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December 6, 2012 10:17am UTC in response to Mohammadreza Barzegaran

Re: sinusoidal voltage to time dependent solver

Hello,

The Magnetic and Electric fields physics does not support Time-dependent studies, only Stationary and Frequency. You can see it in the Time Dependent step (the yellow sign near the physics's name in the table).

Depending on what you want to do, you need to use another physics, for example Electric Currents.
Note that your model as it is now cannot be solved with a Magnetic interface since it does not respect current conservation (current is "created" on one boundary and "destroyed" on another).

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Andrea Ferrario
Electromagnetics Group
COMSOL AB

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December 6, 2012 4:30pm UTC in response to Mohammadreza Barzegaran

Re: sinusoidal voltage to time dependent solver

Hi

there is in the doc if you get to the right page ;), but you should also check the solver proposed when you enter the physics, there you see which are "set-up" by default, and also by looking to the equations , if you have d/dt 's your time response will work if you have w omega's, the frequency response too, but if none appear, when you switch your selected solvers then no luck.

Also ACDC is assuming instantaneous time response on the magnet fields, else you are in wave propagation mode = RF

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Good luck
Ivar

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December 6, 2012 8:40pm UTC in response to Mohammadreza Barzegaran

Re: sinusoidal voltage to time dependent solver

Hi

check www.comsol.eu/community/forums/general/thread/33429/#p91817 and see if that can inspire you ;)

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Good luck
Ivar

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December 7, 2012 4:55pm UTC in response to Mohammadreza Barzegaran

Re: sinusoidal voltage to time dependent solver

Hi

if you are studying a steady state sinus, it often far easier and quicker to use the frequency domain solver than a true transient, transient behaviour and sustained sinus excitation is not fully the same, because you have all the transient effects from your inperfect BC's in the time solver

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Good luck
Ivar

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January 28, 2013 8:42pm UTC in response to Mohammadreza Barzegaran

Re: sinusoidal voltage to time dependent solver

Hi

have you got your model running ?
At least you could reduce the overall air size to some diam 0.4 ad somewhat longer than you imported model, then add some 4 cm of infinite elements and set them up for cylindrical coordinates. But I'm not sure what you expect to see ?

then you define the ima,b,c over all the domains, but they have some sense only locally, I would rather use the formula directly in the multi-Turn Coil BCs

Anyhow for continuous AC you should use the frequency sweep mode at a fixed frequency of 60 Hz and then give the amplitudes as complex values (physors) for the phase instead of the wv1,2,3(t) approach. The time domain is only useful for a transient turn on, and in MF you do not get any ringing as the 2nd time derivative physics is ignored


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Good luck
Ivar

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February 4, 2013 6:14am UTC in response to Mohammadreza Barzegaran

Re: sinusoidal voltage to time dependent solver

Hi

the phasor approach (complex amplitudes), should work check the the doc

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Good luck
Ivar

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