Advice on pre-fault voltage factor for short circuit calculation

mrsilvabr commented 5 months ago

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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 commented 4 months ago

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

mrsilvabr commented 4 months ago

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 commented 4 months ago

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. https://github.com/e2nIEE/pandapower/blob/ed0e8e534193927b6bfe0d5a31fd8014e7dc0cca/pandapower/build_bus.py#L716

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

mrsilvabr commented 3 months ago

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.

gbanerjeefraunhofer commented 23 hours ago

Dear @mrsilvabr ,

We have been waiting for your response on this issue since 20th Aug. We would be glad to know if you have any further information or progress on it.

Thanks and regards, Gourab Banerjee

e2nIEE / pandapower