Averaged Discrete-Time Model for Fast Simulation of PWM Converters in DCM

Abstract

Continuous and discrete-time averaged models are available for pulse width modulated (PWM) converters operating in the continuous conduction mode (CCM). A new discrete-time model for PWM converters operating in the discontinuous conduction mode (DCM) is proposed that leads to the exact discrete-time mathematical representation of the averaged values of the output signal.This model can also provide the averaged values of other internal signals with little increase in simulation time. This model is also used to simulate PWM converters operating in both DCM and CCM when combined with the averaged CCM model in [1]. It is compared to other models with respect to accuracy and simulation speed through a numerical example of boost converter. This method gives the exact values of the one-cycle-average (OCA) values of signals at switching instants. Numerical simulations show the accuracy and speed of the proposed method as well as its advantage in simulating PWM converters operating in both CCM and DCM.