Singular perturbations in integral control of DC-to-DC power converters

A novel approach to evaluate asymptotic stability of current-mode control for DC-DC power converters is given based on the singular perturbations (time-scale separation) approach. The small parameter ε which separates time scales is related to the physical values of inductances and capacitances through the LC matrix M = εS. Our approach also results in asymptotic stability of a simple robust integral output controller for a large class of PWM DC-DC power converters, which is robust to variations in the voltage source E and load Ro. Some remarks are given at the end about performance limitations of this controller and how to improve the closed-loop converter behavior including LC parameters as part of the controller design.