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Due to the diversity of Heavy Duty Vehicles (HDV), the European CO2 and fuel consumption monitoring methodology for HDVs will be based on a combination of component testing and vehicle simulation. In this context, one of the key input parameters that need to be accurately defined for achieving a representative and accurate fuel consumption simulation is the vehicle's aerodynamic drag. A highly repeatable, accurate and sensitive measurement methodology was needed, in order to capture small differences in the aerodynamic characteristics of different vehicle bodies. A measurement methodology is proposed which is based on constant speed measurements on a test track, the use of torque measurement systems and wind speed measurement. In order to support the development and evaluation of the proposed approach, a series of experiments were conducted on 2 different trucks, a Daimler 40 ton truck with a semi-trailer and a DAF 18 ton rigid truck.

The number of full electric and hybrid electric vehicles is rapidly growing [1][2][3]. The new technologies accompanying this trend are increasingly becoming a focal point of interest for rescue services. There is much uncertainty about the right techniques to free trapped occupants after an accident. The same applies to vehicle fires. Can car fires involving vehicles with a lithium ion traction battery be handled in the same way as conventional vehicle fires? Is water the right extinguishing agent? Is there a risk of explosion? There are many unanswered questions surrounding the topic of electric vehicle safety. The lack of information is a breeding ground for rumours, misinformation and superficial knowledge. Discussions on various internet platforms further this trend. Tests were conducted on three lithium ion traction batteries, which were fuel-fired until burning on their own. The batteries were then extinguished with water, a surfactant and a gelling agent.

The new Sprinter targets the USA and Canada markets nationwide to reconfirm Daimlers statement for Diesel engine in vans. Consequentially, the MY2007 Sprinter follows his successful predecessor as again the first - and up to now the only - Diesel vehicle in its class now meeting even the strict EPA07 requirement in California. For the growing market in North America an unique development for the successor for the previous 5-cylinder Diesel Sprinter had been made. The new 3 liter V6 Diesel engine is based on numerous corporate wide versions from Mercedes and Chrysler Passenger cars and SUVs and has its roots also in smaller and larger Mercedes vans. Effective January 2007 the NAFTA04 requirements have been replaced by the NAFTA07 values. Meeting those led to significant changes of the latest Sprinter in European EURO4 version. Both, engine and exhaust hardware as well as the ECU-data had been modified consequentially.

Increasingly stringent requirements to improve fuel economy and reduce emissions are pushing the automotive industry toward more innovative solutions. To fulfill the demand, OEMs are developing hybrid systems with powerful electronics. The key technology is in all cases the battery. It is the most critical and expensive element of hybrid systems. The battery requires special care, as it must supply up to 400 Volts (V) and have a capacity of up to several kilowatt-hours (kWh). This paper will review the main functions of a Lithium-ion (Li-ion) battery management system, including power on/off, charging/discharging, and computation of the state of charge and state of health. In order to increase the battery lifespan, new functions such as active load balancing must be implemented.

Increasing fuel costs and emission regulations force the car manufacturers to develop powerful but efficient engines. The 3-liter car (3-liter/100 km fuel consumption → 80 miles/gallon) is one of the slogans. To fulfill these requirements a fully electronic controlled Engine Management is necessary. Carburetor systems are replaced by fuel injection systems. Direct injection for Diesel as well as for gasoline engines is the clear trend for the future. The mechanical throttle systems, used for a long time will not fit to the requirements of direct injection. A DC motor for electronic throttle control in conjunction with λ regulation and exhaust gas recirculation are the key elements for low emission cars. Also the automotive ignition system is in a process of change today.

An innovative way of lowering engine fuel consumption is to reduce engine displacement. However, smaller engines featuring reduced swept volume typically exhibit insufficient torque at low engine speeds. Conventional exhaust turbochargers are not able to compensate for this behavior and additionally suffer from the familiar turbo lag. One possible solution may be an electrically assisted turbocharger, with a high-speed motor providing the extra boost at low engine speeds. A critical factor for the efficiency of the concept is the ratio of the electric motor torque and the rotational mass inertia of the rotor. Testbench evaluation shows acceleration times of 0.5 seconds to reach speeds up to 70,000 rpm. Typically, the electrical load of such systems goes up to 3 kW. Target motors are various types of electrically commutated motors such as BLDC, switched reluctance or induction motors.

In the field of heavy-duty applications almost all engines apply the compression ignition principle, spark ignition is used only in the niche of CNG engines. The main reason for this is the high efficiency advantage of diesel engines over SI engines. Beside this drawback SI engines have some favorable properties like lower weight, simple exhaust gas aftertreatment in case of stoichiometric operation, high robustness, simple packaging and lower costs. The main objective of this fundamental research was to evaluate the limits of a SI engine for heavy-duty applications. Considering heavy-duty SI engines fuel consumption under full load conditions has a high impact on CO₂ emissions. Therefore, downsizing is not a promising approach to improve fuel consumption and consequently the focus of this work lies on the enhancement of thermal efficiency in the complete engine map, intensively considering knocking issues.

