Hybrid technology in passenger cars and light trucks 

+++Volkswagen steps up in hybrid plug-in-technology

At the Vienna Motor Symposium on May 6-7, 2011, the Chairman of the Volkswagen Group, Prof. Dr. Martin Winterkorn, announced that the Volkswagen Group will be going into production with a range of

important models with plug-in hybrid technology starting in 2013/14.

The electric car will impact the future of individual mobility in crucial ways – and Volkswagen

is spearheading this technology. Over the mid-term, the plug-in hybrid offers great potential,

because it combines the best of two worlds in one vehicle,” said Winterkorn. The plug-in

hybrid offers precisely what many customers expect: unlimited internal combustion engine

performance combined with attractive electric mobility ranges in everyday driving. Moreover,

Winterkorn noted that there are no limitations to the vehicle’s speed, climbing or towing

abilities. He also stated that plug-in technology has excellent potential for reducing CO2

emissions.

“Electric mobility is the task of the century for the automotive industry and the European

industrial community as a whole. Manufacturers, suppliers, energy providers, scientists and

politicians – everyone must step up to the plate here,” said the Volkswagen chairman.

Winterkorn spoke in support of more targeted research funding, especially in the field of

electro-chemistry for battery technology.+++www.volkswagen-com

Bosch Full-Hybrid-Car

New hybrid-concept by Bosch

The world-wide first parallel-full-crossbreeds with the hybrid-variations of the Volkswagen Touareg and Porsche Cayenne S are being built in series. Bosch developed the innovative hybrid-concept in close cooperation with the two car manufacturers. Advanced control-technology manages the interplay of combustion-motor and e-machine .

“An essential advantage of our system is its simple construction", says Oliver Schlesiger. The engineer works at a new interpretation of the hybrid-drive since 2007 as a customer-project-leader of Bosch. The customers, Volkswagen and Porsche. marketed the result in April 2010. The VW Touareg Hybrid and the Porsche Cayenne S Hybrid are the first "parallel-full-hybrids" worldwide. Bosch contributes the hybrid-drive-components.

It is not simple to find the way around in the tangle of the "parallel", "serial", "mild" and "full" hybrid. The hybrid-variations of the Volkswagen Touareg and Porsche Cayenne are full-hybrids, which,  in contrast to the mild hybrids, allow purely electric driving over short distances. The two manufacturers favor a parallel-hybrid-system of Bosch at  their common car-platform. Because. shortly said, intelligence replaces trivial mechanics here. This reduces costs and complexity. "Moreover, our e-Machine is practically autonomous. You can drive purely electrically anytime by opening the clutch, and turn off the combustion-engine”, Schlesiger explains.

Bosch developed hybrid drives already in the 70s. Since then, research and development in this area remained continuously. In the meantime, a team of 500 experts are developping  electric drives. Systematically, they optimize components like e-machines or power-electronics. And they take up new-developments of other Bosch-departments.  “We developed basic know-How  with  directly-injecting Fuel-motors, Schlesiger explains. He went his first steps in projects, from the first Motronic-units, followed by direct injection with Bosch.

Soft ride is the developers goal, when  the e-machine is cooperating with the combustion-motor. This happens automatically with the parallel-full-hybrids of Volkswagen and Porsche. “The wish of the driver for torque is the decisive factor”, says Dr. Matthias Küsell, leader of the hybrid-development of Bosch. In other words: the control can read the drivers intention  from his  gas-foot. Ever after, whether he/it accelerates moderately in the city-traffic, at free trip to the sprint begins, is fast on highway and country road on the way, or whether he/it would like to only "with-sail". The control translates the pressure on the accelerator into electric, hybrid or combustion-motor driving. Vice-versa she/it calculates on the basis of the brake pedal-way which brake-element should be put by the E-Machine. "Security-systems like ABS or ESP have priority", according  to Küsell, anyway.

