Marelli is presenting its first hydrogen fuel system, including specific injectors with a patented design and an advanced Engine Control Unit, at the CTI Symposium in Germany at booth G12, Dec. 5-6, 2023.
CTI Symposium 2023 is one of the largest international industry events in Europe about sustainable automotive powertrain technologies for passenger cars and commercial vehicles, according to Marelli.
At the event, Marelli also will showcase other advanced technologies for different kind of propulsions to support the mobility of the future. The display will include the 1,000-bar GDI fuel system, the Vehicle Domain Control Module for vehicles with different powertrains, as well as the full range of wired and wireless Battery Management Systems and the multipurpose smart actuators for transmission and thermal management aimed at electric vehicles.
“This state-of-the-art solution is aimed at hydrogen engines, which are similar to traditional endothermic engines but use hydrogen as fuel, producing no CO2 emissions, thus representing an interesting option for eco-mobility. Based on the company’s expertise in the high-pressure direct injection technology, the new Marelli’s fuel system meets the strict requirements of these engines, ensuring precision, efficiency, performance, easy integration and complexity reduction,” the company said.
As hydrogen is a very light and reactive gas, a very precise fuel injection inside the combustion chamber is required, together with specific solutions to avoid pre-ignitions and backfire. It also needs a higher compression ratio than common gasoline engines to exploit the fuel efficiently. This makes the direct injection system a key enabler for this technology, Marelli said.
Marelli, which developed and produced a 700+ bar gasoline direct injection (GDI) system, said it has moved from its experience of the 1,000-bar system to develop, still in the Propulsion Solutions R&D center in Bologna, a solution “specifically suited for hydrogen, that guarantees high durability and injection stability, with excellent performance.”
Marelli said this allowed the company to develop reliable and low-noise direct injectors aimed for hydrogen, with the same dimensions as those used for traditional fuels, making it easier for carmakers to integrate them into existing platforms. In addition, these injectors feature a double actuation, a specific magnetic circuit to control the speed of the needle and a high static flow that can meet the requirements of a variety of different vehicles. The patented design also allows to overcome uncontrolled hits between the injector’s dynamic components, to reduce performance drifts. Finally, the use of a standard command control contributes to reducing system costs and complexity, according to Marelli.
The fuel system also includes a pressure reducer with an integrated regulator, to reduce hydrogen pressure to the injection’s working pressure, and a specific manifold, tested for the most severe automotive applications. The whole functioning is controlled by an advanced Engine Control Unit, featuring software algorithms and specific strategies developed in-house by Marelli to manage the more complex hydrogen-based system.
