Robust Energy Management of Battery-Supported Hybrid Fuel Cell EV with Variable-Exponent SMC

This paper presents a robust control strategy for energy management in the hybrid power system (HPS) of a fuel cell electric vehicle (FCEV), where a fuel cell (FC) serves as the primary source supported by an ultra-capacitor (UC) and a lithium-ion battery. A DC-DC boost converter is used to link the fuel cell to the DC-link, whereas the UC and battery are integrated through bi-directional converters. The complete system is formulated as a fourth-order ordinary differential equation to accurately represent its dynamic behavior and incorporate model uncertainties. To address these challenges, a variable exponent-based non-singular integral sliding mode control scheme is proposed for coordinated energy management and DC-link voltage regulation. The controller guarantees fixed-time convergence of the closed-loop system, independent of initial conditions, while mitigating the effects of uncertainties. Numerical simulations validate the effectiveness of the proposed approach in ensuring robust, fast, and reliable performance to meet load demands.