Trial Fixed Outer Rotor Three-Phase Squirrel-Cage Induction Motor and its Basic Characteristics

For a long time, many three-phase squirrel-cage induction motors (IMs) have been used as a flagship and as power sources. Recently, because regulation of the efficiency of IMs was set, the characteristics of IMs have been further studied. However, the squirrel-cage rotor current has not been experimentally studied in detail. The reason is that the squirrel-cage winding (rotor) rotates; thus, measuring the rotor-bar current is difficult. Therefore, we made a trial IM where the construction is an outer rotor IM but the outer rotor is fixed and the stator rotates [hereinafter referred to as fixed outer rotor IM (FOR-IM)]. In this paper, FOR-IM is introduced, and its basic characteristics are presented.