Synergistic Dung Beetle MPPT and hippo-tuned PID control for hybrid FCEVs with CO 2 emissions mitigation

This paper presents an intelligent energy management and control framework for a Fuel Cell–Battery–Supercapacitor (FC–B–SC) Hybrid Electric Vehicle (FHEV) driving a Brushless DC (BLDC) motor through a regulated 450 V DC bus. The proposed approach combines a Hippopotamus Optimization (HO)-based PID controller for BLDC speed regulation and a Dung Beetle Optimization (DBO)-based Maximum Power Point Tracking (MPPT) strategy for Proton Exchange Membrane Fuel Cell (PEMFC) power extraction. Simulation results demonstrate that the HO-PID controller significantly improves the dynamic performance of the BLDC motor, achieving a settling time of 0.0979 s and an Integral of Squared Error (ISE) of 1470.01. Compared with the conventional PID controller, the proposed method reduces the settling time by 96.7% and the tracking error by 71.1%, while outperforming PSO-PID and GWO-PID controllers in terms of overall tracking accuracy. For fuel cell power optimization, the proposed DBO-MPPT algorithm was evaluated under six temperature scenarios ranging from 25°C to 82°C. The obtained results show that DBO consistently extracts higher power, providing approximately 700 W, 1.2 kW, and 3.5 kW more output power than PSO-MPPT, GWO-MPPT, and P&O methods, respectively, while maintaining steady-state oscillations below 0.5 kW. In contrast, the Incremental Conductance algorithm exhibited poor performance under nonlinear thermal operating conditions. Furthermore, the proposed hierarchical Energy Management System (EMS) ensures effective power sharing among the fuel cell, battery, and supercapacitor, maintaining DC bus voltage stability under dynamic load variations. Environmental analysis indicates zero direct tailpipe CO 2 emissions, with a total indirect CO 2 footprint of only 0.4329 kg, including 0.0181 kg from hydrogen production and 0.4148 kg from battery charging. The obtained results confirm that the synergistic integration of DBO-MPPT and HO-PID substantially enhances power extraction capability, speed tracking performance, system robustness, and environmental sustainability, making the proposed architecture a promising solution for next-generation low-carbon hybrid electric vehicles.