A hybrid would be a rather nervous car,  if the transitions would be perceptible between the drives.  However how is the V6 of Cayenne and Touareg  synchronized exactly on few milli-seconds with the E-Machine by Bosch? How do the developers reach that softly 245 kilowatts (333 HPS) and up to 440 Newton-meters of torque of the direct-injection-engine with 34 kilowatts (47 HPS) and 300 Newton-meters of the E-Machine flow together? The solution is in the interplay of Sensors, control-technology and Actors.

 

 The E-machine is placed between the combustion-motor and the 8-step-automatic transmissions. The hybrid-module unites the integrated motor generator (IMG), with 30 centimeters of diameter on the 145 millimeters actuated clutch, a water-cooling and of course the permanent-magnets and spools of rotor and Stator. On top, the engineers  accommodated digital sensors in order to continuously control  the respective rotor-situation. The IMG can drive the car up to 60 km/h autonomously. At the sprint, it works together with the combustion engine and drives the parallel-hybrid into under 6,5 seconds of zero on 100 km/h. By this"Boosting", the performance rises by 279 kilowatts (380 HPS), and the driver can call up to 580 Newton-meters of torque. In quieter driving-situations and when braking, the IMG works as generator on the other hand and passes on the so generated stream to another kernel-element of the hybrid-vehicles: the accomplishment-electronics.

The performance-electronics are also delivered by Bosch. It is integrated in the water-cooling-cycle, because the appliance contains a high-performance Trafo  with ten liters of volume. Here, two things are happening. On the one hand, the appliance mediates between the 288 volt (370 amperes) - net of the hybrid-drive and the 12-volt-system of the vehicle. On the other hand, Bipolar-Transistors change the direct current of the battery in three-phase alternating current for the E-Machine and turned back.

The components are controlled by a hybrid-tuner-amplifier of Bosch. With their development, Küsell's team could build up on the Motronic  for the directly-injection. Know-how flowed in moreover from start-stop-systems. Prerequisite: Sensors constantly provide the control with data about temperatures, position of the pistons or the speed of the motor. "The corresponding protocols and interfaces are a result of the start-stop-technology",  Küsell explains.

Among other things, the Touareg Hybrid and Cayenne S Hybrid are burning just 8,2 liters of gas thanks to the parallel electric drive in the EC-cycle on 100 kilometers (193 grams CO2 per kilometer). The parallel-hybrid version the V8, compared with the vehicles first generation, uses up to 40 percent less fuel.

 

Technology in the detail: The Bosch-Components for the parallel Full-Hybrids  

The performance-electronics

Function:

Requires bandage-limb between battery, that stores direct current, and the E-Machine, the three-phase alternating current and generates. Shells the direct current counter an Inverter (pulse-change-judges) with help of Bipolar-Transistors. Moreover, a direct current-transformer (DC / DC) mediates - transformers between 12 volt-shelf-tissues of the total-vehicle and the 288 volt-tissue of the electric drive.

Challenge:

Keyword consumption: from initially 15 liters of prefabricated part-volume, 10 liters are remaining in the Cayenne and Touareg. Today, Bosch works on a 5 liter-solution.

Keyword lifecycle. it is necessary to try on the appliance in the vehicle (-40°C. 120°C) at the rough conditions and to guarantee his/its function over the entire car life away.

 Keyword efficiency. Necessary is cooling, but the ridge to the energy-waste is narrow. Temperature-sensors in the accomplishment-electronics guarantee that the cooling water-pump runs only with demand.

Keyword numbers of pieces. The construction must remain big-series-useful and modular. The components must let themselves adjust easily at existing spatial realities of different car-models.

Exciting detail:

Kernel-components are counters, that in a flash at - and relaxes, about the direct current to pulses. The burden of these counters. actually it is semiconductors. is enormous. Only over more chip-surfaces the performance lets itself increase. However the developers want the opposite. The Inverter should shrink instead of growing further. Keys to it: Coolness-concepts, new semiconductor-materials and new construction and connection-technology. Or also constructive skill. "The Inverter is extremely narrowly packed. If one would place a fly in, she/it probably would not find out again, Bosch expert Martin Millich explains.

