Open AccessLow-frequency oscillation in digitally controlled DC-DC Buck converters
Author(s) -
Zhang Xiao-Tian,
Xikui Ma,
Hao Zhang
Publication year - 2008
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.57.6174
Subject(s) - buck converter , oscillation (cell signaling) , bifurcation , physics , amplitude , frequency domain , converters , low frequency oscillation , eigenvalues and eigenvectors , low frequency , control theory (sociology) , stability (learning theory) , mathematical analysis , computer science , voltage , mathematics , optics , nonlinear system , power (physics) , electric power system , genetics , control (management) , quantum mechanics , astronomy , artificial intelligence , machine learning , biology
The z-domain model of digitally controlled Buck converter is derived by only considering the effect of sampler-and-holder. Based on the z-domain model, the cause of the low-frequency bifurcation is analyzed. The location and type of the bifurcation point when a system loses stability is predicted in terms of the system eigenvalues. Moreover, the frequency and the amplitude of the low-frequency oscillation, i.e., the wave equations, are deduced. These theoretical results are verified by PSpice simulations.