Radial Forces in External Rotor Permanent Magnet Synchronous Motors With Non-Overlapping Windings

Induction Motors Versus Permanent-Magnet Actuators for Aerospace Applications

“…The non-overlapping single layer winding was considered the most favorable option due to its underlying advantages of lower copper losses and lower torque ripple [19]. Owing to the non regularly distributed magnetic forces along the air-gap, a unidirectional pulling force that rotates with time and generates noise and vibration in the motor is present under such winding configurations [19]. Radial magnetic forces are computed by Maxwell stress tensor as follows:…”

“…Even though the alternate teeth wound winding is considered a more favorable choice, it presents some serious drawbacks. The number of poles and slots has to be chosen with extreme care, in order to maintain high values for the winding factor and minimize the values of the torque ripple and the rotor losses respectively, which incur a significant increase in machine noise [19]. In order to indentify the favorable winding layout and the numbers of rotor poles and stator slots, different winding topologies have been examined by using the time-stepping FE analysis in conjunction with the optimization procedure.…”

Practical Design Considerations for Large PM Machines

“…To evaluate the danger of different types of short circuit faults, not only currents and voltages should be predicted, but also radial and tangential forces on teeth and pole faces should be calculated [28]- [29]. During short circuit faults, forces will be much greater than normal conditions and the mechanical structure may be destroyed under the reinforced force.…”

Design and Analysis of Permanent Magnet Synchronous Generator Considering Magnetically Coupled Turbine-Rotor System

“…Many researchers have studied the characteristics of rotor vibration for permanent magnet synchronous machines [3][4][5][6][7][8][9]. However, they modeled the assembled rotor system and they did not consider electromagnetic characteristics of permanent magnet machines according to the rotor dynamic results.…”