 

The E-Machine (integrated motor generator, IMG))

Function:

The electric drive is a round "disk" of 30 centimeters of diameter, that sits between combustion-motor and mechanisms. It is a water-cooled, permanent-magnet-emotional synchronous-machine precisely with indoors current rotor. It starts the combustion-motor, allows electric driving purely, can be driven together with the combustion-motor and changes brake-energy or also torque of the  generator in stream.

Challenge:

Keyword design. High performance-density on little area requires refrigeration. Especially since the combustion-motor emits heat. Accordingly, coolness-canals pull through the outside lying Stator, that  leads away also the affecting heat from the indoors circling rotor. The distances of current-carrying between metallic sharing are minimal. The developers are in the split between minimum-distances and maximum accomplishment-density.

Keyword start. it is a challenge to head for the IMG with his/its start so, that the rotor immediately rotates into the correct direction. Three digital sensors oversee situation and speed of the rotor to it. Henceforth, the sensors could determine also the trick-direction of the motor. because in pure electro-vehicles, the mechanism slips. the control must know whether it goes onward or backwards.

The hybrid-control

Function:

The tuner-amplifier is the brain of the Parallel-Hybrids. Here, sensor-data from electric and combustion-motor drive-rope flow together. All this happens in real time and is basis for an efficient and comfortable interplay of combustion-motor and E-Engine. Central entrance-size is the driver-wish expressed per gas or brake pedal.

Exciting detail:

The Driver pretends, when and how the car goes electrically. Bosch offers such strategies, however many manufacturers want to shape in order to line up the driving-behavior of the hybrid at her/its/their philosophy themselves. An additional CAN-Bus guarantees that the hybrid-control can access all required sensor-data in real time.

Russian Onexim-group plans hybrid city-car

According to "Russia Today", the Russian industrial Group Onexim, owned by P.Prokhorow, Russias wealthiest oligarch, is planning a city-hybrid-car with a totally new concept: As a joint venture with Truck-Maker Yarovit from St.Petersburg, the Yo-Mobil called 4-Seater will be equipped with a gas-powered Generator directly charging an e-engine with an output of about 44 kW. With this CNG-concept, no gear-drive nor battery will be needed. The first three prototypes are powered by an old german Wagner-engine. www.onexim.ru

System comparison of hybrid-architectures (ZF)

There are three different hybrid-architectures: the parallel ones, the serial and the power distributed hybrid-drives. The parallel structure enables a wide degree of the hybridization on different vehicles. Besides the full hybrid, also micro and mild-hybrid-systems become possible.

Parallel hybrid-drive 

With the parallel hybrid-drive, the combustion-motor one and the electric drive are parallel switched. They can be used individually or together. The parallel hybrid is functioning only on an electric machine, which reduces costs. This delivers the advantage that existing mechanisms with its driving-dynamic advantages can be used. Particular know-how requires the system-integration. The technological leadership of the ZF Group ZF for the entire drive-chain pays off here. The parallel hybrid leaves itself as micro, mildly, and full hybrid train and can be integrated in passenger cars as well as in commercial vehicles.

Serial hybrid-drive  

With the serial hybrid-drive, there is not any mechanical connection between combustion-motor and wheels. The combustion-motor serves exclusively as generator in connection with a generator. The drive-performance flows from the generator over one or several electric machines to the drivetrain or directly to the wheels. This way, the combustion-engine can be run always run in the ideal economical range even if high speeds are required or when starting and accelerating. ZF offers an electro-portal-axis for serial hybrid-drives for buses.

Power-distributed hybrid-drive 

The power distributed hybrid-drive functions with two electric machines. A part of the drive-performance of the combustion-motor is being distributed to the energy cells, a second part is transferred mechanically. How the performance-shares are flowing in the system , depends on  the respective working conditions . A central tuner-amplifier is controlling the complicated technology. The combustion-motor can be driven in its ideal economical range at any time, and the electric machines can be smaller, space-saving by comparison to the serial one.