Comparative analysis of nonlinear controllers applied to a bidirectional buck/boost DC–DC converter

Abstract

Buck/Boost converters require robust control to handle nonlinearities and uncertainties. However, conventional sliding mode control (CSMC) and backstepping control (BSC) methods suffer from chattering, tedious tuning, and unresolved tradeoffs between rapid response and steady-state stability. To address these issues, we propose a backstepping double integral sliding mode control (BDISMC) strategy optimized via Particle Swarm Optimization (PSO). A hyperbolic tangent function replaces the signum term to suppress chattering and enhance smoothness within a Lyapunov-stable framework. When benchmarked against SMC, BSC, integral sliding mode control (ISMC), and double integral sliding mode control (DISMC), our approach significantly improves settling and rising times, boosting responsiveness and robustness. Minor overshoot and undershoot occur during transients. Overall, this research provides valuable insights into converter control and clearly illustrates the intrinsic performance trade-offs among speed, stability, and precision.