PSSe have an add-on tool to perform PV analysis. Using such tool, transfer of power between areas can be tested and at each incremental power transfer (say 100 MW), contingencies are evaluated. The run stops when a contingency does not converged, meaning the maximum power transfer between those areas has been reached, or when the transfer reach its maximum as defined in the set up. The PV study set up (similar to ACCC) uses SUB, CON and MON files.
In python, the simulation of a PV study requires two loops. The outer loop sets/creates a case at the required power transfer level between the selected region and the inner loop evaluates all the contingencies. ACCC could be used here, instead of the inner loop. On the power transfer methodology, it can be
"Gen-to-Gen", scale up generation at the sending region and scale down generation at the receiving region, or
"Gen-to-Load", scale up generation at the sending region and scale up load at the receiving region or
"Load-to-Load", scale down load at the sending region and scale up load at the receiving region
In general, the python approach provides flexibility and control of the study but it up to the user to perform the checks needed for a sound study (selection of gens or loads participating in the power transfer process, check for violations and resolution before entering the contingency process, criteria to declare a voltage collapse condition, etc.)
Search this forum for "PV Analysis" or "SUB file" to find examples on the definition of subsystems (a.k.a. source and sink). Download "pv.zip" from my public google site, to run a demo pv study on the savnw case (it uses data available in the folder 'example' of the PSSe installation folder.)