In order to reduce fuel consumption in Fuel Cell Electric Vehicles, effective distribution of power demand between Fuel Cell and Battery is required. Energy management strategies can improve fuel economy by meeting power demand efficiently. This paper explains development of various energy management strategies for Fuel Cell Electric Vehicle with Lithium Ion Battery. Drive cycles used for optimization and analysis of the strategies are New European Drive cycles (NEDC), Japanese Drive cycles (JAP1015), City Drive cycles, Highway Drive cycles (FHDS) and Federal Urban Drive cycles (FUDS). All Fuel consumption and ageing calculations are done using backward model implemented in MATLAB/SIMULINK.

Rising oil prices and increasing strict emission legislation force vehicle manufacturers to reduce fuel consumption of future vehicles. In order to meet this target, the process of converting fuel into useable energy and the use of this energy by the different energy-consuming vehicle's subsystems have to be examined. Vehicles' subsystems consist of energy-supplying, energy-consuming, and in some cases energy-storing components. Due to the high complexity of these systems and their interaction, optimization of their energy efficiency is a challenging task. By introducing individual operational strategies for each subsystem, it is possible to increase the energy efficiency for a specific function. To further improve the vehicle's overall energy efficiency, holistic control strategies are introduced that distribute the energy between the subsystems intelligently.

The constant motivation for lower fuel consumption and emission levels has always been in the minds of most auto makers. Therefore, it is important to have precise control of the fuel being delivered into the engine. Gasoline Port fuel injection has been a matured system for many years and cars sold in emerging markets still favor such system due to its less system complexity and cost. This paper will explain injection control strategy of today during development, and especially the injector dead-time compensation strategy in detail and how further improvements could still be made. The injector current profile behavior will be discussed, and with the use of minimum hardware electronics, this paper will show the way for a new compensation strategy to be adopted.

The overall efficiency of hybrid electric vehicles largely depends on the design and application of its energy management system (EMS). Despite the load coordination when operating the system in a hybrid mode, the EMS accounts for state changes between the different driving modes. Whether a transition between pure electric driving and internal combustion engine (ICE) powered driving is beneficial depends, among others, on the respective operation point, the route ahead as well as on the energetic expense for the engine start itself. The latter results from a complex interaction of the powertrain components and has a tremendous impact on the efficiency and quality of EMSs. Optimization based methods such as dynamic programming serve as benchmark for the design process of rule based control strategies. In case no energetic expenses are assigned to a state change, the resulting EMS suffers from being sub-optimal regarding the fuel consumption.

Future CO2 emission legislation requires the internal combustion engine to become more efficient than ever. Of great importance is the boosting system enabling down-sizing and down-speeding. However, the thermodynamic coupling of a reciprocating internal combustion engine and a turbocharger poses a great challenge to the turbine as pulsating admission conditions are imposed onto the turbocharger turbine. This paper presents a novel approach to a turbocharger turbine development process and outlines this process using the example of an asymmetric twin scroll turbocharger applied to a heavy duty truck engine application. In a first step, relevant operating points are defined taking into account fuel consumption on reference routes for the target application. These operation points are transferred into transient boundary conditions imposed on the turbine.

The worldwide automotive industry is currently preparing for a market introduction of hydrogen-fueled powertrains. These powertrains in fuel cell electric vehicles (FCEVs) offer many advantages: high efficiency, zero tailpipe emissions, reduced greenhouse gas footprint, and use of domestic and renewable energy sources. To realize these benefits, hydrogen vehicles must be competitive with conventional vehicles with regards to fueling time and vehicle range. A key to maximizing the vehicle's driving range is to ensure that the fueling process achieves a complete fill to the rated Compressed Hydrogen Storage System (CHSS) capacity. An optimal process will safely transfer the maximum amount of hydrogen to the vehicle in the shortest amount of time, while staying within the prescribed pressure, temperature, and density limits. The SAE J2601 light duty vehicle fueling standard has been developed to meet these performance objectives under all practical conditions.

The reduction of fuel consumption as well as the rising demands of customers regarding a vehicle’s driving dynamic and the legislator’s continually rising demands are a current issue in vehicle development. Hybrid vehicles offer a possibility to rise to this challenge. Realistic driving cycles are of utmost importance for the calibration of a hybrid vehicle’s operational strategy. Deriving replacement speed cycles from extensive customer data sets seems to be an approach for solving these problems. The contribution at hand describes the derivation of replacement cycles by using stochastic models, probabilistic (weighted) drawings and a combinatorial optimisation. The novelty value is that the characteristic influences of all drivers are being considered in the generation due to the stochastic modelling.

For highly automated driving, commercial vehicles require an Electric/Electronic (E/E) architecture, which - in addition to sensor fusion - ensures safety-critical processes such as steering and braking at all times. Among other things, a redundant 24 V supply with corresponding disconnection is required. The battery switch is a key component. Commercial, construction, and agricultural vehicles (CAV) need to operate at the highest possible availability and the lowest possible cost of ownership. This is why automated and autonomous driving has the potential to revolutionize the CAV sector. Driverless machines can be operated around the clock and almost non-stop. Platooning allows automated, interconnected trucks to drive in a convoy and very close to each other. Platooning saves fuel.