INTEGERATED CONTROL STRATEGIES FOR CUK CONVERTER

Abstract

This thesis explores the design, analysis, modeling, and control of DC-DC converters, which are essential components in contemporary electronic systems valued for their efficiency, compactness, and reliability. With their wide range of uses in various industries like computer power supplies, aerospace, medical, and telecommunications, it is crucial for these converters to deliver a stable DC output voltage even in the face of fluctuating input voltage and varying load currents. Within the parameters of this study, particular focus is made to the Cuk converter in both ideal and non-ideal forms. Starting with important design issues, the paper improves the duty cycle, inductor, and capacitor calculations by including actual non-ideal factors. Especially in the performance of capacitors, a thorough study of output voltage ripple emphasizes even more the importance of the equivalent series resistances (ESRs). The thesis discusses the development of a comprehensive mathematical model that encompasses all aspects of the converter, including both ideal and non-ideal elements. Through the utilization of advanced techniques like state-space averaging and averaged switch modeling, a highly accurate model is created that closely resembles the dynamic and steady-state characteristics of real converters. Comparative study of the ideal model and the one with non-ideal components confirms the better accuracy of the latter, more precisely reflecting what practitioners could expect from real-world operations of DC-DC converters. This work investigates improving the performance of both ideal and non-ideal Cuk converters by means of several control techniques including sliding mode controllers, PI lead controllers, and PI controllers in the final part. Furthermore, it evaluates the sliding mode controller’s performance against the conventional two-loop PI controller configuration, therefore providing insightful analysis on how to maximize converter efficiency using sophisticated control techniques. All things considered, this study holistically covers the essential characteristics of DC-DC converters and provides important new perspectives on their optimization achieved with creative control strategies. The result opens the path for improved performance in electronic systems where such converters are essentially supporting.