A class of Lagrange-Newton-SQP methods is investigated for optimal control
problems governed by semilinear parabolic initial-boundary value problems.
Distributed and boundary controls are given, restricted by pointwise upper
and lower bounds. The convergence of the method is discussed in appropriate
Banach spaces. Based on a weak second order sufficient optimality conditio
n for the reference solution, local quadratic convergence is proved. The pr
oof is based on the theory of Newton methods for generalized equations in B
anach spaces.