Comparison of apparent power consumption in Synchronous Reluctance and Induction Motor under vector control

The advances in power electronics devices have opened the possibility of counting on Synchronous Reluctance Motors (SynRM) where variation of speed is required. However, Induction Motors (IM) have successfully supplied this demand in industrial applications. As for traction applications, SynRM aided by Permanent Magnet is also an alternative to Interior Permanent Magnet Motors (IPM). In this study, a 55kW Inverter-Driven Induction Motor (IDIM) was designed and evaluated through Indirect Field Oriented Current Control (IFOCC) strategy. Likewise, an equivalent Synchronous Reluctance Motor with inductance ratio in the range of 6-10 was also designed by using the same stator as IDIM. A Vector Control (VC) strategy based upon the point of maximum power factor was implemented to test its performance. Both motors optimized for variable speed applications were compared under the same variations of load, voltage and frequency in order to assess their consumption from an input apparent power point of view. By assuming a limit for the input power provided by the same Variable Frequency Driver (VFD), the Induction Motor was able to bear a higher overload, whereas the Synchronous Reluctance Motor compared favorably and showed lower power consumption in average under intermittent loads.