Unified Control Strategy for Step-Up DC–DC Converters With User-Defined Robustness
Purnima Verma, Md Nishat Anwar, G. Lloyds Raja
Abstract
This paper presents a unified controller design technique for managing the output voltage in various types of step-up DC-DC converters with non-minimum phase dynamics. The proposed methodology entails selecting a desired reference model and equating the closed-loop transfer function with it at a low frequency point. Thus, the integral and derivative gains of the proportional-integral-derivative controller are expressed in terms of its proportional gain. The proportional gain is chosen based on a robustness measure specified by the user (maximum sensitivity). Although this unified approach is applicable to a wide range of step-up DC-DC converters, the current study demonstrates it using benchmark boost and quadratic boost converters. Experimentally, rigorous comparative evaluations are performed on certain published controller designs (working in both current and voltage control modes) to support the effectiveness of the control approach in many practical scenarios. Furthermore, the suggested technique can function amid parametric uncertainties and even in discontinuous conduction mode.