Disturbance and Uncertainty-Immune Onboard Charging Batteries With Fuel Cell by Using Equivalent Load Fuzzy Logic Estimation-Based Backstepping Sliding-Mode Control

Proton exchange membrane fuel cell (PEMFC)/battery hybrid electric vehicle is considered as promising transportation due to its eco-friendly characteristics. This article investigates a fuzzy logic (FL)-based adaptive backstepping sliding-mode control (BSMC) approach to generate stable charging current and voltage for battery charging applications on a non-plug-in PEMFC vehicle. An adaptive BSMC is proposed to address nonlinearities and disturbances caused by dc/dc buck converter, PEMFC, and equivalent load variations of batteries. Moreover, an FL-based approximation is utilized to estimate the time-varying equivalent load of batteries through the adaptive laws obtained by the defined Lyapunov function and can offer assistance estimating the state of charge (SOC) of batteries. Simulation comparisons between a proportional-integral (PI) control and the proposed FL-based adaptive BSMC were executed subsequently under certain conditions to validate the efficacy. Finally, experiments on the PEMFC/battery hybrid power system scaling prototype via NI (PCI-6229)-LabVIEW platform were implemented to test the charging performance of the proposed approach. The comparative results indicated that the FL-based adaptive BSMC method could regulate charging current and voltage against disturbance and uncertainty and estimate the equivalent load of batteries accurately.