Robust control with optimization of robustness index

The paper considers a problem of robust control system synthesis based on the modified algorithm of Coefficient Diagram Method (CDM) with robustness index optimization. The proposed solution is expected to enable improvement of system robustness against parametric uncertainty. As a measure of assessment an aim function (robustness index) defined for the system with an additional filter block is introduced. Parameters of this block are calculated with the use of Hungarian (Munkres) algorithm. The controller synthesis is presented in a theory and on an example. A description of the proposed, modified CDM algorithm and optimization procedure are given, as well as the specification of the coefficient diagram (CD) - a tool for assessment of system stability, robustness and dynamics. The design problem is formulated for the system with stable nonminimum phase plant. Paper presents results of optimization and simulation tests performed in MATLAB 7.0 environment, which confirmed the efficiency of the proposed solution.