Most pumps and fans operating in commercial and industrial applications are driven by AC induction motors. “ACIM”, which means “alternating current induction motor”, is an asynchronous kind of motor that depends on electric current to carefully turn the rotor. Torque is produced by electric current in the rotor. The electric energy is produced 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 means “permanent magnet synchronous motor”, relies on magnets to turn the rotor, which spins at the same rate as the PMSM’s inner permanent magnet synchronous motor rotating magnetic field.

There are a few key differences between AC induction Motors and Permanent Magnet Synchronous Motors.