Abstract—Various aspects for the averaged modelling of the Boost converters operating in the discontinuous conduction mode (DCM) are studied. The parasitics of the Boost converter are also considered. A duty ratio constraint that defines the diode conduction interval is identified to be the key for accurate prediction of high-frequency behaviour. A new duty-ratio constraint is proposed that leads to the full-order averaged models of DCM converters. Numerical analyses and experimental measurements confirm that the new models correctly predict the small-signal responses up to the half of switching frequency and are more accurate than previous models. Moreover, the analytical results are included to show the origin of the high-frequency pole in DCM operation and to explain why the full-order model is capable of accurately predicting it.

Index Terms—Discontinuous Conduction Mode, Boost Converters, Duty Ratio Constraint

Gang-jun Xie is with School of Electronic Science and Applied Physics,Hefei University of Technology, Hefei 230009, Anhui, China(corresponding author, e-mail: gjxie8005@hfut.edu.cn).
Hai-bin Fang is with School of Electronic Science and Applied Physics,Hefei University of Technology, Hefei 230009, Anhui, China.
Xin Cheng is with School of Electronic Science and Applied Physics,Hefei University of Technology, Hefei 230009, Anhui, China.

Cite: Guang-jun Xie, Hai-bin Fang and Xin Cheng, "Non-ideal Models and Simulation of Boost Converters Operating in DCM," International Journal of Computer and Electrical Engineering vol. 2, no. 4, pp. 730-733, 2010.