  We focus on the connection between the internal dynamo magnetic field and the
stellar wind. If the star has a cyclic dynamo, the modulations of the magnetic
field can affect the wind, which in turn can back-react on the boundary
conditions of the star, creating a feedback loop. We have developed a
2.5-dimensional numerical set-up to model this essential coupling. We have
implemented an alpha-Omega mean-field dynamo in the PLUTO code, and then
coupled it to a spherical polytropic wind model via an interface composed of
four grid layers with dedicated boundary conditions. We present here a dynamo
model close to a young Sun with cyclic magnetic activity. First we show how
this model allows to track the influence of the dynamo activity on the corona
by displaying the correlation between the activity cycle, the coronal structure
and the time evolution of integrated quantities. Then we add the feedback of
the wind on the dynamo and discuss the changes observed in the dynamo symmetry
and the wind variations. We explain these changes in terms of dynamo modes : in
this parameter regime, the feedback loop leads to a coupling between the dynamo
families via a preferred growth of the quadrupolar mode. We also study our
interface in terms of magnetic helicity, and show that it leads to a small
injection in the dynamo. This model confirms the importance of coupling
physically internal and external stellar layers, as it has a direct impact on
both the dynamo and the wind.
