Permanent Magnet Synchronous Motor Setting Analysis Based on Altair Flux Software

1) Switch from static eccentricity to dynamic eccentricity:

Compared with the geometric center of the rotor for the static eccentric rotation center, the geometric center of the stator for the dynamic eccentric rotation center. In the software, you only need to modify the motion setting of the rotor rotation based on the static eccentric model to a setting method of rotating around the geometric center of the stator. However, since the dynamic eccentric rotor squeezes the air, the air on the stator side needs to be changed to a squeezeable motion method.

2) Start setting the dynamic eccentricity working condition from the .py file imported from FluxMotor:

First, delete the model mesh, enter Sketch and set the offset of the model rotor. The offset setting here is the same as the static eccentric rotor geometric offset. The only difference is that the sliding boundary circle model does not need to be set. (It should be noted that the maximum value of the offset DX and DY may cause model geometric interference problems. Make sure that the sliding boundary circle is large enough to contain the eccentric model)

The steps are the same as establishing the geometric offset parameters DX and DY (refer to the operations in the text), and setting the offsets of the coordinate systems _IM_CART and _IM_POLAR, thus completing all the dynamic eccentricity settings.

However, in the case of dynamic eccentricity, since the central rotation axis of the rotor is at the geometric center of the motor, the simulation of one cycle is a mechanical cycle. It should be noted here when setting the solution, that is, the mechanical angle is 0° to 360°.

Similarly, after the calculation is completed, obtain the rotor dynamic eccentric electromagnetic torque curve by clicking General data > Post processing > Curve > 3D curve (2 I/O parameter) on the left.

Click General data > Post processing > Curve> 2D curve (2 I/O parameter) to obtain the rotor dynamic eccentricity electromagnetic torque curve, and double-click the generated curve to obtain specific rotor torque information.

4 Conclusion

This article mainly introduces the types of motor eccentricity problems, and how to use Flux software to set the settings and eccentricity post-processing process required for the dynamic eccentricity and static eccentricity conditions of permanent magnet synchronous motors. It can be applied to the estimation of motor operating characteristics and related performance under eccentricity fault mode in the early stage of motor design. This article includes the compressible motion mode (implementation path A) in the setting of the dynamic eccentricity mode based on the two-dimensional model of the motor. This is the setting condition required after the geometric center of the rotor air gap is modified based on the static eccentricity model. If the rotating air is appropriately adjusted according to the dynamic eccentricity, the geometric center of the rotating air of the dynamic eccentricity coincides with the geometric center of the stator, and the air motion mode on the stator side can be changed from compressible mode to fixed mode to speed up the calculation speed (implementation path 2).