Large-signal average modeling of 2-module Converter for renewable energy applications

In this paper, a large-signal average model for a modular system is presented. The studied system is a two-module structure based on a three-level boost converter. This topology has been used to balance the dc output voltages in renewable systems. To establish the model, the equations of the system, including the stage power and the used indirect sliding-mode controller, are considered. The accuracy of the presented model is validated. To verify the accuracy of the large-signal model, the system is simulated using MATLAB/Simulink software. The simulation is performed using the large-signal averaged and switched models. The switched model is simulated in MATLAB/Simscape (Circuit-Oriented Simulation), whereas the averaged model is simulated in a MATLAB function. The accuracy of the averaged model by two simulations is compared in the transient regime for two scenarios. One in which the inductor current reference is changed and another in which the input voltage is changed.