Elmer Discussion Forum

vencels wrote: ↑12 Feb 2024, 14:25 How do you excite your coils - voltage or current?

My coils are current excited. I haven't tried voltage excitation.

My problem was fixed by switching from 2 to 1. Have you tried using BDF with order 1 for your case?

Sure, it is a bit tricky to visualise, since there's so many lines and no visible difference anymore, but I gave it a shot:

Individual currents (Left: Circuit Components, Right: FEA surface integral): Sum of all currents:

Wow, what a circuit! Do you have some tool for building it? I have used elmer_circuitbuilder to create the circuit. It is fairly straightforward using that. Just requires modifying the circuits.definition file afterwards to put the time varying currents in. Plotting the circuit was done using pydot...

This is a diagram of the circuit:

Hi, I am trying to calculate currents induced in individual conductors in an electric motor (similar to this forum post ). But I am getting a mismatch between the Component currents calculated by the CircuitsAndDynamics solver and the currents I calculate by integrating `current density e` over the ...

Hi, I would like to calculate the AC losses of a motor winding. To do that, I have created a 2-D model with separate conductors in the slot (view Slot_Conductors.png). But I am struggling to enforce the same current in every turn. I have grouped conductors in the same turn into separate bodies and a...

Makes sense, thanks a lot for clearing this up.

Great, thanks.

So for a 2-D simulation the value needs to be scaled by the axial length of the model, right?

Hi,

Hopefully a straightforward question: What unit is the "Eddy current power" calculated by the MagnetoDynamicsCalcFields solver reported in in the log/scalars file? Is it W/kg? W/m^3?

Thanks
Kevin

Hi Peter, I ended up using 24 components since the machine I am modelling has 24 slots. I had a look at how increasing the number of components impacts the core loss (view attachment), and this seems a reasonable value. I used 60 time steps per electrical period. Is there a rule of thumb for how man...