Solutions to a class of nonstandard nonlinear H∞ control problems

We present a new solution to H-infinity, control problems for nonlinear plants whose measurement output is of dimension larger than the dimension of the external input. This problem is, under proper assumptions, transformed to stabilizing by means of output injection, and solving a Hamilton-Jacobi inequality arising in the H, state-feedback control. General sufficient solvability conditions are given. Explicit solutions are available in the local case. The issue of the controller order is addressed and a reduced order controller is obtained.