Learning Forum

[Purity]

Hi,

I designed a symmetrical PM machine but the average torque value I got is lower that the expected value. I indicated the symmetry multiplier value in design setting window, please do I need to mulitply the average torque value with the symmetry multiplier value? If I do not have to muliply it, what could have resulted to low torque vaue?

Thanks

[H.Shirzad2]

If you are using Matching ( master/slave ) boundary conditions, then on project manager, you have to click right click on Model and select symmetry multiplier.

[Purity]

Hi,

Thank you for your reply. I have already selected the symmetry multiplier, but the average torque value is about one-quarter of my expected value. Please, what can be the cause?

Thank you.

[MirandaH]

Are you using quater size model? Do you have boundary condition setup? Is the depth of the model correct if you are using Maxwell 2D?

[Purity]

Thank you for responding.

I am using quarter size 2D model and I have set up the master and slave boundary and also the vectorpotential boundary. I used the stack length as the depth of the model. I am suprise that I am getting almost one-quarter value of my expected average torque even after adding the symmetry multipler of 4.

Thank you.

[MirandaH]

Different torque value could be caused by operating speed between simulation and your test, excitation if the initial position and the current phase is aligned to provide correct torque. material propertity if magnet magnetization direction is correct. 

[Purity]

I used the same operating speed. 

I used the postion where the phase A induced voltage is at maximum and the phase A flux linkage is zero at zero coil excitation. It gave me the highest torque ever produced.

Please let me know how to optimize the magnetization of seven magnets regarding their positions and directions, rather than choosing positions on the magnets directly.

Thank you

[Purity]

I have identified the problem which was from the modal depth.

Thank you.