Robust pole assignment for descriptor systems

By using a generalized Sylvester equation based parametrization, three minimum norm robust pole assignment problems for descriptor systems are formulated as unconstrained minimization problems for suitably chosen cost functions. The derived explicit expressions of the gradients of the cost functions allow the efficient solution of the minimization problems by using powerful gradient search based minimization techniques. We also discuss how requirements for a particular Jordan structure of the closed-loop state matrix or for partial pole assignment can be accomodated with proposed approach