Abstract
In this paper, a search method for a fixed-order controller that satisfies the standard H∞ control problem is proposed. This is a descent method that gives a sequence of the stabilizing controllers so that the H∞ performance function may be monotonically non-increasing. A frequency-dependent LMI(linear matrix inequality) with respect to the coefficient matrices of the controller is derived from the H∞ norm constraint. This method is applicable to the frequency response of the plant.
