Ground Fault protection for a wye-wye transformer 1

[nerb31]

I am working on a ground o/c coordination and i am having a bit of trouble on the wye-resistor grounded wye-solid grounded with delta tertiary transformer. Solidly grounded is connected at 230kV while the resistor grounded (50ohms) is connected at 34.5kV. Now, my questions is:
1. Will a ground fault of say 1000A at 230kV side appears as 1000A also at the 34.5kV side since both neutrals are grounded on the same grounding system(im a bit confused on the limit of the NGR at 400A)?

i have googled for answers and come up with a few topics here about wye-wye transformers but not exactly answers my question.
appreciate any inputs.

thanks

 

[EddyWirbelstrom]

I created a model of the system using SKM/PTW software.
Attached file shows the results for 25 MVA Generator and Transformers. 3 Wndg Xfm Pri-Sec = 25MVA, PriTert and TertSec = 1 MVA
If you send the actual MVA values and pos, neg, zero sequence impedances I will enter them and run the short-cct study.
Also attached is the zero-sequence impedance network.
For a SLG fault on the 34.5kV system, the attached zero sequence impedance diagram shows two zero sequence paths in parallel.

 

[odlanor]

EddyWirbelstrom.
I have a different interpretation!
see Annex

 

[EddyWirbelstrom]

Nerb31
What are the +, -, and 0 sequence impedances of the 230kV network ? Does the 230kW network have motor contributions ?
What are the generator reactances and MVA rating ?
What are the MVA and +, -, and 0 sequence impedances of the transformers ?
What are the P-S, P-T, S-T MVA ratings and + and 0 sequence impedances on their individual ratings ?

Odlanor
My zero sequence diagram assumed the network to be connected via a Dyn transformer.
Can you scan the page previous to t he Figure 4.16 ?

 

[odlanor]

EddyWirbelstrom (1)