Okay, your main problem is that you only have one subsystem defined ('A'). Now, PV analysis is inherently different to QV analysis. When performing PV analysis, you need to define a source and a sink. As the process is progressed, more power will be transferred through a cutset of lines by adjusting the load/generation in the source and sink subsystems.
Your subsystem (SUB) file should be something like this:
SUBSYSTEM 'SOURCE'
BUS 100
END
SUBSYSTEM 'SINK'
BUS 101
BUS 102
BUS 103
BUS 104
BUS 105
BUS 106
END
END
Your MON file can then reference the SINK subsystem (or SOURCE if you want to include that too):
MONITOR LINES IN SUBSYSTEM SINK
MONITOR VOLTAGE DEVIATION ALL BUSES 0.1
END
END
Finally, your contingency file might look like this:
SINGLE BRANCH IN SUBSYSTEM 'SINK'
SINGLE BRANCH IN SUBSYSTEM 'SOURCE'
END
The things to be careful about:
- Take care selecting your source and sink subsystems. You should choose a sink on one side of your cutset, and a source on the other. Voltage will likely collapse in the sink.
- In the "transfer dispatch method" section, you can determine whether you want to increase flow on your cutset by controlling generation or load in each of the source and sink areas. Play with these if you are getting errors (since your network is so small, you will need to make sure you have load or generation in the area that you pick—For the above example, I picked DFAX generation for both).
- Make sure you select your "SOURCE" subsystem and "SINK" subsystem in the subsystem selection above the DFAX file (which you will need to regenerate).
It sounds like it might relate to how your source and sink subsystems are defined. Can you show your subsystem definition, and confirm that they have in-service generators and loads? If you are running the PV via Python, please include that line of code too.