Discrete-time current observer design and hybrid output feedback control for continious-time nonlinear systems
The work presented in this thesis addresses observer and feedback control designs for both continuous-time linear and nonlinear systems and their discrete equivalents. A class of nonlinear systems are considered for the design of a globally convergent observer and feedback control. A continuous-time linear and nonlinear system is discretized using ZOH into its discrete-time equivalent to analyze the dynamics and stability of the systems and establishing the sufficient conditions necessary for stability. A delayed observer and current observer for discrete-time systems are first considered and are constructed from the discretized system in order to analyze the stability. After the observer design, the focus shifts to the state and output feedback control which is applied using both continuous and discrete feedback to give a hybrid control. The discrete-time controller is applied to the continuous-time system and the results are analyzed.