A numerically reliable approach to robust pole assignment for descriptor systems

Abstract

We propose a general, numerically reliable computational approach to solve the pole and eigenstructure assignment problem for descriptor systems. In the multi-input case, the proposed approach addresses the intrinsic non-uniqueness of the pole assignment problem solution by simultaneously minimizing the sensitivity of the feedback gain and of closed-loop eigenvalues. For this purpose, a minimum norm robust pole assignment problem is formulated and solved as an unconstrained minimization problem for a suitably chosen cost function. By using a generalized Sylvester equation-based parameterization, an explicit expression of the gradient of the cost function is derived to allow the efficient solution of the minimization problem by using powerful gradient search-based minimization techniques.