Title :
Design of a robust voltage controller for a buck-boost converter using μ-synthesis
Author_Institution :
Dipt. di Elettronica e Inf., Padova Univ., Italy
fDate :
3/1/1999 12:00:00 AM
Abstract :
Proposes the structured singular value (μ) approach to the problem of designing an output voltage regulator for a buck-boost converter with current-mode control. This approach allows a quantitative description of the effects of reactive components´ tolerances and operating point variations, which strongly affect the converter dynamics. First, a suitable linear converter model is derived, whose parameter variations are described in terms of perturbations of the linear fractional transformation (LFT) class. Then, μ-analysis is used to evaluate the robustness of a conventional PI voltage regulator with respect to the modeled perturbations. Finally, the approximate μ-synthesis procedure known as D-K iteration is used to design a robustly performing regulator. Simulation results are presented, describing the small and large signal behavior of a reduced order approximation of the μ-synthesized controller
Keywords :
DC-DC power convertors; control system synthesis; robust control; voltage regulators; μ-synthesis; D-K iteration; buck-boost converter; conventional PI voltage regulator; converter dynamics; current-mode control; linear converter model; linear fractional transformation class; operating point variations; reactive components; reduced order approximation; robust voltage controller; robustness; structured singular value approach; Control systems; DC-DC power converters; Matrix converters; Regulators; Robust control; Robust stability; Robustness; Transfer functions; Uncertain systems; Voltage control;
Journal_Title :
Control Systems Technology, IEEE Transactions on