German transmission supplier ZF has just started building production samples of a new electric motor that will be part of Mercedes-Benz new mild hybrid system. Mercedes co-developed the system with BMW and displayed it in several different vehicles shown at last fall's Frankfurt Motor Show. The first production application is expected to be the S400 hybrid which will pair a 3.5L gasoline V-6 with the 15kW electric motor/generator and a lithium ion battery to recapture energy from regenerative braking.
The motors are being manufactured by ZF's Sachs division at a plant in Schweinfurt Germany. ZF claims to be the first company to manufacture hybrid modules in Europe. Full production starts this fall at the rate of 35,000 annually and will eventually be ramped up to 200,000 a year. The Mercedes-BMW mild hybrid sandwiches the motor/generator between the engine and transmission to provide some low speed electric drive, electric power boost at higher speeds, auto start-stop and regenerative energy recapture. ZF currently has eight hybrid development projects with four manufacturers including Mercedes with production launches scheduled over the next four years.
[Source: ZF Friedrichshafen AG]
ZF Inaugurates New Production Location for Electric Drives
ï§ First-time volume production of hybrid modules in Europe.
* Start of production at the Schweinfurt location in the fourth quarter of 2008.
* First volume production order for Mercedes-Benz S-Class.
* Hybrid modules for cars, buses, and delivery vehicles.
On May 07, 2008, ZF's CEO Hans-Georg Härter and the Federal Minister of Economics and Technology, Michael Glos, officially inaugurated Germany's first production location for the industrial production of hybrid drive modules. Currently, release samples are being produced in a new production hall at the ZF Sachs location in Schweinfurt. From the fourth quarter of 2008, ZF will launch volume production and supply the products to car, bus, and delivery vehicle manufacturers. Mercedes-Benz will be the first customer. Thus, ZF is the first European automotive suppler to produce hybrid modules in volume production.
From the fourth quarter of 2008, hybrid modules with the product name DynaStart will be produced in volume production on a production surface of 1,200 square meters and shipped to customers. Currently, there are eight volume production development projects for four vehicle manufacturers; production will be launched between 2008 and 2012. To begin with, ZF is launching an annual production volume of altogether 35,000 units. The production volume in the now inaugurated hall can be extended flexibly up to a maximum of 200,000 units per year, which are then produced by approximately 50 employees.
"We are convinced that hybrid technology will gain ground in the years to come because it not only protects the environment but also pays off for the motorists", said ZF Chief Executive Officer, Mr. Hans-Georg Härter, at the inauguration ceremony. The Federal Minister of Economics, Michael Glos, honored the significance of hybrid technology as the industry of the future which can make an essential contribution to the necessary CO2 reduction. According to him, it is positive that - with a mature product - a German technological company assumes an important position in this market of the future. In 2008 alone, the ZF Group will invest more than €58 million in the development of hybrid technology.
Savings of up to 30 percent
The electric motors which are produced by ZF Sachs, the Powertrain and Suspension Components division of ZF Friedrichshafen AG, in Schweinfurt were developed especially for the integration into the driveline and are ideally suited for parallel hybrid drives. This concept allows for 30 percent fuel savings and emission reductions, depending on whether the vehicle is equipped with a mild hybrid or a full hybrid system.
These savings are based on the traditional hybrid functionalities, which can be implemented with the DynaStart by ZF Sachs: With the start/stop function, the combustion engine switches off during standstill, the electric motor lets the vehicle start, and the combustion engine is not activated before the optimal engine speed is attained. The electric motor is also capable of braking down the vehicle; in this process, it acts as a generator and transforms kinetic energy into electric power which can be stored in the battery ("recuperation"). Moreover, the high-torque module supports the combustion engine during acceleration by taking the energy from the intermediate storage, meaning that driving pleasure does not come off badly ("boosting").
With the parallel hybrid – contrary to the more complex concepts of series and power-split hybrids – only one electric motor feeds power into the driveline and this is done in parallel to the combustion engine, so the engine can be designed smaller with the same savings potential which is more favorable for the overall system.
High power-to-weight ratio and vibration damping
Depending on the application and customer requirements, ZF can produce hybrid modules at the new production location, featuring capacities between 10 and 100 kW and a maximum torque of 100 to 1000 Nm. In the mild hybrid version, the DynaStart allows for start/stop operation as well as recuperation.
As the two electric motors are installed on the crankshaft or transmission input shaft, between the engine and the transmission, know-how in terms of vibration damping was essential for the development of the DynaStart. The hybrid module is adapted to existing installation space conditions and the vibration and lurch movements as they occur in the drivelines of diesel and gasoline engines. As a manufacturer of torque converters and dual-mass flywheels, ZF Sachs has decades of experience and high innovative power with damping of torsional vibrations in the driveline.
In addition to international manufacturers, also other ZF Group divisions will draw back on the core component from Schweinfurt in order to offer passenger car and commercial vehicle transmissions with hybrid technology.
1.) Production launch: From the fourth quarter of 2008, volume production of hybrid modules will start in the new production hall for electric drives at ZF Sachs. Mercedes-Benz will be the first customer.
2.) Pioneer: Europe-wide, ZF is the first supplier to produce hybrid modules in volume production. The electric motors developed for use in the driveline feature a capacity of 10 to 100kW, depending on the application and customer request.