Marelli launches new fuel system for hydrogen propulsion systems

Marelli has announced and launched its first hydrogen fuel system, including specific injectors with patented design and an advanced Engine Control Unit.

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. As per Marelli, its expertise in the high-pressure direct injection technology has the new fuel system meet the strict requirements of these engines, ensuring precision, efficiency, performance, easy integration and complexity reduction.

The whole functioning is controlled by an advanced Engine Control Unit.

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, as the unique player in the world to have developed and produced a 700+ bar gasoline direct injection (GDI) system, 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.

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.

Easy for OEMs to integrate into existing platforms

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. Moreover, 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.

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.