A CAD package for fast simulation of regulated dc-dc converters in large-signal

This paper presents a CAD package for fast simulation of regulated dc-dc converters. Operating under the MATLAB environment, the package can offer accurate dynamic responses of the closed-loop system even when large-signal disturbances are involved. Thanks to a proposed large-signal modeling approach of the switching circuit, and the capability of MATLAB on solving nonlinear differential equations efficiently, the difficulty in simulating the switching circuits can be overcome. The model for the whole topology and the control scheme closing the feedback loop can then be easily built. In this paper, the modeling of PWM switching circuit and zero-current-switch Quasi-resonant switching circuit will be discussed, and simulations of the four basic topologies will be presented. All of these features are realized through a user-friendly interface to the CAD package.