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The three major challenges in the power electronics in hybrid and electric vehicles are: System cost, power density and reliability. High temperature power device and packaging technologies increases the power density and reliability while reducing system cost. Advanced Silicon devices with synthesized high-temperature packaging technologies can achieve junction temperature as high as 200C (compared to the present limitation of 150C) eliminating the need for a low-temperature radiator and therefore these devices reduces the system cost. The silicon area needed for a power inverter with high junction temperature capability can be reduced by more than 50 - 75% thereby significantly reducing the packaging space and power device and package cost. Smaller packaging space is highly desired since multiple vehicle platforms can share the same design and therefore reducing the cost further due to economies of scale.

Previous research has shown that elevating fuel injection pressure results in better air-fuel mixture formation, allowing for a further increase in maximum exhaust gas recirculation (EGR) rate while consequently reducing NOx emissions. The aim of this paper is to find out whether there is an optimum injection pressure for lowest soot-NOx emissions at a given boost pressure in high-speed diesel engines. Experiments are carried out on a single-cylinder research engine with a prototype common-rail system, capable of more than 200 MPa injection pressure. The effect of injection pressure on soot-NOx formation is investigated for a variety of boost conditions, representing the conditions of single to multi-stage turbocharger systems. Analysis of the data is performed at the application relevant soot to NOx ratio of approximately 1:10. It is observed that above a critical injection pressure, soot-NOx emissions are not reduced any further.

Active safety systems will have a great impact in the next generation of vehicles. This is partly originated by the increasing consumer's interest for safety and partly by new traffic safety laws. Control actions in the vehicle are based on an extensive environment model which contains information about relevant objects in vehicle surroundings. Sensor data fusion integrates measurements from different surround sensors into this environment model. In order to avoid system malfunctions, high reliability in the interpretation of the situation, and therefore in the environment model, is essential. Hence, the main idea of data fusion is to make use of the advantages of using multiple sensors and different technologies in order to fulfill these requirements, which are especially high due to autonomous interventions in vehicle dynamics (e. g. automatic emergency braking).

Regarding the strongly growing two-wheeler market fuel economy, price and emission legislations are in focus of current development work. Fuel economy as well as emissions can be improved by introduction of engine management systems (EMS). In order to provide the benefits of an EMS for low cost motorcycles, efforts are being made at BOSCH to reduce the costs of a port fuel injection (PFI) system. The present paper describes a method of how to reduce the number of sensors of a PFI system by the use of sophisticated software functions based on high-resolution engine speed evaluation. In order to improve the performance of a system working without a MAP-sensor (manifold air pressure sensor) an air charge feature (ACFn) based on engine speed is introduced. It is shown by an experiment that ACFn allows to detect and adapt changes in manifold air pressure. Cross-influences on ACFn are analyzed by simulations and engine test bench measurements.

A variety of methodologies to use embedded multicore controllers efficiently has been discussed in the last years. Several assumptions are usually made in the automotive domain, such as static assignment of tasks to the cores. This paper shows an approach for efficient task allocation depending on different system modes. An engine management system (EMS) is used as application example, and the performance improvement compared to static allocation is assessed. The paper is structured as follows: First the control algorithms for the EMS will be classified according to operating modes. The classified algorithms will be allocated to the cores, depending on the operating mode. We identify mode transition points, allowing a reliable switch without neglecting timing requirements. As a next step, it will be shown that a load distribution by mode-dependent task allocation would be better balanced than a static task allocation.

The newly released Distributed System Interface 3 (DSI3) Bus Standard specification defines three modulation levels form which 16 valid symbols are coded. This complex structure is best decoded with symbol pattern recognition. This paper proposes a simplification of the correlation score calculation that sharply reduces the required number of operations. Additionally, the paper describes how the pattern recognition is achieved using correlation scores and a decoding algorithm. The performance of this method is demonstrated by mean of simulations with different load models between the master and the sensors and varying noise injection on the channel. We prove than the pattern recognition can decode symbols without any error for up to 24dBm.

In order to comply with more and more stringent emission standards, like EU6 which will be mandatory starting in September 2014, GDI engines have to be further optimized particularly in regard of PN emissions. It is generally accepted that the deposition of liquid fuel wall films in the combustion chamber is a significant source of particulate formation in GDI engines. Particularly the wall surface temperature and the temperature drop due to the interaction with liquid fuel spray were identified as important parameters influencing the spray-wall interaction [1]. In order to quantify this temperature drop at combustion chamber surfaces, surface temperature measurements on the piston of a single-cylinder engine were conducted. Therefore, eight fast-response thermocouples were embedded 0.3 μm beneath the piston surface and the signals were transmitted from the moving piston to the data acquisition system via telemetry.

