Asymptotic disturbance rejection for Hammerstein systems with passive linear dynamics

In this paper we present control algorithms for stabilization and asymptotic disturbance rejection for Hammerstein systems with positive-real linear dynamics. To do this, we extend the nonlinear controller modification technique to include plant disturbances. The controllers involve novel Lyapunov functions that confine the estimates of the disturbance bound to the positive real numbers. These estimates are then used to construct high-gain switching controllers which guarantee convergence of the plant output while accounting for input nonlinearities