Hybrid PI and Sliding Mode Control for Non‐Inverting Buck–Boost Converters With Experimental Validation

ABSTRACT This paper presents a hybrid control strategy for a non‐inverting Buck–Boost DC–DC converter used in photovoltaic energy management. The converter employs two independent Buck and Boost stages, enabling decoupled control loops and fast tracking of rapidly varying reference signals. A combined PI–SMC framework is proposed, where the outer loop regulates the output voltage using a PI controller, and the inner loop controls the inductor current via a smooth Sliding Mode Control (SMC) law based on an arctan(s) switching function. This smooth SMC formulation effectively reduces chattering and high‐frequency oscillations while improving tracking accuracy and robustness. Simulation results show short settling time, fast recovery under abrupt input and load variations, and stable performance across the full Buck–Boost operating range. Quantitative NRMSE (Normalized Root Mean Square Error) analysis confirms high tracking quality, with the output voltage exceeding 90% and the inductor current reaching about 98%. Experimental implementation on a TMS320F28379 DSP further validates the proposed method. The results demonstrate improved disturbance rejection and reduced sensitivity to parameter uncertainties, making the approach well suited for practical renewable‐energy power converters.