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Alejandro Rodríguez

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Everything posted by Alejandro Rodríguez

  1. Hello Aravind. I think problem there is that you are not in the right application. The options that appear in the solving tag depends on the application you have previously defined. Matlab coupling is working for transient magnetic and transient thermal applications, if you have defined your application as steady state AC or static, Matlab coupling will not be available. Best regards,
  2. Hello Amina, It seems that Simulink is not able to find Flux. To properly run this coupling there are some actions you should do: · You should launch a file to activate the API. The default path to this file is: C:\Program Files\Altair\2019\flux\Flux\Bin\prg\win64\Active_Distributed_Computation_and_API. Please, run this file with administrator rights. · After this, open Matlab/Simulink from Flux Supervisor. Go to Supervisor Options -> Access paths -> Coupled software. There you should put your Matlab directory path. Then open Matlab using the button with an arrow (see image). Please, try this. If your error persists, I will need additional information to solve it. Best regards,
  3. Hello Michael, Unfortunately, Flux is always launched in batch mode. You cannot access to user interface and you must wait to the end of the simulation to have your outputs available. Best regards,
  4. Hi Andoni, I fully agree with you. It is really complicated to obtain accurate values for a given frequency when your losses have been measured at another different frequency, errors as high as 14% can be expected. Actually, we have another remark in the forum about this kind of effects (in this case, the problem was about local spatial effects that may change losses in particular areas of the device, even if the material does not change: Lamination Punching Edges & Packaging: Investigation / Consideration). Unfortunately, I cannot propose you a better alternative. This subject stills a field of study with more questions than answers. Best regards,
  5. Hello Michael, Thank you for your suggestion. We will considerer it as a possible new feature to be included in one of our next releases. Best regards, Alejandro
  6. You are very welcome. If you have any other questions, please do not hesitate to ask them. We are here to help. Have a nice day. Alejandro
  7. Hi Andoni, You are right, if you want to get a simulation as accurate as possible you should use the B(H) curve corresponding with your working frequency. This will affect not only your iron losses but also the global accuracy of your simulation. At the best of my knowledge, it is difficult to estimate B(H) curve at 150 kHz when you only have information for a much lower range. I am sorry but I cannot help with this part. Anyway, the good new is Bertotti model already considers the effect of frequency, as you can see in the formulation of Bertotti’s equation used in Flux: It is worthwhile to notice that Bertotti’s coefficients are taken as frequency independent. This approach usually works well, except when you reach elevate values of frequency. Best regards, Alejandro
  8. Hi Aravind, Please, find attached a tutorial about how to do the coupling between Simulink and Flux. You will also find a Flux project which serves as the starting point of the example. Just some important remarks before you try to run this coupling: · You will find the compatibility of Flux/ Matlab version in the table below. As you can notice, coupling with MATLAB R2019a is not qualified by any Flux version. This does not mean that the coupling is going to fail, but if you want to be sure that you are not going to have any problem with it, it is better to change Matlab version. · Before run Flux – Simulink coupling you should launch a file to activate the API. The default path to this file is: C:\Program Files\Altair\2019\flux\Flux\Bin\prg\win64\Active_Distributed_Computation_and_API Hope this helps. Best regards, Alejandro Rodríguez Flux_simulink_coupling.pdf CABLES.FLU.zip
  9. Hello Raviteja, Sorry for this late answer, but I was thinking about this problem with the coupling and I have a question for you. Have you ever launched the file to activate the API and the parallel computation? It is placed in C:\Program Files\Altair\2019\flux\Flux\Bin\prg\win64\Active_Distributed_Computation_and_API. Launch this code is necessary in order to run any coupling with Matlab or Simulink. Best regards.
  10. Hello Michael, Thank you for your post, you are really talking about an interesting subject. I know well that a fully characterization of BH curves and losses of ferromagnetic materials is not an easy task. Even when we have estimations from manufacturers, the difference between simulations and measures may be high. Unfortunately, Flux material database does not have materials representing non-finally annealed laminations. Anyway, there are several ways to represent this behaviour un Flux, taking advantage of region type “Laminated magnetic non conducting region”. In these regions, you can provide Bertotti’s coefficient in material description or after, in postprocessing. If you know what areas of your machine will be affected by edges and packaging effects, you can define a specific region for them and assign particular Bertotti’s coefficients or BH curves, which may differ from the values uses to describe the rest of your ferromagnetic material. Hope this helps. Best regards, Alejandro Rodríguez
  11. Hello Raviteja, This is probably the problem. Unfortunately, Flux 2019 has compatibility with Matlab versions from 2016b to 2018b, compatibility with 2019b version is not assured, as far as it has not been qualified. Best regards.
  12. Hi, What version of both software are you using? Maybe it is a compatibility problem. Please, find attached the supported Matlab version for different Flux releases. If the problem persists, we will check the environment variables. Best regards.
  13. Hello Raviteja, Actually, this is not a cosimulation error but a license error. It seems that your license is not valable. As you see, problem is not araising when you try to connect to Matlab but before, when it tries to open Flux GUI. I think, best thing you can do is to contact to your local support team, they should be able to provide you a new license file or to fix the one you have already. Best regards.
