Torque characteristics of double-stator permanent magnet synchronous machines
Abstract: The torque profile of a double-stator permanent magnet (PM) synchronous machine of 90 mm stator diameter having different rotor pole numbers as well as dual excitation is investigated in this paper. The analysis includes a comparative study of the machine’s torque and power-speed curves, static torque and inductance characteristics, losses and unbalanced magnetic force. The most promising flux-weakening potential is revealed in 13- and 7-rotor pole machines. Moreover, the machines having different rotor/stator (Nr/Ns) pole combinations of the form Nr = Ns ± 1 have balanced and sym-metric static torque waveforms variation with the rotor position in contrast to the ma-chines having Nr = Ns ± 2. Further, the inductance results of the analyzed machines re-veal that the machines with odd rotor pole numbers have better fault-tolerant capability than their even rotor pole equivalents. A prototype of the developed double-stator ma-chine having a 13-pole rotor is manufactured and tested for verification.
eISSN: 2300-2506 ; ISSN: 1427-4221