Bosch working on hydraulic hybrid for passenger cars

Alternative powertrain concept planned

Cost-effective way of reducing CO2 and consumption

  • Continuation of engineering collaboration with PSA Peugeot Citroën
  • Possible fuel saving of up to 45 percent in urban traffic
  • Robust and service-friendly technology

31-1-2013 — / — Following the successful introduction of the Bosch electric axle-split hybrid in PSA Peugeot Citroën diesel vehicles, the two companies are now planning to jointly develop a hydraulic hybrid powertrain for passenger cars. The hydraulic system basically comprises two hydraulic units and their pressure accumulators. The power-split concept allows the vehicle to be driven in three ways: the conventional mechanical way, hydraulically, or by a combination of the two. At low loads, therefore, the internal-combustion engine can be run at a more economical operating status. When braking, moreover, the kinetic energy that would otherwise be lost as heat is converted into hydraulic energy and stored in a pressure accumulator. This energy can then be used to drive the car. In addition, driving off can be done purely hydraulically, and short distances driven without any emissions. The result is a potential average CO2 reduction of 30 percent in the new European driving cycle, and as much as 45 percent in a purely urban driving cycle.

Cost-effective hybrid powertrain for compact cars
In principle, this technology can be combined with any conventional engine. In an initial phase, it is to be used in the compact car segment, but it is also suitable for other passenger-car segments and light delivery trucks in urban traffic. This hydraulic-mechanical powertrain system results in a hybrid powertrain that is more cost-effective, robust, and service-friendly. In addition, it does not require any special infrastructure, and can be deployed anywhere in the world.

Combination of Bosch expertise in automotive technology and industrial hydraulics
The technology works on the same hydraulic powertrain principles as those used worldwide on a wide scale by the Bosch Rexroth. Bosch and PSA see great potential for adapting this technology to passenger cars.

The close collaboration between PSA Peugeot Citroën and Bosch dates back to an engineering alliance set up in 2008. In the context of this strategic partnership, Peugeot launched the 3008 HYbrid4 in 2011, the world’s first series-produced diesel hybrid passenger car with an axle-split powertrain. In close collaboration with Bosch, PSA Peugoet Citroën developed the electrical components (electric motor, power electronics, and high-voltage generator) as well as the special technical design of the ESP® electronic stability program required for hybrid vehicles. This powertrain concept now also features in PSA’s Peugeot 508 (both the RXH station wagon and the HYbrid4 sedan) and Citroen DS5 HYbrid4 models. For these models as well, Bosch supplies the components for the electrical powertrain.

Automotive Technology is the largest Bosch Group business sector. According to preliminary figures, its sales came to 30.9 billion euros, or 59 percent of total group sales, in fiscal 2012. This makes the Bosch Group one of the leading automotive suppliers. Worldwide, some 171,000 Automotive Technology associates work in seven areas of business: injection technology for internal-combustion engines, powertrain peripherals, alternative drive concepts, active and passive safety systems, assistance and comfort functions, in-car information and communication, as well as services and technology for the automotive aftermarket. Bosch has been responsible for important automotive innovations, such as electronic engine management, the ESP® anti-skid system, and common-rail diesel technology.

The Bosch Group is a leading global supplier of technology and services, active in the fields of automotive technology, energy and building technology, industrial technology, and consumer goods. According to preliminary figures, more than 306,000 associates generated sales of 52.3 billion euros in 2012. The Bosch Group comprises Robert Bosch GmbH and its more than 350 subsidiaries and regional companies in some 60 countries. If its sales and service partners are included, then Bosch is represented in roughly 150 countries. This worldwide development, manufacturing, and sales network is the foundation for further growth. Bosch spent some 4.5 billion euros for research and development in 2012, and applied for over 4,700 patents worldwide. The Bosch Group’s products and services are designed to fascinate, and to improve the quality of life by providing solutions which are both innovative and beneficial. In this way, the company offers technology worldwide that is “Invented for life.”

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