TORQUE RIPPLING OF UNIPOLAR MULTI-POLE ELECTRIC MOTOR WITH PERMANENT MAGNETS
Read the full article
The article deals with the physical and mathematical model of inactive three-phase unipolar multi-pole permanent magnet motor; equivalent replacement circuit of magnetic circuit and analytical expressions describing spectral structure of residual torque are received. It has been found that the torque is caused by the presence of harmonics of the air gap magnetic conductivity and their interaction with each other. The residual torque is the alternating function, changing from the rotor rotation angle with the dominant frequency in the sixth harmonic of the angular range pole pitch. It was determined and analytically shown that the angular deviation from the predetermined position of the toothed rotors relatively to each other causes the third harmonic of residual torque changing.