If my DC renewable generator ( wind turbine, PV ecc) doesn't produce electricity when the state of charge of the battery bank is 100% as it has a its own control, why is there an excess electricity production by this generator ?

I think you are saying that your DC renewable power sources have controllers that reduce their power output when necessary to avoid excess electricity.

HOMER does not model such a situation; it assumes that the power produced by a renewable power source depends only on the renewable resource, and not on the state of charge of the battery.