TY - JOUR
T1 - Small-Signal Models with Extended Frequency Range for DC-DC Converters with Large Modulation Ripple Amplitude
AU - Li, Xin
AU - Ruan, Xinbo
AU - Jin, Qian
AU - Sha, Mengke
AU - Tse, Chi K.
N1 - Funding Information:
Manuscript received August 15, 2017; revised October 16, 2017; accepted November 9, 2017. Date of publication November 14, 2017; date of current version June 22, 2018. This work was supported by the National Natural Science Foundation of China under Award 51277097. Recommended for publication by Associate Editor R. Redl. (Corresponding author: Xinbo Ruan.) X. Li, X. Ruan, Q. Jin, and M. Sha are with the Center for More-Electric-Aircraft Power System, College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 211106, China (e-mail: lixin_1989@ nuaa.edu.cn; [email protected]; [email protected]; shamengke@nuaa. edu.cn).
Publisher Copyright:
© 1986-2012 IEEE.
PY - 2018/9
Y1 - 2018/9
N2 - Application of pulse width modulation (PWM) is known to produce sideband effects. The accuracy of the models of dc-dc converters can be improved if essential information of the sideband effects of PWM can be incorporated. In this paper, the aliasing effect of the sideband components on the closed-loop control is analyzed, and an effective representation of the transfer function of the pulse-width modulator is derived. Applying this transfer function to the dc-dc converter, an extended-frequency-range small-signal model is obtained, which can be conveniently used for deriving the loop gain of a PWM-controlled dc-dc converter. Furthermore, for wideband control applications, the large switching ripple in the modulation signal necessitates adjustment of the representation of the gain of the pulse-width modulator, which is dependent on the controller. Despite being highly accurate for stability assessment, the extended-frequency-range model is relatively complex after incorporating the effects of the sideband components and the large switching ripple. An approximate approach is introduced to simplify the loop gain expression and to provide physical insights into the effects of the sideband components and large modulation ripple amplitude. Experimental verification of the extended-frequency-range model is provided for a buck converter and a boost converter.
AB - Application of pulse width modulation (PWM) is known to produce sideband effects. The accuracy of the models of dc-dc converters can be improved if essential information of the sideband effects of PWM can be incorporated. In this paper, the aliasing effect of the sideband components on the closed-loop control is analyzed, and an effective representation of the transfer function of the pulse-width modulator is derived. Applying this transfer function to the dc-dc converter, an extended-frequency-range small-signal model is obtained, which can be conveniently used for deriving the loop gain of a PWM-controlled dc-dc converter. Furthermore, for wideband control applications, the large switching ripple in the modulation signal necessitates adjustment of the representation of the gain of the pulse-width modulator, which is dependent on the controller. Despite being highly accurate for stability assessment, the extended-frequency-range model is relatively complex after incorporating the effects of the sideband components and the large switching ripple. An approximate approach is introduced to simplify the loop gain expression and to provide physical insights into the effects of the sideband components and large modulation ripple amplitude. Experimental verification of the extended-frequency-range model is provided for a buck converter and a boost converter.
KW - Extended-frequency-range model
KW - large modulation signal
KW - pulse width modulation (PWM)
KW - sideband component
UR - http://www.scopus.com/inward/record.url?scp=85049393361&partnerID=8YFLogxK
U2 - 10.1109/TPEL.2017.2773641
DO - 10.1109/TPEL.2017.2773641
M3 - Journal article
AN - SCOPUS:85049393361
SN - 0885-8993
VL - 33
SP - 8151
EP - 8163
JO - IEEE Transactions on Power Electronics
JF - IEEE Transactions on Power Electronics
IS - 9
ER -