Error minimization in multiple-connected subsystems

A set of fully interconnected
n
th order discrete-time subsystems is considered. The subsystems errors are minimized with respect to the coupling, feedback, and forward gain parameters, using nonlinear programming. It was demonstrated that the error functions for subsystems of the third order and higher, are independent of the coupling gains and part of the feedback gains. Increasing the number of subsystems tends to increase the error cost function.