Hi Babak,
The "Automated Grid Power Target" controller does seek to keep the grid power at or below the target power you specify, but may fail in some instances, particularly if other constraints are violated (minimum or maximum state-of-charge, exceed the maximum C-rate (current through-put), etc). Do to the non-linearity of the voltage curve, it is also possible that the amount of power dispatched will be less than or more than the amount requested, as the voltage changes.
Nevertheless, if the target is being violated and you still don't understand why, I'm happy to to take a look at your project. In which case, you can post here, or email me at This email address is being protected from spambots. You need JavaScript enabled to view it..
Best regards,
Nick DiOrio