Automotive Design
One of the objectives is ensuring that Ferrari will be in a position to comply with future CO2
emissions standards,
particularly in terms of the urban cycle. City driving is traditionally where sports cars perform badly in terms of emissions, as their engines are designed for maximum efficiency and performance at high speeds. Despite its hybrid technology, the Hy-Kers car’s weight
distribution remains unchanged because the flat lithium-ion batteries are located below the floorpan of the car. Indeed, the car actually benefits from a lower centre of gravity, and interior and luggage space are unaffected. Maranello’s engineers also employed Ferrari’s track
experience in the design, engineering and manufacture of the innovative electric motor that produces over 100HP (Ferrari’s goal was to offset every kilogramme increase in weight by raising overall power output by 1HP). In operation, the motor cuts in during acceleration to give an instantaneous torque boost, with torque control being a function of grip, gear and accelerator pedal position. Depending on the vehicle speed and engine load – for example, in town driving – the hybrid system can function as a fully-electric drive train. Weighing about 40 kg, the compact, three-phase, high-
voltage electric motor is coupled to the rear of the dual- clutch, seven-speed F1 transmission. It operates through one of the transmission’s two clutches and engages one of the two gearbox primary shafts. Under braking, the electric drive unit acts as a generator to
recharge the batteries. This phase is controlled by a dedicated electronics module that was developed using the knowledge gained in F1 and, as well as managing the power supply and recharging the batteries, the module also powers the engine’s ancillaries via a generator mounted on the V12 engine.
Porsche trio
Also shown at Geneva was the Porsche 918 Spyder concept car, alongside the company’s new Cayenne S Hybrid production car and the 911 GT3 R Hybrid race car. Moreover, since the Geneva unveiling, the Supervisory Board of Porsche has agreed to series development of the 918 Spyder in Weissach (Fig. 2). The Concept Study of the 918 Spyder indicates that CO2
Fig. 2. Unveiled at the Geneva motor show as a concept car, the Porsche 918 Spyder is now due to be manufactured in small volumes.
the car’s kinetic energy into electrical energy to recharge the battery.
Inside, the driver is presented with three dials for road speed, engine speed and energy management. More striking, however, is the centre console that houses a touch-sensitive surface for control of the car’s functions, serving to reduce the number of visible controls and maintain the principle of direct operation (Fig. 3). A button on the steering wheel enables the driver to select from four different running modes, ranging from E-Drive mode in which the car uses electric power alone, though Race Hybrid mode in which the drive systems are focused on performance. There is also a push-to- pass button that provides additional torque from the electric drive system for faster acceleration, referred to by Porsche as E-boosting.
emissions will be just 70g/km, with
fuel consumption being of 3.0 litres per 100 km (94.1mpg) on the NEDC (New European Driving Cycle), yet acceleration from 0-100km/h (62mph) takes just under 3.2 seconds and the top speed is more than 320km/h (198 mph). Porsche says its 918 Spyder combines Porsche Intelligent
Performance technology, knowledge gained through motorsport, and classic but modern design. The open two- seater is powered by a high-speed V8 developing more than 500BHP; in addition, electric motors on the front and rear axles deliver a further 218BHP (160kW). The V8 engine is positioned in front of the rear axle, with power transmitted to the wheels by a seven-speed, double-clutch transmission that also feeds power from the electric drive system to the rear axle. Electric drive is transmitted to the front wheels via a fixed transmission ratio. Electrical energy is storied in a liquid-cooled lithium-ion
battery positioned behind the passenger cell. Being a ‘plug- in’ hybrid, the car’s battery can be charged from a regular electrical outlet. A regenerative braking system also converts
Fig. 3. The Porsche 918 Spyder’s centre console houses a touch-sensitive surface for controlling the car’s functions, while other controls are mounted on the steering wheel.
While the 918 Spyder is only due to be manufactured in small numbers, the Cayenne S Hybrid is a production car with a sophisticated parallel full hybrid drive-train that is said to combine the sporting performance of an eight-cylinder engine with the economy of a six-cylinder and a new ‘sailing mode’ for even lower fuel consumption. The Cayenne also features
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