ABSTRACT
This chapter presents a decentralized adaptive control scheme. It addresses output tracking of a class of interconnected time-delay subsystems with the input of each loop preceded by an unknown dead-zone. Each local controller is designed using the backstepping technique and consists of a robust control law and new updating laws. Unknown time-varying delays are compensated by using appropriate Lyapunov-Krasovskii functionals. The results are often obtained via linear matrix inequalities. However, little attention has been focused on nonlinear time-delay large-scale systems. In a decentralized state-feedback variable structure controller was proposed for large-scale systems with time delay and dead-zone nonlinearity. However, the time delay is constant and the parameters of the dead-zone are known. The nonlinear time-delay functions are unknown and are allowed to satisfy a nonlinear bound with unknown parameters. By using smooth differentiable functions, practical control can be carried out in the backstepping design to compensate the effects of unknown interactions, unknown time delays and unknown dead-zones.