  14. Hi Zainab, You have a convergence error. Since the numeric method is not converging, reliability of your results (if any) is not guaranteed. Please, check your inputs, your mesh and your simulation time steps, since these are the key factors that can affect convergence. For further helps, additional information about the problem will be needed. In that case, you can post your project in order I can check it. I also advise you to use last software version, i.e., Flux 2019.1. You will enjoy more functionalities that may be useful for your master thesis. Best regards,
  15. You are welcome. Yes, electromagnetic torque is computed for the whole machine. In the same way, any circuit variables (currents, voltages, losses, etc.) are also computed for the whole machine. Best regards.
  16. Hi Andoni, This problem appears because your parallelepiped has a mapped or extruded meshing, which is quite fine, while the infinity box around it has much more rough mesh. A better mesh in the box may help. Anyway, it depends on your specific mesh and the options you have chosen. You can also try to follow one of the two meshing strategies proposed in the document I have sent you. If you want further help you should send me your project, in this way I could propose you more specific solutions. Best regards. Alejandro Rodríguez
  17. Hi Marco, Actually, Flux is going to calculate the iron losses for the machine portion that is represented in the project. In your case, you will obtain the losses for one-half of your machine. Iron losses calculus does not consider automatically any periodicities or symmetries. Best regards, Alejandro Rodríguez
  18. Hello Andoni, This is not an easy topic, depending on the geometry, the meshing process could be quite complex. You will find attached a ".pdf" explaining the meshing process in Flux. I think it will answer most of your questions. “Check mesh” option will verify mesh quality all over the geometry, including relaxation, shadowing and aided mesh. Meshing process also allows to identify bad quality elements, this information may help you to detect poorly meshed areas. Best regards. 4_Mesh-Altair_Flux.pdf
  19. Dear Mandy, Thank you for this suggestion. I will verify Flux documentation and, eventually, update it. Best regards, Alejandro
  20. Dear Mandy, Actually, most of your assumptions are right: the resistance value is calculated by Flux using the equation R=rho*l/A. What it is not right is that, in this case, the value entered in “resistance formula” does not matter. In fact, total resistance associated with stranded coil conductor is the addition of two terms: the one calculated using R=rho*l/A and the value introduced by the user. In other words, value introduced in “resistance formula” field is an additional source of resistance added to the one obtained from geometrical and material properties. In your case, the resistance calculated from geometry is 6 mohm, as can be deduced from your outputs. If evaluated resistance of the non-meshed coils is only 3mohm and not 6 it is maybe due to the existence of symmetries/periodicities or maybe because two coils are associated to the same stranded coil conductor. From a practical point of view: If you only want to take into account the value calculated by Flux from material and geometrical properties (i.e., R=rho*l/(F*A), where F is the fill factor) you should write 0 in “resistance formula” field. On the contrary, if you want to establish yourself the resistance in spite of geometry/material properties, the best way to do so is not to fill the field “material” when defining the non-meshed coil. Best regards, Alejandro
  21. Hello Berke, Please, find attached a pdf which explains clearly the differences between Bertotti and LS methods and how to take advantage of them in Altair Flux. The reason why you cannot use the first two time steps to calculate iron losses is that it uses derivatives and to obtain the derivative in point N you need the variable values in previous points (N-1 and N-2). Best regards, Alejandro Iron_losses-Altair_Flux-Bertotti_LS_models.pdf
  22. Hello Ruud, Actually the problem is that the compiler you are using (MinGW) is not compatible, that is why you are having this issue. This coupling have been tested using Visual Studio 2005 as C compiler. Newer versions of Visual Studio should work fine, also. Please, try again using Visual Studio as compiler. Best regards.
  23. Hello Ruud, I am afraid that, unfortunately, there is no way to control FluxMotor from Matlab. Best regards,
  24. Hello Xiaodong, You are welcome. Yes, you can use this topic to share your project (if you do not have confidentiality issues) or you can send a mail to your local support account. Best regards,
  25. Hello Mandy, I understand your method to calculate cogging torque but I think it is rather difficult to applicate, since it implies to numerically calculate stored energy (not always an easy task) and them derivate it, which is also a tricky process from a numerical point of view. In other words, to assure the accuracy of your results you will need a really dense mesh (especially in the areas where a high quantity of magnetic energy is expected to be stored) and a small time step to be sure that your derivatives have enough precision. These two factor may lead the simulation time to skyrocket. Actually, seeing your results it seems that you need both, a denser mesh and smaller time step. I am not an expert about torque components separation, but I can suggest you to check this paper, it may help you in your research. [2014 Chen] X. Chen, J. Wang et al., “Reluctance torque evaluation for interior permanent magnet machines using frozen permeability”, 7th IET International Conference on Power Electronics, Machines and Drives, PEMD 2014. (https://ieeexplore.ieee.org/document/6836779 ) Hope this helps. Best regards,
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