Robust H∞ Control for PWM Boost Converters Subject to Aging Capacitor Conditions

Abstract

Electrolytic capacitors are extensively used in DC-DC power converters and consist of a major source of concern about system reliability. Although these components are heavily affected by aging, conventional modelling and control design for converters often disregard the uncertainty on capacitor parameters. In this paper, the robust control problem for boost converters is addressed with the derivation of a more comprehensive model. Although the modelling complexity is higher, the simplicity of linear state feedback control is preserved and the synthesis algorithm is performed by a LMI-based optimization problem. Moreover, the proposed control scheme requires state estimation, which is performed online as part of an identification system. Simulation results are presented and indicate the validity of the proposed concept.