  In this work we study the asymptotic behavior of the solutions of a class of
abstract parabolic time optimal control problems when the generators converge,
in an appropriate sense, to a given strictly negative operator. Our main
application to PDEs systems concerns the behavior of optimal time and of the
associated optimal controls for parabolic equations with highly oscillating
coefficients, as we encounter in homogenization theory. Our main results assert
that, provided that the target is a closed ball centered at the origin and of
positive radius, the solutions of the time optimal control problems for the
systems with oscillating coefficients converge, in the usual norms, to the
solution of the corresponding problem for the homogenized system. In order to
prove our main theorem, we provide several new results, which could be of a
broader interest, on time and norm optimal control problems.
