Most pumps and fans operating in commercial and industrial applications are currently driven by AC induction motors. “ACIM”, which stands for “alternating electric permanent magnet synchronous motor current induction motor”, is an asynchronous type of motor that relies on electric current to turn the rotor. Torque is certainly produced by electric current in the rotor. The electric current is generated through electromagnetic induction from the magnetic field of the stator windings. In an 
ACIM, the rotor often rotates at a lesser speed compared to the magnetic field. A “PMSM”, which stands for “permanent magnet synchronous engine”, depends on magnets to carefully turn the rotor, which spins at the same speed as the PMSM’s internal rotating magnetic field.
There are some key differences between AC induction Motors and Permanent Magnet Synchronous Motors.