Robust discrete-time output feedback stabilization of integrator chains

This work proposes a discrete-time output feedback controller to stabilize an integrator chain system in the presence of measurement noise and external disturbances. Besides, two structural systems are considered, the first one is a system with a saturation in the control input. The second one is a system with an unbounded input. Since the system output is supposed to be periodically sampled and noisy, a discrete-time filtering observer is designed. Hence, using the output of the observer, a discrete-time controller is derived. The closed-loop system convergence and robustness analysis are also presented. Simulation results are performed, aiming to illustrate the main characteristics of the proposal, including comparisons between the closed-loop system with an explicit and implicit discrete-time observer. Finally, having proved the features of the implicit realization, the controller with an implicit differentiator is implemented to control a DC-DC buck converter.