Advice on pre-fault voltage factor for short circuit calculation

[mrsilvabr]

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Issue

Hi there
I am using the software for short circuit levels investigations. I came upon the following situation:

circuit(violet2)
bus 0 - 69 kV
bus 1 - 69 kV
external grid (69 kV, 1000 MVA, rx=22)
external grid----->bus0(source_1)-->line(CB27_LT)-->bus1(T2PRIM).

It is a very simple circuit, downsized from fig. 4-1 - IEEE Std 551-2006 - Violet Book
The short circuit level at bus1(T2PRIM) evaluated by hand is 6797 A. Essentially the same as resulting from other packages.
The result from Panda Power is 7135 A, which I found to be 1.05 x 6797. Now I know that, given the 69 kV system, a factor of 1.1 should be applied as per the IEC 69909 recommendation. That should give me 7476 A in Panda Power.

Would someone comment on this?

Thanks

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[vogt31337]

I don't do short ciruit investigations. So is this to be considered a bug? If so could you write a test?

[mrsilvabr]

Thank you for the interest. As far as I see, the calculation by hand is the best test I can do.
I am not knowledgeable enough to check the internal routines of the software.
Regards

[gbanerjeefraunhofer]

Dear @mrsilvabr ,
please provide your hand calculation and your pandapower calculation code so we can evaluate the difference.
In pandapower, C factor is considered as 1.1 based on IEC60909 code for the buses over 1 kV voltage level.
Please follow the attached link and check your input parameter accordingly.

pandapower/pandapower/build_bus.py

Line 716 in ed0e8e5

def _add_c_to_ppc(net, ppc):

Please recalculate, check and compare the result and get back to us if you have still mismatch result.

[mrsilvabr]

gbanerjeefraunhofer, thank you for the answer.
I have been involved in a new project, with my hands an head full. I will do as you instructed me but it is going to take a few weeks.
I will get back as soon as I can.