Press releases | 2022/09/15

Electrification and lower emissions: Exhibits of Liebherr at InnoTrans

New air-free brake actuator based on "brake-by-wire" principle
Liebherr Controlled Axle Steering "LiCAS" system reduces wear of rails and wheels
Demonstrator of a propane-based air-conditioning system
Powerful turbo compressor for fuel cell drives

As a highlight exhibit, Liebherr will present an air-free brake actuator for the first time at InnoTrans 2022 in Berlin. The actuator is part of Siemens Mobility's air-free brake system. Liebherr is also exhibiting other technologies and systems for rail vehicles - including a system for positioning wheelsets, a technology demonstrator for propane-based air-conditioning systems and a turbo compressor for fuel cell propulsion.

At InnoTrans 2022, Liebherr will be unveiling for the first time a new development for rail vehicle brake operations: The Siemens Mobility air-free brake system and its essential component, the air-free brake actuator. Liebherr and Siemens Mobility jointly developed the electro-hydraulic brake actuator that provides the brake force for the brake system.

Air-free brake actuator with "brake-by-wire" ready for series production

In contrast to a conventional pneumatic brake, the brake control in the new air-free brake system from Siemens is completely electrical. This system, also known as "brake-by-wire," therefore eliminates the need for all piping and all pneumatic components for controlling the brake. Siemens Mobility is using the new brake technology for the first time in the "X-Wagen" metro project in Vienna (Austria). There, it will go into passenger service at the end of 2022. In operation, the new system leads to lower costs in several areas: in maintenance, for example, and it also reduces the time required for train commissioning as well as cycle time.

153 years after development of the Westinghouse air brake, there is a real alternative available, which is ready for serial application. This innovation impresses with its decentralized architecture, compact design and various braking modes in one unit. Piping, compressors, and valve panels are no longer required for braking and can therefore be omitted entirely. Only a 24 V power supply and a CAN interface are used to control the brake actuator. Electronics and software are integrated in the actuator and were developed by Liebherr according to the highest safety requirements (SIL4).

Less wear on rails: Liebherr’s controlled axle steering

In addition to the innovation for braking technology, Liebherr is also showing its pioneering solution for active wheelset control. The active wheelset steering system "LiCAS" (Liebherr Controlled Axle Steering) significantly reduces wear on rails and wheels. LiCAS thus contributes to the longevity of rail infrastructure and the conservation of resources.

The system was developed by Liebherr-Transportation Systems and successfully subjected to an initial field test in cooperation with the British railroad company Grand Central (part of the Arriva Group) and NewRail (the center for rail transport research at Newcastle University).

Air-conditioning system with natural refrigerant propane

Liebherr-Transportation Systems is committed to making sustainable air-conditioning systems using natural refrigerants available to the global rail market. In addition to the existing technologies with the refrigerants R729 (air) or R744 (CO2), the company is currently focusing on solutions with R290 (propane).

Liebherr will be presenting a demonstrator for this purpose at the trade show. The corresponding technical concept, which takes into account all relevant safety requirements, was developed in cooperation with TÜV Süd. It is being implemented and verified on an existing passenger compartment air-conditioning system. A first series production-ready version will be available for the market from mid-2023.

Turbo compressor for fuel cells in rail traffic

Liebherr is also further expanding its expertise in solutions for zero-emission transport. Through cooperations with major car, truck and bus manufacturers, the range of electrically powered turbo compressors is growing. These can be used not only in maritime applications, long-distance buses, trucks and off-road vehicles, but also in fuel cells on board rail vehicles. The current versions cover the 25 kW, 35 kW and 55 kW power ranges.

The compressors and power electronics are designed, developed and produced by Liebherr: The two competence centers – Liebherr-Aerospace Toulouse (France), the specialist for air and thermal management systems, and Liebherr-Elektronik GmbH (Germany), the specialist for controls and power electronics – have joined forces for this purpose. The first series production of electric compressors is planned for the end of 2022.