Average Current-Mode Control for a Quadratic Buck Converter

In this paper, a methodology for controller design of a quadratic buck converter is given using average current-mode control. This scheme employs an inner loop that uses the average current of the first inductor and an outer loop that senses the output voltage for feedback purposes. Thus, a procedure is developed for the proper selection of: (a) the current gain for the inner loop, and (b) PI-controller for the outer loop. The design-oriented analytic results allow the designer to easily pinpoint the control circuit parameters that optimize the converter´s performance. At the end, experimental results are given for a 28 W current-programmed regulator