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The previously developed power-based fuel consumption theory for Internal Combustion Engine Vehicles (ICEV) is extended to Battery Electric Vehicles (BEV). The main difference between the BEV model structure and the ICEV is the bi-directional character of traction motors and batteries. A traction motor model was developed as a bi-linear function of positive and negative traction power. Another difference is that the accessories and cabin heating are powered directly from the battery, and not from the powertrain. The resulting unified model for ICEV and BEV energy consumption has linear terms proportional to positive and negative traction power, accessory power, and overhead, in varying proportions. Compared to the ICEV, the BEV powertrain has a high marginal efficiency and low overhead. As a result, BEV energy consumption data under a wide range of driving conditions are mainly proportional to net traction power, with only a small offset.

Advanced features in automotive systems often necessitate the management of complex interactions between subsystems. Existing control strategies are designed for certain levels of robustness, however their performance can unexpectedly deteriorate in the presence of significant uncertainties, resulting in undesirable system behaviors. This limitation is further amplified in systems with complex nonlinear dynamics. Hydro-mechanical clutch actuators are among those systems whose behaviors are highly sensitive to variations in subsystem characteristics and operating environments. In a P2 hybrid propulsion system, a wet clutch is utilized for cranking the engine during an EV-HEV mode switching event. It is critical that the hydro-mechanical clutch actuator is stroked as quickly and as consistently as possible despite the existence of uncertainties. Thus, the quantification of uncertainties on clutch actuator behaviors is important for enabling smooth EV-HEV transitions.

In 1985, the Body Division of the Automotive Corrosion and Prevention Committee of SAE (ACAP) concluded that an automotive body corrosion survey for public consumption was needed. The committee proceeded to develop a survey methodology and conducted surveys in the Detroit area every second year starting in 1985. The survey is a closed car parking lot survey of nineteen panels or partial panels checking for perforations, blisters and surface rust. Similar surveys have and will continue to be conducted at biyearly intervals for comparison purposes to track the results of industry wide corrosion protection “improvements”. This is a report of the results of the first three surveys. THE ACAP COMMITTEE BODY DIVISION has now completed the third in its series of biyearly surveys. It is now possible to see some very clear results of industry actions and some indication of future performance.

This paper presents a Short Time Fourier Transform based algorithm to identify unknown parameters in fuel dynamics system during engine cold start and warm-up. A first order system is used to model the fuel dynamics in a port fuel injection engine. The feed forward transient fuel compensation controller is designed based on the identified model. Experiments are designed and implemented to verify the proposed algorithm. Different experiment settings are compared.

Direct bypass to DC-DC boost converter in traction inverter increases converter's capability and efficiency significantly by providing a lower loss path for power flow between the battery and DC-link terminal. A bypass using diode is an excellent solution to achieve this capability at low cost and system complexity. Bypass diode operates in the linear operating region (DC Q-point) when the battery discharges through the bypass diode to drive the electric motors. Therefore, thermal stress on the DC-link capacitor is shared between the input and DC-link capacitors through the bypass diode. On the other hand, inverters introduce voltage oscillation in the DC-link terminal which results in unwanted energy oscillation through the bypass diode during battery charging. Both of these phenomena have been explained in details.

This paper discusses the development and execution of a unique one-day, hands-on seminar designed to introduce top-level manufacturing managers to the computer. Total emphasis is on manufacturing applications, and each manager is afforded an opportunity to use the computer himself. The mystery of data cards, teletype terminals, and CRTs is removed during line balancing, simulation, and process control work sessions. The seminar was developed by General Motor's Manufacturing Development Activity for internal presentation to GM managers.

This paper describes the major electrical characteristics of the automotive power supply system. It is a compilation of existing data and new information that will be helpful to both the electrical component and electronic assembly designers. Previously available battery/alternator data is organized to be useful to the designer. New dynamic information on battery impedance is displayed along with “cogging” transients, regulation limits and load dump characteristics.

In this paper, the high-temperature capability of the traction inverter was investigated by applying coolant with temperature much higher than the typical allowed value until the system fails. The purpose of this study is to identify the weakest link of the traction inverter system in terms of temperature. This study was divided into two stages. In the first stage, a series of nondestructive tests were carried out to investigate temperature rise (ΔT) of the key component above coolant temperature as a function of the outside controllable parameters-i.e., dc link voltage, phase current, and switching frequency. The key components include power modules, gate driver board, gate driver power supply, current sensors and dc link capacitor. Their temperatures were monitored by thermocouples or on-die temperature sensors.

