Result interpretation : Text Output

In this part the text outputs of MANATEE are reviewed before using the post processing commands.

The overall text output should look like that:

MANATEE Simulation text output
MANATEE Simulation text output

If one wants to remove all the text outputs in the command line, the parameters Input.Simu.is_com must be set at 0 (in Pre/Post group in the GUI).

Some warnings/info messages may appear, one should carefully read them and check that they do not represent an issue.

In the following text output one can find the results of a theoretical vibroacoustic study:

Theoretical vibroacoustic study
Theoretical vibroacoustic study

This table sweeps the slot/pole interactions force harmonics in open-circuit and identifies potential harmful force harmonics. These harmonics represent both radial and tangential force harmonics. This analysis relies on analytical equations and can be run separately from numerical simulations. It helps interpreting MANATEE numerical results.

The signification of the different variables is detailed in the theoretical vibroacoustic study article. The lower are hr and ks, the higher are the reluctance harmonics magnitude and the higher are vibration and noise at resonance.

In this example, one can see that some resonances occur with the breathing-mode of the stator stack (r=0) at 12-th and 24-th times the electrical frequency due to slot per pole interactions. More especially the (2*5+1)p=11p and (2*6+1)=13p ranks of magnet field interact with the first stator slot harmonic to create a force wave at 12fs of wavenumber 0.

One can also see that the smallest wavenumber is 8 which corresponds to the theoretical value of the Greatest Common Divider between slot and pole numbers GCD(Zs,2p)=GCD(48,8)=8.

Note that this theoretical study does not include higher space harmonic effects, in particular the space harmonics present in the stator winding mmf.

The next text outputs sums up the main parameters of the machine:

Machine main parameters
Machine main parameters

The rotation direction of the main flux is determined based on the winding pattern. To reverse the rotation direction one can permute the phase in the simulation project using Input.Simu.perm_cur=[2,1,3].

In the following outputs one should check the slot fill factor and the weight calculation:

Slot fill factor and machine weight
Slot fill factor and machine weight

The mean turn length depends on the overhang end winding geometry. For random wound winding the effective length of the winding overhang is difficult to estimate, so a tuning factor can be introduced in Input.Geometry.Kwoh. If the slot fill factor is above 100% a wrong slot geometry or winding turn number or wire section might have been used.

Here one can check the discretization is high enough:

Discretization validation
Discretization validation

The vibration model outputs are then summarized:

Vibration model outputs
Vibration model outputs

The acoustic model outputs are summarized:

Acoustic model outputs
Acoustic model outputs

Note that the numerical accuracy of MANATEE acoustic noise calculation is lower than +/-0.3 dB.

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