Study on the Selection of the Number of Magnetic Poles and the Slot-Pole Combinations in Fractional Slot PMSM Motor with a High Power Density

Fractional slot, PMSM motors with a properly designed electromagnetic circuit allow for obtaining high power density factors (more than 4 kW per 1 kg of total motor weight). The selection the number magnetic poles to specific dimensions and operating conditions motor, as well slots selected is subject analysis in this article. This issue extremely important because it affects mass value shaft torque, rotor losses. aim work select solutions highest values factor and, at same time, lowest object study fractional slot an external solid core surface permanent magnets (SPM). Motor weight approximately 10 kg, outer diameter 200 mm maximum 50 4800 r/min. article analyzes range from 2p = 12 24 various slot-pole combinations individual poles. target function objective was achieved calculations results were verified on physical model. best 20-pole, 30-slots (highest efficiency loss) 24-pole, 27 density).