Control of sub-harmonic oscillation in peak current mode buck converter with dynamic resonant perturbation

In this paper, a dynamic resonant perturbation (DRP) method is proposed to control sub-harmonic oscillation in a peak current mode controlled buck converter. Different from the traditional non-feedback resonant parametric perturbation method, the proposed DRP method extracts an approximate sinusoidal control signal from the output voltage. The self-stabilizing condition for the designed control signal is presented, and its analog circuit implementation is given as well. Furthermore, the system stability boundary is obtained by investigating the system eigenvalues, and the control parameter is effectively determined. The presented simulation and experiment results show that the proposed DRP method eliminates sub-harmonic oscillation without sacrificing the peak value of the inductor current and features with a self-stabilizing characteristic for external condition changes. Copyright (c) 2014 John Wiley & Sons, Ltd.