Single-speed voltage-driven full-load sinusoidal vibro-acoustic simulation with permeance / mmf model

A new project is set-up in tuto_test_SCIM_05 by copy/paste tuto_test_SCIM01 (or by loading it with the GUI).
The following parameters are modified for 2% slip operation at same speed:

Input.Simu.N0 = 60*60*(1-2/100)/3;
Input.Simu.slip = 2/100;
Input.Simu.is_mmfr = 1;

In the GUI, N0 ans slip are in the Worflow group and is_mmfr is in Magnetics/Assumption.

The efficiency is now 90.7%, and the torque reaches positive values (261 Nm):

>> run_MANATEE('tuto_test_SCIM_05')
>> Output.Electrical.Cout

The rotor mmf can now be displayed with plot_rmmf_space

130. Rotor mmf
Rotor mmf

One can notice the rotor slotting harmonics at Zr-p=25 and Zr+p=31.

No additional resonance occurs (plot_VS_ASPL_overall)

130. A-weighted sound pressure level spectrum
A-weighted sound pressure level spectrum

The overall SWL is higher due to higher phase current, but the rotor mmf does not bring additional significant force harmonics.
The variable speed ideal sonogram (assuming constant slip through all speed range) is given by plot_VS_ASPL_spectrogram

130. A-weigthed sound presure level sonagram
A-weigthed sound presure level sonagram

This sonagram confirm that there is no new force harmonic due to rotor field. One can notice that some spectral leakage is introduced due to slip. This does not affect the acoustic noise at resonance, but one can reduce it by increasing the number of revolutions. For instance with Input.Simu.Nrev = 4; one obtains the new following sonogram:

sonagram with Nrev = 4
sonagram with Nrev = 4

The maximum SPL is unchanged but the frequency resolution has been increased. The rest of the spectra can be completed by defining a lower nominal speed for the single speed simulation as discussed above.

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