The engine room diagram is AI generated BS. Phase a connects to phase b. No one is separating battery banks by phase in a 3 phase system. No explanation of why they chose to mention a delta connection at 19.9kV when 19.9kV is the line to neutral voltage of an ANSI C84.1 34.5kV system which is wye connected giving you 34.5kV line to line. Clearly a lineman or EE wrote this /s.
And my personal favorite is the load priority numbering where the towns people are last in line behind the AI data center employees who are themselves lesser than the holy AI machinery they tend. The tokens must flow.