Peugeot 308 HybridHDi Demonstrator at Frankfurt

Press Release

The 308 HybridHDi - Maximising environmental efficiency

In its pearlescent white and green uniform, two colours chosen as symbols of purity and ecology, the 308 HybridHDi demonstrator is the eagerly anticipated star of the environmental section of Peugeot’s stand at the 2007 Frankfurt Motor Show.

For a number of years, protection of the environment has been an integral part of the PSA PEUGEOT CITROËN group’s development policy. This preoccupation is based on strong beliefs and has brought substantial results. Nowhere more so than in Europe, where in 2006 the Group sold one million vehicles emitting less than 140 g of CO2 per km and helped make the PSA Peugeot Citroën group one of the world’s leading manufacturers of vehicles with low greenhouse gas emissions.

Many technological innovations aimed at cutting fuel consumption and exhaust emissions are being introduced by Peugeot according to specific market requirements, all aimed at protecting the environment.

In the European market for example, where diesel sales have risen to become the most popular choice due to technological developments and the adoption of diesel particulate emission filter systems (DPFS). Diesel equipped vehicles are more economical and «cleaner» to run, however, further reductions in fuel consumption can be achieved by using hybrid technology coupled with a diesel engine. Based on like for like power, this technology offers a reduction in fuel consumption and CO2 emissions of around 35% compared to a traditional diesel engine.

Research is, however, still ongoing with a view to making this technology available to European consumers in the near future.

This new HybridHDi technological demonstrator which is showcased at the Frankfurt Motor Show represents another step on the path towards the planned commercialisation of the vehicle in 2010.

Reviews carried out since the unveiling of the first 307 HybridHDi demonstrator in 2006 have confirmed the sound judgment of the initial strategic and technical decisions. In the first place, the choice of the diesel engine in a parallel hybrid power train produces a significant reduction in fuel consumption, and secondly the introduction of this technology into family vehicles which form the basis of the European market.

The demonstrator presented is a 308 Premium Pack five door model incorporating the most efficient parallel hybrid architecture to date, combined with a 6-speed electronically controlled manual gearbox. The 80 kW 1.6 HDi DPFS diesel engine coupled with a 16 kW electric motor provides an available power of 96 kW, comparable to that of the 308 with the 2.0 litre HDi DPFS 100 kW diesel engine.

Fuel consumption in the combined cycle is 3.4 litres/100 km and 90g/km of CO2 or a reduction of 38 % compared to an equivalent 308 HDi.

In addition, the engine has been designed to meet the future Euro V directive which comes into force in 2009 and offers the possibility of driving exclusively in electric or “ZEV” (Zero Emission Vehicle) mode for journeys in regulated urban centres.

The aerodynamic specification of the 308 hatchback (SCx of 0.67 and Cx of 0.29) and the adoption of Michelin Energy Saver tyres with reduced rolling resistance further help to enhance the performance of this demonstrator.

A step towards commercialisation

Compared to the previous 307 HybridHDi concept car presented in 2006, the focus of research has shifted naturally to redeployment of the technology in the structure of the new 308 and to compatibility with the future Euro V directive.

The inclusion of the specific components required for the HybridHDi technology has taken into account the strict requirements of production vehicles, particularly the 308s high safety levels.

This new demonstrator offers technological advances in an arrangement similar to that of the production model, but with a more efficient power train providing extremely low levels of fuel consumption.

To obtain a favourable cost ratio, priority was been given to using components and units available on group models. The number of elements specific to hybridisation of the 308 has been reduced by around 30% compared to the previous 307 HybridHDi demonstrator. The selected suppliers of these components are all key partners in bringing this project to fruition.

A simple, automatic technology

Starting of the vehicle by means of the customary ignition key is free from any noise, since the diesel engine is not started. By pressing the accelerator pedal with the gearbox in automatic mode, the electric motor sets the vehicle in motion with an unprecedented level of comfort in terms of noise and vibration. The diesel engine is switched on and off by means of the stop and start system. Power train operating modes are controlled by the PTMU (Power Train Management Unit) according to instructions from the driver.

To inform the driver in real time of the exchange of energy flows, an operating schematic can be shown on the vehicle’s colour multifunction display (7″16/9).

Other information is also available, such as the battery charge status or the power train operation mode.

A well equipped vehicle without compromise in terms of specification

No sacrifice has been made in terms of the Marque’s central concerns of driving pleasure and equipment levels. This richly equipped demonstrator features the Premium Pack level of the 308 and includes a panoramic glass roof and the RT4 system with retractable display screen.

The level of comfort equipment in particular, and also its interior space, brightness, dynamic qualities and driveability, are no different to those of the standard 308.

General dynamic performance is comparable to the benchmark 308 HDi; however in-gear acceleration, both in town and on the open road, is improved with the HybridHDi. Indeed,

during in-gear acceleration, the diesel engine is backed up by the electric motor which is able on demand to deliver a power boost of up to 23 kW (and 130 Nm)

Confirmation and optimisation of HybridHDi technology

The parallel hybrid power train is made up of the 1.6 litre HDi DPFS 80 kW (110 bhp) diesel engine and an electric motor with a continuous output of 16 kW and a torque of 80Nm. The PTMU (Power Train Management Unit) selects the right distribution of power from both units to meet demand formulated by the driver in order to favour low fuel consumption.

Schematically, the electric motor alone is responsible for starting and driving at low speed, while only the diesel engine is used on open roads and motorways, with both units coming into play simultaneously to provide quicker acceleration.

This system is coupled with a 6-speed electronically controlled manual gearbox able to operate in automatic or manual mode with sequential gear changes.

Kinetic energy recovered during phases of deceleration and braking recharges the batteries via the “reversible” electric motor.

A special button provides access to an all-electric “ZEV” Zero Emission Vehicle mode. Actuation of the diesel engine is then restricted to more pronounced acceleration phases or high speed driving. This ZEV mode affords the driver «good citizen» mobility par excellence thanks to the total absence of exhaust emissions and noise pollution.

Technical description of main specific components

The electric motor is of the synchronous type with permanent magnets, developing a continuous power of 16 kW and a torque of 80 Nm. However, intermittently its output can attain 23 kW and 130 Nm.

The inverter regulates the 150 to 260 volt current from the high voltage battery pack to supply the electric motor in accordance with torque requirements determined by the PTMU.

A new generation battery pack delivers an output of 200 volts. It is housed in the spare wheel well without affecting the boot volume. The batteries are the Ni-MH type (Nickel Metal Hydride).

The converter converts the 200 V from the battery pack into 12 V to supply vehicle equipment in phases of solely electrical operation.

Managed braking maximises recharging of the batteries during phases of deceleration and braking. Intelligent control of the braking optimises the distribution between regenerative electric braking and traditional dissipative hydraulic braking. The braking management system gives priority to braking efficiency over the recovery of energy.