Test environment for fuel cell-based drives up to 1.5 MW
Investigation of the individual core components (fuel cells, liquid hydrogen tank, battery and electric motor) and their interconnection in a ground-based test environment
Reducing greenhouse gas emissions in aviation is a challenging and largely unsolved task. Converting propulsion systems based on fuel cells, which convert the reaction energy of hydrogen and oxygen into electrical energy while emitting only water, is a promising way of avoiding greenhouse gas emissions. However, there is currently only one fuel cell-powered passenger aircraft with a propulsion power of 80 kW and four seats. In order to make regional aircraft with 40 to 60 seats and a range of 1,000 kilometres possible, a considerable upscaling of the existing components is required.
To demonstrate the upscaling to 1.5 MW, DLR is building a unique test environment with several industrial partners as part of the BALIS project (fuel cell-based powertrain for aircraft 1.5+ MW), which comprises the core components consisting of a fuel cell system, a tank for liquid hydrogen, a drive unit and a battery as well as the control and regulation technology including the associated infrastructure (see Figure 1). The components can be operated and tested both individually and in combination via a switching matrix. This makes it possible to simulate and analyse any load cases for an aircraft for each component and the overall system.
An exemplary load profile is shown in Figure 2. Here, the movement to the runway is first simulated at a low speed. During the subsequent take-off phase, the maximum system power is called up for 10 minutes. The aircraft then climbs to the desired cruising altitude within 20 minutes at a high power of 1.2 MW, which is then maintained for 60 minutes at medium power.
The test environment, funded by the Federal Ministry of Transport and Digital Infrastructure (BMVI) with 26 million euros, is being set up in several modular containers on the Empfingen Innovation Campus near Stuttgart. Coordinated by DLR, an industrial system partner is setting up the necessary measurement and testing infrastructure. The flight-relevant core components will be developed in collaboration with several technology partners and integrated into the test environment. Construction is scheduled to begin in October 2021 and the entire system will be demonstrated by the end of the project in June 2023.
