Robust Control Design for Boost and Buck-boost Converters

Switched-mode power supplies are important elements in telecommunication systems and electric products. This work considers variations of the boost and buck-boost converters operating in continuous inductor current mode (CCM). In this mode, they require time-varying system models, however, they can be modeled as time-invariant systems by representing the variations in system parameters as model uncertainties. A multiplicative uncertainty is used to model the system variability. The boost and the buck-boost converters are non-minimum phase systems that will have inherently degraded system robustness. The main task in this thesis is to design a feedback controller that guarantees robust stability and robust performance for the closed-loop system.;The boost and the buck-boost converters may be considered as a multiple-input multiple-output system (MIMO), and consequently the controller should have a MIMO structure as well. The mu-analysis technique is used to analyze the system and to evaluate the system robustness. The control configuration takes the form of Voltage Mode Control (VMC).PID and Hinfinity controllers are designed to achieve robustness, nominal and robust stability and performance.;Key Words Switched-mode power supplies, non-minimum phase system, Hinfinity control, PID control.