Advanced MPPT and Voltage Regulation in PV-EL Stack Systems Using Backstepping Sliding Mode Control

Abstract

This paper presents a robust approach for maximum power point tracking (MPPT) and voltage regulation control in a Photovoltaic-Electrolyzer (PV-EL) stack under defined operational conditions. The system under study includes a PV module that supplies power to a PEM electrolyzer through a two-stage DC-DC converter system (boost and buck). The BSMC controller, introduced as a robust solution, incorporates the advantages of standard SMC and backstepping approaches. The Lyapunov function is employed to validate the stability of the controlled PV-EL stack system. The proposed BSMC controller is extensively simulated and benchmarked against conventional SMC under varying operating conditions. The simulation results clearly demonstrate that the suggested approach for MPPT and voltage regulation offers improved robustness against parameter uncertainties, faster transient responses, and superior tracking performance compared to conventional sliding mode control. Under varying operational conditions of the PEM electrolyzer, the system achieves a rapid response, settling within 0.065 seconds for MPPT and 0.55 seconds for voltage regulation without overshoot.