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Why is my steady state analysis of a dc-dc converter aborted due to errors?

+1 vote
59 views
Dear Community,

As I am trying to get the frequency response of DC/DC converter,exactly the control to error transfer function Vout(s)/Verr(s) (Verror=Vref-Vout). after launching the analysis I get this error message as shown in the image attached.

best regards,
asked Feb 16 by EMdude (69 points)

1 Answer

+2 votes
 
Best answer

It didn't find a steady state. This means your system takes too long to get to the steady state from simulation start.

A simple fix would be to switch to "Stored system state" in the Initialization tab of the simulation preferences. You must store a state where the system is in steady state. For example after a normal simulation.

Another possibility is to set the number of init cycles in the Analysis Tools dialog.

I strongly advise using the "Help" button in the Analysis Tools to get to the documentation. There you find:

[...]Number of init. cycles
The number of cycle-by-cycle simulations to be performed before the Newton iterations are started. When an analysis fails to converge because the starting point was too far from the steady-state solution, this parameter can help to get better starting conditions. The default is 0. [...]

Cheers 

Falk

 

answered Feb 16 by Falk Kyburz (153 points)
selected Feb 22 by EMdude
Thanks Falk for the hint. I have solved this problem by giving a number 25 for the number of iterations but I am bit confused whether it will impact my result or has no impact.

I have also got another issue after this my body shows only half of the frequencies, not the whole frequencies as you can see in the image.

just a detail, I have placed my perturbation between the PI controller and the subtraction block
...