1998 Volume 11 Issue 1 Pages 35-40
In this paper, a design method of a single-input single-output PID controller for H∞ control problem is proposed. Since the H∞ norm constraint consists of an internal stability condition and a frequency domain condition on the jω axis, the solution set of the PID gains for the H∞ control problem is given on a parameter plane as the intersection of the two sets which satisfy the above two conditions. As for the computation of the latter set, two methods are proposed. One is a method in which the set is directly computed from the frequency domain condition, and the other is a method in which the set is computed by using the parametrization of all the H∞ control solutions.