Fault analysis

Mostafa Ahmadi
Mostafa Ahmadi Altair Community Member
edited September 2021 in Community Q&A

Hi

I have simulated my model using the current source and get the right answer compare to my reference. I need to use voltage source to model my motor and get the current for fault analysis (eccentricity/short circuit faults). 

When I used voltage source, I can't get the expected results and the current is extremely high. 

What is the solution to solve it?

 

 

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Answers

  • Alejandro Rodríguez
    Alejandro Rodríguez
    Altair Employee
    edited September 2021

    Hello,

    This problem may have very different causes. Perhaps your voltage  rms value is wrong or, more probably, the phase angle between the voltage source and the rotor position is not the right one (in the case of synchronous machines). Both causes may lead to great increment in the currents through your machine.

    Another potential cause is a bad estimation in winding resistance or in the end-winding inductance. Anyway, in order to better answer your question more information about your machine topology and the type of study you are carrying out will be needed.

    Best regards.

  • Mostafa Ahmadi
    Mostafa Ahmadi Altair Community Member
    edited November 2018

    I used Flux for all my simulations (the version is 2018). I run the simulation using current source, and after that calculated the voltage of the current source. I used the voltage in a voltage source and I expected that I get the value of my previous simulation with current source but the difference was very high. 
     

    Let me ask you something general related to my problem. How can I model eccentricity/short circuit faults using Flux and get the current for motor Current signal analysis? I know that maybe my question is very general and it may not be a good question. 

  • Mostafa Ahmadi
    Mostafa Ahmadi Altair Community Member
    edited December 2018

    To explain the work, I want to model the short circuit on SynRM and PM-assisted SynRM machines. For each study, I need current to do signal analysis. I am aware that a proper way might be the co-simulation with MATLAB. However, as you know it would take a very long time to get the results with desired accuracy. 

     

    A friend of mine has simulated SynRM machine using voltage source and gotten good results compared with experimental test. He used imposed speed and set the internal and external characteristic of the mechanical set. Is it correct to use the way my friend used for PM-assisted SynRM too?

     

    Unfortunately, I do not know how to set these numbers. I was wondering if you could give a reference for it. In addition, I have doubt whether this method is working for my study.

     

    Can you tell me whether there is any other way to do these studies?

     

    Thank you so much in advance to read my questions and for your help. 

  • Mostafa Ahmadi
    Mostafa Ahmadi Altair Community Member
    edited December 2018

    i would be thankful if someone from Altair or other users help me. 

  • SimonGuicheteau
    SimonGuicheteau
    Altair Employee
    edited September 2021

    This thread is quite old but I'm adding a comment here

    If you use the same voltage with the correct shift compared to the current source, you should obtain very similar results after a few periods. The main difference is that current source will give you the steady state straight away in the first period but i may take ~10 periods to get to the steady state with the voltage source.