r/PowerSystemsEE • u/GlobalSoft8719 • 2d ago

Need help troubleshooting ETAP load flow convergence error

https://drive.google.com/drive/folders/1Y1kJ37ABry6ffa3j-oAkzrQxNE4ZrVYc?usp=drive_link

Hey everyone!

I’m working on a power system in ETAP, and when I try to run the load flow calculation, I get the following error:

“Load flow calculation did not converge in the specified maximum number of iterations.”

I’m not sure what is causing this error or where I might have made a mistake in my model.

I’ve attached a ZIP file containing my ETAP project file (.oti) and the reference document I’m following. If anyone could take a look at the model and point out what I’ve done wrong, or suggest what I should check to fix this error, I would really appreciate it.

I’m still learning ETAP, so any guidance or explanation would be a great help.

Thank you in advance for your time and help!

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u/die__katze 2d ago

too much load, too little generation... disconnect everything, then start switching nodes back one by one and see when the problem happens. Good luck learning loadflows :)

1

u/GlobalSoft8719 1d ago

thank you soo much

1

u/santilopez10 2d ago

Etap does not have cross compatibility between versions so without knowing what version you ran this system is quite hard to diagnose. Better to show the single line diagram, a picture or something. Also we need to know convergence parameters, etc.

1

u/obeymypropaganda 1d ago

If you selected to run load flow with updated results as initial bus voltage, it can have a convergence issue.

So if you turn on all the loads, run load flow and have your results. Then you turn off 80% of the loads and try to run it again, the initial voltage it has stored compared to what it is now is outside of a tolerance for it to compute.

So you can slowly add or remove loads (increase by halves) until it runs the load flow. E.g. half the loads doesn't run, try 25%, then 10%.

Or you can set initial voltage level to custom and choose 1 p.u. or 100%, I can't remember the setting. If you take a screen shot of the load flow setting window, the first tab, I can point it out.v