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Wide attention to fuel cell electric vehicles (FCEVs) comes from two huge issues currently the world is facing with: the concern of the petroleum reserves depletion due to consequent oil dependence and the earth global warming due in some extent to vehicle emissions. In this background, Hyundai, along with its sister company Kia, has been building the FCEVs and operating their test fleet with several tens of units at home and abroad. Since 2004, 32 passenger vehicles have been offered for the Department of Energy's controlled hydrogen fleet and infrastructure demonstration and validation project in the U.S. In the meantime, from 2006, 30 passenger vehicles as well as four buses, featuring the in-house developed fuel cell stack and its associated components, are currently under the domestic operation for the FCEV learning demonstration led by the Ministry of Knowledge and Economy.

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.

In hybrid and electric vehicles, the control of the electric motor is a critical component of vehicle functions such as motoring, generating, engine-starting and braking. The efficient and accurate control of motor torque is performed by the motor controller. It is a complex system incorporating sensor sampling, data processing, controls, diagnostics, and 3-phase Pulse Width Modulation (PWM) generation which are executed in sub-100 uSec periods. Due to the fast execution rates, care must be taken in the software coding phase to ensure the algorithms will not exceed the target processor's throughput capability. Production motor control development often still follows the path of customer requirements, component requirements, simulation, hand-code, and verification test due to the concern for processor throughput. In the case of vehicle system controls, typically executed no faster than 5-10 mSec periods, auto-coding tools are used for algorithm development as well as testing.

As fuel prices continue to rise automotive manufacturers continue to push their suppliers to provide technology that improves the potential fuel efficiency of their applications. In addition there is an increasing trend towards smaller, lighter and more compact vehicles to mitigate the automotive carbon footprint. These movements necessitated the development of a new compact, low mass, variable displacement compressor to match the requirements for these smaller and more efficient vehicles. The new Delphi MVC, or Miniature Variable Compressor, meets these requirements by integrating the high efficiency of our latest swashplate variable compressor design into a compact and lightweight package. This design can be offered in a range of displacements from 80 to 100cc and can be offered as either internally or externally controlled to support the customer's needs.

This paper presents an adaptation method of equivalent factor in equivalent consumption minimization strategy (ECMS) of fuel cell hybrid electric vehicle (FCHEV) using hilly road information. Instantaneous optimization approach such as ECMS is one of real-time controllers. Furthermore, it is widely accepted that ECMS achieves near-optimum results with the selection of the appropriate equivalent factor. However, a lack of hilly road information no longer guarantees near-optimum results as well as charge-sustaining of ECMS under hilly road conditions. In this paper, first, an optimal control problem is formulated to derive ECMS analytical solution based on simplified models. Then, we proposed updating method of equivalent factor based on sensitivity analysis. The proposed method tries to mimic the globally optimal equivalent factor trajectory extracted from dynamic programming solutions.

Traditional vehicle air conditioning systems condition the entire cabin to a comfortable range of temperature and humidity regardless of the number of passengers in the vehicle. The A/C system is designed to have enough capacity to provide comfort for transient periods when cooling down a soaked car. Similarly for heating, the entire cabin is typically warmed up to achieve comfort. Localized heating and cooling, on the other hand, focuses on keeping the passenger comfortable by forming a micro climate around the passenger. This is more energy efficient since the system only needs to cool the person instead of the entire cabin space and cabin thermal mass. It also provides accelerated comfort for the passenger during the cooling down periods of soaked cars. Additionally, the system adapts to the number of passengers in the car, so as to not purposely condition areas that are not occupied.

The progressive trend towards the GDi engine downsizing, the focus on better fuel efficiency and performance, and the regulatory requirements with respect to the combustion emissions have brought the focus of attention on strategies for improvement of in-cylinder mixture preparation and identification and elimination of the sources of combustion emissions, in particular the in-cylinder particulate formation. This paper discusses the fuel system components, injector dynamics, spray characteristics and the single cylinder engine combustion investigation of a 40 [MPa] capable conventional GDi inwardly-opening multi-hole fuel injection system. It provides results of a study of the influence of fuel system pressure increase between 5 [MPa] to 40 [MPa], in conjunction with the injector static flow and spray pattern, on the combustion characteristics, specifically the particulate and gaseous emissions and the fuel economy.

