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I have a script that runs ACC on my .sav files, then with the use of pssarrays.accc_summary() is able to loop through the contingencies, bus and branch information, etc, to check for thermal loading and voltage issues. It then spits all the results nicely into Excel.

I'm wanting to take this a step further and do some cascading checks. Assuming a branch (line or transformer) with loading above 120% may trip on instantaneous overcurrent, and/or load on a bus with less than 85% voltage would trip, I want to identify any branches or buses that meet this criteria, then have my script develop a new CON file from the original contingency event and add steps for tripping the branches and/or load on the buses. It actually works quite nicely to pull the overloaded line or two-winding transformer data, and write a new step to trip the element. Also, works nicely to pull the bus data and write a new step to set the load at the bus to 0%.

However, my issue is when I have a three-winding transformer that overloads above the threshold. The branch label data is in the form "AAAAAA BBBBBBBBBBBBCCCCCC XXXXXX YYYYYYYYYYYYZZZZZZ DD", where: AAAAAA = frombusnumber, BBBBBBBBBBBB = frombusname, CCCCCC = frombusvoltage, XXXXXX = tobusnumber, YYYYYYYYYYYY = tobusname, ZZZZZZ = tobusvoltage, DD = circuitid. The tobusnumber is set as "3WNDTR", the tobusname is set as the transformer name, and the tobusvoltage is set as "WND 1" or "WND 2" depending on the winding. So I am unable to get the other two winding bus numbers from using pssarrays.acccsummary().

My questions/thoughts are: Does anyone have any experience with getting three-winding transformer bus data from ACC results? Does anyone know how to get three-winding transformer bus data when only given the transformer name? Is anyone aware of another option in setting up the CON file to specify a three-winding transformer without having all three bus numbers?

I'm thinking that my best option might be to setup a table of all of my three-winding transformers by name to refer to in order to grab the bus numbers for each winding.

Thanks in advance.