State space decoupling control design methodology for switching converters

Abstract

This paper derives a new approach for analyzing dc-dc converters for feedback control design. The control-to-output voltage transfer function of the converters, usually predicted by averaging models, and the classical feedback control techniques are replaced by the state space average state block diagram analysis. These state block diagrams are obtained for state space averaging matrixes of the converters combined with their continuous conduction mode differential equations. This decoupling technique yields first order control transfer functions allowing easier synthesis of controllers. The disturbance rejection properties of the controller are analyzed and improved by disturbance input decoupling. The technique is applied to buck converters, and the controllers demonstrate good transient response compared to classical voltage controllers. The structure is easy implement with relevant applications in integrated circuit manufacturing and general industrial environments.