In previous work, Gasoline Direct Injection Compression Ignition (GDCI) has demonstrated good potential for high fuel efficiency, low NOx, and low PM over the speed-load range using RON91 gasoline. In the current work, a four-cylinder, 1.8L engine was designed and built based on extensive simulations and single-cylinder engine tests. The engine features a pent roof combustion chamber, central-mounted injector, 15:1 compression ratio, and zero swirl and squish. A new piston was developed and matched with the injection system. The fuel injection, valvetrain, and boost systems were key technology enablers. Engine dynamometer tests were conducted at idle, part-load, and full-load operating conditions. For all operating conditions, the engine was operated with partially premixed compression ignition without mode switching or diffusion controlled combustion.

The focus of this study is investigation of the influence of fuel system pressure, intake tumble charge motion and injector seat specification - namely the static flow and the plume pattern - on the GDi engine particulate emissions under the homogenous combustion operation. The paper presents the spray characteristics and the single cylinder engine combustion data for the Delphi Multec® 14 GDi multi-hole fuel injector, capable of 40 [MPa] fuel system pressure. It provides results of a study of the influence of fuel pressure increase between 5 [MPa] to 40 [MPa], for three alternative seat designs, on the combustion characteristics, specifically the particulate and gaseous emissions and the fuel consumption. In conjunction with the fuel system pressure, the effect of enhanced charge motion on the combustion characteristics is investigated.

In order to extend the operability limit of the gasoline compression ignition (GCI) engine, as an avenue for low temperature combustion (LTC) regime, the effects of parametric variations of engine operating conditions on the performance of six-stroke GCI (6S-GCI) engine cycle are numerically investigated, using an in-house 3D CFD code coupled with high-fidelity physical sub-models along with the Chemkin library. The combustion and emissions were calculated using a skeletal chemical kinetics mechanism for a 14-component gasoline surrogate fuel. Authors’ previous study highlighted the effects of the variation of injection timing and split ratio on the overall performance of 6S-GCI engine and the unique mixing-controlled burning mode of the charge mixtures during the two additional strokes. As a continuing effort, the present study details the parametric studies of initial gas temperature, boost pressure, fuel injection pressure, compression ratio, and EGR ratio.

As the emissions and fuel economy standards for internal combustion engines become ever more stringent, a variety of valvetrain control methods have been developed to improve engine performance. One of these is camshaft (CAM) phasing, which controls the angular position of the CAM relative to the crankshaft allowing changes to the timing of valve lift events. This method has demonstrated advantages including broadening the engine torque curve, increasing peak power at higher RPM, reducing hydrocarbon and NOx emissions, and improving fuel economy. In addition, external EGR systems can be eliminated because internal cylinder dilution control can be achieved by varying CAM timing. Current implementations of CAM phasing use oil-pressure-based electro-mechanical systems. While these systems are relatively low cost and have proven to be robust, they have disadvantages at low oil temperatures and pressures (such as during cranking events).

The series-parallel hybrid electric vehicle(HEV), which employs a planetary gear set to combine one internal combustion engine(ICE) and two electric motors(EMs), can take advantages of both series and parallel hybrid system. The efficient powertrain operating point of the system can be obtained by the instantaneous optimization of equivalent fuel consumption. However, heavy computational requirements and variable constraints of the optimization process make it difficult to build real-time control strategy. To overcome the difficulty, this study suggests the control strategy which divides the optimization process into 2 stages. In the first stage, a target of charge/discharge power is determined based on equivalent fuel consumption, then in the second stage, an engine operating point is determined taking power transfer efficiency into account.

In order to investigate the characteristics of top ring groove deposit formation in gasoline and diesel engine, engine test and simulation test were performed. From component analysis of used oils sampled from actual running engines, oxidation and nitration for gasoline engine and soot content for diesel engine were selected as main parameters for evaluating oil degradation. In gasoline engine, deposit formation increases linearly with oxidation and nitration, and especially, oil oxidation is a dominant factor on the deposit formation rather than nitration. And, deposit formation increases gradually in low temperature ranges below 260°C even if oils are highly oxidized, but it increases rapidly if piston top ring groove temperature is above 260°C. In diesel engine, deposit formation is highly related to soot content in lubricating oils.

In this study, a series of tests have been carried out to evaluate the effects of the injection rate and timing on bsfc, NOx, and PM emissions in a heavy-duty diesel engine with TICS FIE system. Injection line pressure, cylinder pressure, NOx and smoke were measured with various injection times and injection rates. The injection rate was altered at a fixed injection timing, which could be realized either by changing the TICS setting time or by using different cam profiles. The injection time was varied by using TICS timing control function at a given setting time. A parametric study of the injection rate in in-line pump system was tried to correlate injection rate variations with combustion characteristics and emission. Two parameters, the injection pressure rising rate and the initially injected fuel quantity were introduced to characterize fuel injection.

