Modeling and Simulation of Non-ideal Buck Converter in DCM

The modeling method is exemplified by Buckconverter operating in the discontinuous conduction mode(DCM), taking into account all parasitic resistances, thresholdvoltage of diode and inductor current ripples existing in actualconverters. Based on the theory of switch average model, timeaverage method of equivalent circuit, the theory of energyconservation, a circuit averaging method is studied to modelnon-ideal Buck converters operating in DCM, and a duty ratioconstraint which leads to a full order model is introduced. Onthe basis of DC circuit model and large and small-signalequivalent circuit model, the modeling and simulation analysisof non-ideal Buck converters are presented. Therefore, thederived models are convenient for modeling and designing ofDC-DC converter and its control system.