors) and without the need for forced ventilation.