Supervisory control strategy of a hybrid electric vehicle (HEV) provides target powers and operating points of an internal combustion engine and an electric motor. To promise efficient driving of the HEV, it is needed to find the proper values of control parameters which are used in the strategy. However, it is very difficult to find the optimal values of the parameters by doing experimental tests, since there are plural parameters which have dependent relationship between each other. Furthermore variation of the test results makes it difficult to extract the effect of a specific parameter change. In this study, a model based parameter optimization method is introduced. A vehicle simulation model having the most of dynamics related to fuel consumption was developed and validated with various experimental data from real vehicles. And then, the supervisory control logic including the control parameters was connected to the vehicle model.

A vehicle drifts due to several reasons from its intended straight path even in the case of no steering input. The multibody dynamic analysis of vehicle drift during accelerating and braking are performed. This paper focuses on modeling and evaluating effects of suspension parameters, differential friction, engine mounting and C.G. location of the vehicle under multibody dynamic simulation environment. Asymmetry of geometry and compliance between left and right side is considered cause of drift. The sensitivities of the suspension parameters are presented for each driving condition. In case of acceleration, the interaction of differential friction and driveshaft stiffness and their influence on drift are also studied. For braking condition, suspension parameters such as initial toe variation of rear coupled torsion beam axle type suspension and kingpin inclination deviation of front suspension are studied including the braking force difference.

In order to understand the relationship between the location of piston ring gap and instantaneous change of oil consumption during engine operation, the ring rotation and instantaneous oil consumption were measured simultaneously in a hydrogen fueled single cylinder spark ignition engine. A radioactive-tracer technique was used to measure the rotational movement of piston ring. Two kinds of isotopes(60Co and 192Ir) with different energy level were mounted to the top and 2nd rings to measure each ring's movement independently. The instantaneous oil consumption was obtained by analyzing CO2 concentration in exhaust gas. From the result of ring rotational movement, typical patterns of ring rotation were obtained as follows; Rotational movements are usually initiated by changing the operating conditions. Piston rings tend to rotate easily under low load condition. The rotation speed of ring usually ranged in 0.2∼0.4 rev/min for top ring and 0.5∼0.6 rev/min for 2nd ring.

In a multi-cylinder variable valve lift (VVL) engine, in spite of its high efficiency and low emission performance, operation of the variable valve lift brings about not only variation of the air-fuel ratio at the exhaust manifold, but also individual cylinder air-fuel ratio maldistribution. In this study, in order to reduce the air-fuel ratio variation and maldistribution, we propose an individual cylinder air-fuel ratio estimation algorithm for individual cylinder air-fuel ratio control. For the purpose of the individual cylinder air-fuel ratio estimation, air charging dynamics are modeled according to valve lift conditions. In addition, based on the air charging model, individual cylinder air-fuel ratios are estimated by multi-rate sampling from single universal exhaust gas oxygen (UEGO) sensor located on the exhaust manifold. Estimation results are validated with a one-dimensional engine simulation tool.

In the present study, we developed a CVVL (Continuously Variable Valve Lift) engine. The CVVL mechanism is Hyundai Motor Company's own design, which is characterized by its compactness. The CVVL engine was developed without the increase of the engine height, thus the same hood line of the vehicle could be used with the base engine; the base engine does not adopt the CVVL technology, and it has the same engine specification other than valvetrain system. The CVVL mechanism was based on a six-linkage mechanism. Although the valvetrain friction of the CVVL engine of the six-linkage is higher than the base engine when operated with the same valve lift, it is in a competitive level compared to the other engines produced by HMC. The fuel consumption of the CVVL engine has been reduced by more than 5% compared to the base engine, and this is mainly thanks to the reduction of the pumping loss and friction.

A technical approach to reduce NOx and to minimize the fuel consumption caused by the DeNOx aftertreatment system was introduced. The NEDC mode test of the HMC (Hyundai Motor Company) DeNOx system was done with a Euro 5 vehicle (ETW (Equivalent Test Weight) = 1,810 kg, 143 kW, 430 N⋅m), which resulted in that the Euro 6 legislation standards were met. The NOx and HC emissions were, respectively, measured to be 0.059 g/km and 0.087 g/km with the hydrothermal-aged catalysts, and CO₂ was increased by ≺ 4%.