Closed-Loop Performance Evaluation of Boost, Cuk and SEPIC DC–DC Converters Using Simulation-Based Analysis

In this paper, three popular non-isolated DC-DC converter topologies—Boost, Cuk and SEPIC, converters are thoroughly modelled, mathematically derived, and their closed-loop performance compared. In contrast to traditional simulation-only studies, this work uses the principles of capacitor charge balance and inductor volt-second balance to derive the steady-state voltage conversion ratios. State space averaging and small-signal modelling are then used for control design. LTspice is used and assessed in the presence of load and input disruptions. To ensure a fair comparison, the converters are designed under identical operating conditions. Transient response, stability, ripple behaviour, efficiency trends, and robustness are used to evaluate performance. The findings show that regulation performance is greatly improved by closed-loop control, with simulation showing better disturbance rejection and less overshoot. The article offers design-focused recommendations for controller selection and topology in contemporary power electronic applications.