How do you simply test and verify a battery's charge and discharge capability when connected to a network in Simulink?

I would like to simply test and verify the charge and discharge capability of a battery when connected with an average-value VSC and a three-phase network. Whenever I did it, I always experience no behavior changes from the battery/network or I encounter convergence errors. The image below shows what connections I've done so far with a battery pack, an average-value VSC and IEEE-9 bus network. However, I am unsure what to connect to the modwave input of the VSC. A simpler network could help me better understand how each component interacts with one another.

I have seen the peak shaving example (https://www.mathworks.com/help/simscape-battery/ug/peak-shaving-bess.html), but I find it too complex to replicate, since it already integrates control systems.

Any form of help is appreciated. If you are an expert in this field, I would like to keep in contact with you. Thank you!