Output feedback H-infinity control for buck converter with uncertainty parameters

This paper addresses the problem of output feedback H_∞ controller design for buck converter with multiple parameters uncertainty. The parameter uncertainty model of buck converter is built by method of first-order Taylor approximation. Based on the model, the solvability condition for the existence of output feedback H_∞ controller is derived in the form of linear matrix inequality according to H_∞ control theory. The designed controller is such that the closed-loop system is asymptotically stable when several parameters change in a small range. And the closed-loop system has an H_∞ disturbance attenuation upper bound. Theoretical analyses and simulation results demonstrate the validity and effectiveness of the proposed control strategy.