Reduction of the sensitivity of an optimal control system to plant parameter variations

Comparison between open- and closed-loop implementations have been made by Youla and Dorato [1] and Kriendler [2], etc., but the implementation with two degrees of freedom does not appear to have been considered. An attempt to reveal the potentiality of the implementation with two degrees of freedom in applying the configuration to reduce various sensitivities of an optimal system due to plant parameter variations is presented.