Cost reduction of engine management systems (EMS) for two-wheeler applications is the key to utilize their potentials compared to carburetor bikes regarding emissions, fuel economy and system robustness. In order to reduce the costs of a system with port fuel injection (PFI) Bosch is developing an EMS without a manifold air pressure (MAP) sensor. The pressure sensor is usually used to compensate for different influences on the air mass, which cannot be detected via the throttle position sensor (TPS) and mean engine speed. Such influences are different leakage rates of the throttle body and changing ambient conditions like air pressure. Bosch has shown in the past that a virtual sensor relying on model based evaluation of engine speed can be used for a detection of leakage air mass in idling to improve the pre-control of the air-fuel ratio. This provides a functionality which so far was only possible with an intake pressure sensor.

In-vehicle communication faces increasing bandwidth demands, which can no longer be met by today's MOST150, FlexRay or CAN networks. In recent years, Fast Ethernet has gained a lot of momentum in the automotive world, because it promises to bridge the bandwidth gap. A first step in this direction is the introduction of Ethernet as an On Board Diagnostic (OBD) interface for production vehicles. The next potential use cases include the use of Ethernet in Driver Assistance Systems and in the infotainment domain. However, for many of these use cases, the Fast Ethernet solution is too slow to move the huge amount of data between the Domain Controllers, ADAS Systems, Safety Computer and Chassis Controller in an adequate way. The result is the urgent need for a network technology beyond the Fast Ethernet solution. The question is: which innovation will provide enough bandwidth for domain controllers, fast flashing routines, video data, MOST-replacement and internal ECU buses?

In order to optimize spray layouts of commonly used high-pressure injectors for gasoline direct injection (GDI) engines featuring multi-hole valve seats, a detailed understanding of the cause-effect relation between inner spray hole geometries and inner flow conditions, initializing the process of internal mixture formation, is needed. Therefore, a novel measurement setup, capable of determining spray hole individual mass flow rates, is introduced and discussed. To prove its feasibility, a 2-hole configuration is chosen. The injected fuel quantities are separated mechanically and guided to separate pressure tight measurement chambers. Each measurement chamber allows for time resolved mass flow rate measurements based on the HDA measurement principle (German: “Hydraulisches Druck-Anstiegsverfahren”).

Recently, vehicle networks have increased complexity due to the demand for autonomous driving or connected devices. This increasing complexity requires high bandwidth. As a result, vehicle manufacturers have begun using Ethernet-based communication for high-speed links. In order to deal with the heterogeneity of such networks where legacy automotive buses have to coexist with high-speed Ethernet links vehicle manufacturers introduced a vehicle gateway system. The system uses Ethernet as a backbone between domain controllers and CAN buses for communication between internal controllers. As a central point in the vehicle, the gateway is constantly exchanging vehicle data in a heterogeneous communication environment between the existing CAN and Ethernet networks. In an in-vehicle network context where the communications are strictly time-constrained, it is necessary to measure the delay for such routing task.

A main challenge when developing next generation architectures for automated driving ECUs is to guarantee reliable functionality. Today’s fail safe systems will not be able to handle electronic failures due to the missing “mechanical” fallback or the intervening driver. This means, fail operational based on redundancy is an essential part for improving the functional safety, especially in safety-related braking and steering systems. The 2-out-of-2 Diagnostic Fail Safe (2oo2DFS) system is a promising approach to realize redundancy with manageable costs. In this contribution, we evaluate the reliability of this concept for a symmetric and an asymmetric Electronic Power Steering (EPS) ECU. For this, we use a Markov chain model as a typical method for analyzing the reliability and Mean Time To Failure (MTTF) in majority redundancy approaches. As a basis, the failure rates of the used components and the microcontroller are considered.

Due to the new CO2 targets for vehicles, electrification of powertrains and operation strategies for electrified powertrains have drawn more attention. This article presents a predictive multi-objective operation strategy for hybrid electric vehicles (HEVs), which simultaneously minimizes the fuel consumption and the cycle aging of traction batteries. This proposed strategy shows better performance by using predictive information and high robustness to inaccuracy of predictive information. In this work, the benefits of the developed operation strategies are demonstrated in a strong hybrid electric vehicle (sHEV) with P2-configuration. For the cycle aging of a lithium-ion battery, an empirical model is built up with Gaussian processes based on experimental data.

