http://www.paper.edu.cn
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Control of low frequency oscillation in one-cycle- controlled
Boost converter with the current feedback
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Wang Faqiang, Zhang Hao, Ma Xikui
State Key Lab of Electrical Insulation & Power Equipment, School of Electrical Engineering, Xi’an
Jiaotong University, Xi’an (710049)
Abstract
In this paper, the current feedback method is presented to control the low frequency oscillation in
one-cycle-controlled Boost converter to operate in period-1 state. The stroboscopic map of the
one-cycle-controlled Boost converter with current feedback is obtained by using the data-sampling method.
Based on the presented stroboscopic map and the help of the loci of eigenvalues of the Jacobian matrix, the
stable range of feedback gain is obtained. Finally, the results of simulation and experiment confirm the
correctness of the theoretical analysis and the validity of the proposed method.
Keywords: Low frequency oscillation; Current feedback; One cycle control; Boost converter
1. Introduction
DC-DC converters, which are practically nonlinear systems, are widely used in various fields,
such as industry, communication, aerospace, civil applications, etc. So, in the past few decades, the
modeling and dynamical behavior of the converter, and their control methodologies have attracted
increasing interests [1-9]. Especially, intensive investigations in DC-DC converters have shown that
the complex nonlinear phenomena including bifurcations, low frequency oscillation, and chaos can
easily come when the circuit parameters are not fit [3-4]. However, in most practical situations, the
required stable operation of DC-DC converters is period-1, and any bifurcations, low frequency
oscillation, or chaos is regarded as being undesirable and should be avoided. Therefore, in recent years,
how to control these complex behaviors to be stable has been a focal topic and many different
techniques and methods have been proposed to achieve the control of complex behaviors in DC-DC
converters. Such as, OGY method [5], time-delayed feedback [6], optimal resonant parametric
perturbation [7], etc. Unfortunately, these aforementioned methods mainly focus on chaos control in
DC-DC converters, while little attention has been paid to the other complex behaviors control in
DC-DC converters. But, the complex behaviors except chaos can also easily happen in DC-DC
converters and affect the performance of DC-DC converters. For example, when the low frequency
oscillation had happened in DC-DC converter, it will not only affect the stability of the output voltage,
but also decrease the efficiency of the conversion. Therefore, studying on some new approach to
realize the control of the low frequency oscillation in DC-DC converters to operate in period-1 is very
important and valuable.
On the other hand, from the Ref [8], we know that the one-cycle-controlled Boost converter can
be stable in one period in the discontinuous conduction mode (DCM), but it may not be stable in the
continuous conduction mode (CCM) and the low-frequency oscillation phenomena occurs due to the
value of the inductor current can not be negative for the function of the diode. Thus, in this paper, the
one-cycle controlled Boost converter operates in CCM is only considered and the current feedback is
proposed to control the low frequency oscillation. The stroboscopic map of the system with current
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Project Supported by Specialized Research Fund for the Doctoral Program of Higher Education (Grant No.
20050698004).