Evaluation of demagnetization

Mostafa Ahmadi

 

Hi, 

I have a question on evaluation demagnetization using Altair Flux. 

There are some guide in the software and I have read all of them including: 

1- software help part entitled 'How to use “Evaluation of the demagnetization” in Flux?' 

2- in 'Altair\2019\flux\Extensions\Macros\Macros_Flux2D_Physics\RunDemagnetization2D.PFM' 

3- a video on YouTube 'https://www.youtube.com/watch?v=D_wk_Mvpa5U '

different methods have been explained in these references, and they are not clear at least for me.

 

In the first method, it is mentioned that the nonlinear properties of the magnet should be inserted,  the second one, both linear and nonlinear can be considered, and in the third way, there is another denitrification. What are the differences between these methods (1 and 2)?

First of all, I would like to know which graph you mean by nonlinear (the red one as shown in the following picture), if yes can you explain why and how flux calculate the working points? and if the green one is the correct, a the (Bi, Hi) of this line should be considered as a nonlinear?

How can see the effect of demagnetization on the machine performance (torque, magnet loss, ...)? Does the flux use the nonlinear model for PM loss calculation or the PM loss should be calculated by inserting resistivity of the PM?

Would you please explain about this more or provide any help which I can use for my work.  

How can I used the third approach? When I use the PM properties, I have faced error related to the value of 'transversal relative permeability'. As I asked before, Mr. Abdessamed said that it was like air and I could use '1', but I couldn't use this number in my model. I would be really thankful if you could explain more about this. 

 

Thank you so much in advance for time and consideration. 

 

Kindest regards, 

 

 

 

 

 

 

 

 

 

 

 

Farid zidat_20516

 

Hello Mostafa, 

I suggest you to use the last version of Flux, you can create a non linear magnet and then chose to take or not the demagnetisation during solving.

Mostafa Ahmadi

Dear Mr. Zidat, 

Thank you so much for the shared document, it was really useful. 

Is it possible to plot the demagnetization cure of the defined material as shown in the help file?

Demagnetization model plotted in the help file

 

Demagnetization model plotted in the software environment 

<?xml version="1.0" encoding="UTF-8"?>

 

asoualmi

 

Hi,

Yes, you can draw this curve in Flux. You need to create two sensors:

• Sensor to draw the curve of B

• Sensor to draw the curve of H

Once the project is solved, you draw both curves in the same curve and you select Sensor function of the sensor H.

 

Best regards.

Mostafa Ahmadi

 

Hello Mr. Abdessamed, 

Thank you so much for your explanation. I have faced a warning which does not allow me to solve the scenario. 

   checkPhysic executed
The computation of Js is not possible with these input values.
Please check the values that define the B(H) model.

 

The magnet properties were inserted in FluxMotor>materials part as I attached the screen of magnetic properties tab. 

 

 

 

I also attached the simulation file too. Would you please explain how to cope with this condition. 

 

Thank you so much in advance. 

 

 

 

 

 

 

 

 

asoualmi

Hi,

I checked the Flux project that you send us. When I draw the curve B(H) of the magnet PM_1 I get zero (you can do by selecting the  material PM_1, right click, select    new B(H) curve.Do you have the cure B(H) of the magnet, if it is the case can share it?

Best regards.

Mostafa Ahmadi

Hi, 

Yes, I have the material characteristics. I put the ... of both PM_1 and PM_2. 

I have tried to plot the characteristics of PM_2 using the flux file you sent me, the obtained result was not correct. I think there is problem in the parameters I considered for the materials.

 

 

 

 

 

Mostafa Ahmadi

Is there a way to check the input using analytical calculation?

Mostafa Ahmadi

Altair Forum User said:

Hi,

I checked the Flux project that you send us. When I draw the curve B(H) of the magnet PM_1 I get zero (you can do by selecting the  material PM_1, right click, select    new B(H) curve.Do you have the cure B(H) of the magnet, if it is the case can share it?

Best regards.

Hi 

I provided the characteristics of the materials. Would you please check it and explain why the material is not correct?

 

thank you in advance 

asoualmi

Hi,

I checked the proprieties of the materials using the Flux project that I send before, but I get a wrong B(H) curve of the magnet.

About the Flux project that you send me, the problem come form the material (magnets). I tried another material (I import it form Flux), I reached to solve the project.

Best regards.

Mostafa Ahmadi

Altair Forum User said:

Hi,

I checked the proprieties of the materials using the Flux project that I send before, but I get a wrong B(H) curve of the magnet.

About the Flux project that you send me, the problem come form the material (magnets). I tried another material (I import it form Flux), I reached to solve the project.

Best regards.

Hi Mr. Abdessamed,

Thank you for your reply and checking the model I sent you. 

I was wondering if you could help me to use my material properties.

I have used the material properties reported in the tutorial Mr. Zidat sent me. The B(H) was okay and also there was no error. 

I tried to use the same procedure for the new PM materials which I shared the BH curves. For PM_1 there was an error which said 'The computation of Js is not possible with these input values. Please check the values that define the B(H) model'. For the PM_2, there was no error but when I tried to get the B(H) using your model, I got the wrong B(H). 

I would be really thankful if you could give me any suggestion to overcome these problems. 

 

Kind regards, 

Mostafa