Fully Variable Valve Actuation (FVVA) systems enable to employ a wide range of combustion strategies by providing the actuation of a gas exchange valve at an arbitrary point in time, with variable lift and adjustable ramps for opening and closing. Making such a system ready for the market requires appropriate fault-diagnostic functionality. Here, we focus on diagnosis possibilities by using air intake system sensors such as Manifold Absolute Pressure (MAP) sensors. Results obtained on a 4-cylinder test bench engine are presented for the early intake opening strategy under different loads, and at medium range rotational speeds on steady-state conditions. It is shown that detection and identification of the different critical faults on each actuator is possible by using a Fourier series signal model of the MAP sensor.

In addition to basic switching functionality, smart power switches mainly provide diagnostic and protection functions, e.g. for short circuits to the load, which makes it all the more surprising that short circuit protected smart switches have been used for years in automotive applications without there being a precise definition of a short circuit. This article describes what Infineon has done to fill this gap. It was first necessary to define the kind of short circuits likely to occur in automotive applications and to specify the use and operating points of the smart switches. The next logical step was the standardization of the test circuit and application conditions in the AEC (Automotive Electronics Council) to allow an industry-wide comparison of the test results.

In this article a new zero-dimensional model is presented for simulating the cylinder pressure in direct injection diesel engines. The model enables the representation of current combustion processes considering multiple injections, high exhaust gas recirculation rates, and turbocharging. In these methods solely cycle-resolved, scalar input variables from the electronic control unit in combination with empirical parameters are required for modeling. The latter are adapted automatically to different engines or modified applications using measured cylinder pressure traces. The verification based on measurements within the entire operating range from engines of different size and type proves the universal applicability and high accuracy of the proposed method.

The increasing number of electronic control units (ECUs) in vehicles leads to more and more complex systems with a steadily growing demand for data exchange. This growth includes the number of bus participants, the amount of data and hence the data transfer rates. In addition, the trend towards car-to-x connectivity reinforces the need for new in-vehicle communication solutions. Since the early 1990s Controller Area Network (CAN) is the most widely used powertrain bus system. Since 2000 FlexRay is used in addition to CAN in the premium segment. For classic powertrain applications, the data transfer rates of these bus systems are sufficient; however the utilization is sometimes difficult and gateways are often required. For new applications like hybrid and electric vehicles and the next generation of external communication applications (e.g. telematics services) new concepts based on the existing bus systems or completely new solutions are needed.

Due to the EU6 emission standard that will be mandatory starting in September 2014 the particulate emissions of GDI engines come into the focus of development. For this reason, soot and the mechanisms responsible for the soot formation are of particular importance. A very significant source of particulate emissions from engines with gasoline direct injection is the wall film formation. Therefore, the analysis of soot emission sources in the CFD calculation requires a detailed description of the entire underlying model chain, with special emphasis on the spray-wall interaction and the wall film dynamics. The validation of the mentioned spray-wall interaction and wall film models is performed using basic experimental investigations, like the infrared-thermography and fluorescence based measurements conducted at the University of Magdeburg.

Today's ABS sytems for commercial vehicles and trailers reflect specific solutions for individual vehicle model wiring and control features. In addition, the chassis mounting requirements for trailer applications uses a separate sealed housing for the relay and other sensitive components. A logical progression of design development resulted in the new ABS 6S/4K open system with the ability of being adaptable to specific vehicle control requirements. A variety of different component arrangements can be accommodated. Accordingly, it does not require a standard wiring harness. Wiring is left optional for the specific vehicle configuration. The housing may be frame mounted without any special protection and therefore can cover both trailer and tractor applications. The housing is designed to provide necessary protection from water and dirt. The electronic senses the peripheral component configuration via a simple “learning” procedure.

An electronic control of throttle angle is required for safety systems like traction control (ASR) and for advanced engine management systems with regard to further improvements of driving comfort and fuel economy. For applications, in which only ASR is required, two versions of a new traction control actuator (TCA) have been developed. Their function is based on controlling the effective length of the bowden cable between the accelerator pedal and the throttle. Besides retaining the mechanical linkage to the throttle, the concept has no need for a pedal position sensor, which is necessary for a drive-by-wire system. Design and performance of both actuators are described and their individual advantages are compared. Moreover, the communication of the system with ASR and its behaviour with regard to vehicle dynamics are illustrated.