T. Mita et al., STATE FEEDBACK H-INFINITY H-2 CONTROL, IEICE transactions on fundamentals of electronics, communications and computer science, E75A(3), 1992, pp. 299-306
H(infinity) control theory provides a systematic frequency shaping met
hod of control systems. The existence condition of the solution for so
called standard H(infinity) control problem and the form of the H(inf
inity) controller are derived in 1989. One of the most important featu
re of the controller is that it has many free parameters which can be
chosen independently of the H(infinity) control. On the other hand the
re is a criticism that the time response of prototypal H(infinity) con
trol systems is slow. Therefore in this paper we introduce an H-2 cont
rol optimization by taking advantage of the free parameters to expect
the improvement of the time response of the H(infinity) control system
. In this paper we consider state feedback case. The free parameters o
f state feedback H(infinity) controller are not directly obtained from
well known results since this problem is a kind of non-standard probl
em. Therefore, in the first place, we will get them via reviewing the
FI (ful information) case. Then the free parameters of the state feedb
ack H(infinity) controller are shown based on the corrected Fl solutio
n. These parameters are next used to optimize an H-2 control objective
in the H(infinity) control system.