Recent trends indicate the use of permanent magnet (PM) motors because of its energy savings over induction motors. PM motors offer energy savings, higher power densities, and improved control. The upfront cost of a PM motor may be higher than an induction motor, but the total cost of ownership may be lower. However, a PM motor system brings design challenges in terms of selecting the best variable frequency drive (VFD) as well as a filter to protect the motor.
