Regulation of the efficiency of electric motors worldwide has recently been tightened further because the contribution of electric motors to overall energy consumption cannot be denied. For many years, induction motors
have fulfilled tasks in various fields of industry; however, alternative motors have also been gaining attention to realize more cost-effective motors over the long term. It is foreseen that induction motors (IMs) may not be
replace-able in single-speed applications, excluding a few special applications; however, applications for which the variation of speed is required offers opportunities for the entry of other motor technologies. Synchronous
reluctance motors (SynRMs) are one option that could provide such benefits. This paper provides the experimental results of SynRMs which, under the rated condition, aim to satisfy the IE4 efficiency class. Five Syn-
RMs ranging in power through 5.5, 15, 37, 75 to 132 kW have been manufactured and tested for experimental comparison with IMs of equivalent output power.