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Convergence problems in time dependent simulations
Posted 2012年7月31日 GMT-4 08:57 Low-Frequency Electromagnetics Version 4.3 1 Reply
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Hello,
does anyone has experience how to solve convergence problem
in time dependent simulations ? I tried to produce square wave
input waveform from a sine wave input and using two diodes to
cut the waveform. This should be a straightforward but not necessary
the best method to produce square wave. The message I got "nonlinear
solver did not converge, ..., last timestep is not converged". Any specific
solver parameter sets which could help ? A better way to generate square
or PWM waveform ?
does anyone has experience how to solve convergence problem
in time dependent simulations ? I tried to produce square wave
input waveform from a sine wave input and using two diodes to
cut the waveform. This should be a straightforward but not necessary
the best method to produce square wave. The message I got "nonlinear
solver did not converge, ..., last timestep is not converged". Any specific
solver parameter sets which could help ? A better way to generate square
or PWM waveform ?
1 Reply Last Post 2012年8月2日 GMT-4 13:50
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Posted:
1 decade ago
Hi
there are many things to follow with "square" periodic time series, it has been extensively discussed on the FORUM try a search. Amon which: use rather a continuous (smooth) function with a repetition option (analytical function), then be sure you have a few time steps during the constant period BUT also the rise times, not to say. Then be sure you set the "time stepping" to intermediate or strict and NOT to automatic, which might skip periods. Finally, do not foret to ensure you initial conditions are well defined and valid for t=0 settings of your BC
--
Good luck
Ivar
there are many things to follow with "square" periodic time series, it has been extensively discussed on the FORUM try a search. Amon which: use rather a continuous (smooth) function with a repetition option (analytical function), then be sure you have a few time steps during the constant period BUT also the rise times, not to say. Then be sure you set the "time stepping" to intermediate or strict and NOT to automatic, which might skip periods. Finally, do not foret to ensure you initial conditions are well defined and valid for t=0 settings of your BC
--
Good luck
Ivar