Dual Core Control of an on board Charger

Hello,
The demo model provided for the dual-core control of an onboard Charger has some conversion between DAB and Inveter connection, as shown in the following figure.

I am confused about how that develops. Can you please help me understand it or give me some resources to observe?

See the “Distributed Realtime Simulation” section of the RT Box User Manual. From the Manual:

Note that in an offline simulation a Delay block is necessary in at least one direction of communication to prevent algebraic loops.

This is also discussed in the System Splitting for Distributed Real-Time Simulation tutorial on the Plexim tutorial page.