Advanced control strategies for fuel cell hybrid electric vehicles — A review

Fuel cell (FC) technologies convert chemical energy from hydrogen and oxygen to generate electricity, producing water and oxygen gas as harmless by-products. This makes FC an attractive option for powering electric vehicles (EVs), significantly reducing carbon emissions from road transportation. However, the FC technologies for EV applications face several challenges, including limited fuel, low power density, and slow dynamic response during high load variations. Most of the time, these problems can be avoided by pairing the FC with other energy sources like flywheels, supercapacitors (SC), battery energy storage (BES), and so on. This configuration is called the fuel cell hybrid electric vehicle (FCHEV). The coordination among the various energy sources and the load on the FCHEV is facilitated by energy management strategies (EMSs) and control algorithms. The EMSs share the load demand among the energy sources according to their power characteristics. Meanwhile, the control algorithms ensure that the energy sources produce the required currents while stabilizing the DC bus voltage of the FCHEV. However, aging, external disturbances, faults, parametric variations, and load fluctuations of the FCHEV affect the effectiveness of the control algorithms. As such, several advanced control algorithms have been proposed to mitigate these problems, achieve accurate and reliable power performance, preserve the health of the powertrain components, maintain supply–demand balance, minimize fuel consumption, and extend the range of the FCHEV. This paper provides a comprehensive introduction and classification of the state-of-the-art literature survey on various control methods applied to FCHEV. In addition, the paper presents an overview of energy sources and fuel cell hybrid energy systems used for the FCHEV. This paper helps researchers gain insight into the past, recent progress, and future outlooks in the applied control methods in FCHEV.