Parasitics Realization in State-Space Average-Value Modeling of PWM DC–DC Converters Using an Equal Area Method

Abstract

Average-value modeling of pulsewidth-modulation dc-dc converters is often based on the assumption of piecewise-linear waveforms of the circuit variables, whereas considering parasitics introduces waveform nonlinearity and complicates the model derivation. This paper presents a new approach that considers averaging with nonlinear waveforms using the equivalent area method, and proposes a state-space averaged model that is fairly accurate and seamlessly functional in both continuous and discontinuous conduction modes. The resulting average-value model is applicable for large-signal transient studies as well as for linearization and subsequent small-signal analysis. The proposed model is validated with a hardware prototype and a detailed simulation, and is shown to be an improvement over previously established models in the time and frequency domains.