A multi-method control strategy for numerically testing a fuel cell-battery-supercapacitor tramway

A fuel cell-battery-supercapacitor powertrain, for railways, is investigated and numerically modelled. Each main powertrain component, such as energy sources, power electronic and drivetrain components, is analysed in detail; electrochemical, logic and physic equations are used to design the models, formalizing and implementing them in Matlab-Simulink. To achieve a proper behaviour and high performance, two control strategies are implemented: an ad-hoc power-sharing system, designed for railways, that connects principles of global drive-cycle knowledge and real-time methods; a motor control, composed of a proportional-integral speed and a direct torque control. Therefore, the controllers can take advantage of the powertrain component peculiarities, selecting a proper role for each energy source, and accurately manage the electric motor. The fuel cell-based powertrain is tested on a real urban route, offering a public service from/to the University of Calabria. The simulation results are investigated on different levels of details: a meticulous energy efficiency and performance analysis is conducted. The output power and hydrogen consumption (approximately 0.3 kg/km) are examined and losses and efficiencies of each component are evaluated, reaching 42.5% overall vehicle efficiency, in order to study the energy flux and form conclusive considerations regarding the pros and cons of fuel cell hybrid systems for railways.