Cancellation of stator or rotor mmf

By application of the Howtos article "How to cancel stator or rotor mmf" based on tuto_SCIM_05, in order to cancel all stator field harmonics and keep only rotor field harmonics, one can put (cf : tuto_SCIM_19 project)

Input.Simu.is_mmfs = 0;
Input.Simu.is_mmfr = 1;

In order to keep stator field harmonics only (cf : tuto_SCIM_20 project):

Input.Simu.is_mmfs = 1;
Input.Simu.is_mmfr = 0;

In the GUI, these two parameters are in Magnetics\Assumption.

270. Overall noise level with rotor field harmonics only (left, 19), stator field harmonics only (middle, 20), and all field harmonics (right, 05)
Overall noise level with rotor field harmonics only (left, 19), stator field harmonics only (middle, 20), and all field harmonics (right, 05)

These graphs can be obtained using plot_VS_ASPL_overall. One can notice that in all cases, a significant resonance occurs. This is because this slotting resonance is linked to the fundamental airgap mmf combined with reluctance harmonics: the fundamental airgap mmf has the same time (fs) and space (p) frequency content whatever the case. The interaction of rotor and stator field make the magnitude of this fundamental wave change (depending on the load angle), but not its frequency characteristics.

Depending on the phase angle of each mmf harmonic, the addition of rotor and stator field might increase some vibration and noise harmonics (case of the first resonance at 388 rpm) or decrease them.

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