2004 Volume 17 Issue 9 Pages 363-370
In this paper, a new design method for robust I-PD controller by using Pareto-optimality is proposed. The proposed design method is formulated as a two-objective optimization problem in which optimization of the settling time and damping ratio is translated into a pole assignment problem. The uncertainties of the plant are represented as a polytope of polynomials, and the computational cost is reduced by using the edge theorem. The genetic algorithm is applied to optimize this problem because of its multiple search property. In order to demonstrate the effectiveness of the proposed design method, we applied the proposed design method to a magnetic levitation system and compared our method with the design method based on the generalized ISE (Integral of Squared Error) criterion.