A hybrid electric vehicle (HEV) can utilize the electromechanical path to optimize the ICE operation and implement the regenerative brake, the fuel economy of a vehicle therefore gets improved significantly. Bi-directional Boost converter is usually used in an electric drive system to boost the high voltage (HV) battery voltage to a higher dc-link voltage. The main advantages for a system with Boost converter is that the traction inverter is de-coupled from battery voltage variations causing it to be over-sized. When designing this Boost converter, the switching frequency is a key parameter for the converter design. Higher switching frequency will lead to higher switching loss of power device (IGBT +diode), moreover, it has significant impact on inductor ripple current, HV battery ripple current and input capacitor current. Therefore, the switching frequency is one of the most important parameters for the design and selection of both active and passive components.

Two of the most commonly exercised standards for electromagnetic compatibility (EMC) by automotive engineers are CISPR 12 and CISPR 25. While CISPR 12 is imposed as a regulation to ensure uninterrupted communication for off-board receivers, CISPR 25 is often applied to ensure the quality of services of on-board receivers. Performing these tests becomes challenging until the vehicle is prototyped which may prolong the production time in case of failure or need for modification. However, conducting these tests in a simulation environment can offer more time and cost-efficient ways of analyzing the electromagnetic environment of automotive vehicles. In this paper, a computational approach is proposed in order to predict electromagnetic disturbance from on-board electronics/electrical systems using 3D computational electromagnetic (CEM) tool; Altair Feko.

Modeling of High Voltage (HV) wires is an important aspect of vehicle safety simulations for electrified powertrains to understand the potential tearing of the wire sheath or pinching of HV wiring. The behavior of the HV wires must be reviewed in safety simulations to identify potential hazards associated with HV wire being exposed, severed, or in contact with ground planes during a crash event. Modeling HV wire is challenging due to the complexity of the physical composition of the wire, which is usually comprised of multiple strands bundled and often twisted together to form the HV electrical conductor. This is further complicated by the existence of external insulating sheathing materials to prevent HV exposure during normal operating conditions. This paper describes a proposed method to model and characterize different types of HV wires for usage in component- and vehicle-level safety models.

The detection and diagnosis of sensor faults in real-time is necessary for satisfactory performance of vehicle Electronic Stability Control (ESC) and Roll Stability Control (RSC) systems. This paper presents an observer designed to detect faults of a roll rate sensor that is robust to model uncertainties and disturbances. A reference vehicle roll angle estimate, independent of roll-rate sensor measurement, is formed from available ESC inertial sensor measurements. Residuals are generated by comparing the reference roll angle and roll rate, with the observer outputs. Stopping rules based on the current state of the vehicle and the magnitude of the residuals are then used to determine if a sensor fault is present. The system’s low order allows for efficient implementation in real-time on a fixed-point microprocessor. Modification of the roll rate sensor signal during in vehicle experiments shows the algorithm’s ability to detect faults.

A series of cold start experiments using a 2.0 liter gasoline turbocharged direct injection (GTDI) engine with custom controls and calibration were carried out using gasoline and iso-pentane fuels, to obtain the cold start emissions profiles for the first 5 firing cycles at an ambient temperature of 22°C. The exhaust gases, both emitted during the cold start firing and emitted during the cranking process right after the firing, were captured, and unburned hydrocarbon emissions (HC), CO, and CO2 on a cycle-by-cycle basis during an engine cold start were analyzed and quantified. The HCs emitted during gasoline-fueled cold starts was found to reduce significantly as the engine cycle increased, while CO and CO2 emissions were found to stay consistent for each cycle. Crankcase ventilation into the intake manifold through the positive-crankcase ventilation (PCV) valve system was found to have little effect on the emissions results.

Plug-in hybrid (PHEV) technology offers the ability to achieve zero tailpipe emissions coupled with convenient refueling. Fleet adoption of PHEVs, often motivated by organizational and regulatory sustainability targets, may not always align with optimal use cases. In a car rental application, barriers to improving fuel economy over a conventional hybrid include: diminished benefits of additional battery capacity on long-distance trips, sparse electric charging infrastructure at the fleet location, lack of renter understanding of electric charging options, and a principle-agent problem where the driver accrues fewer benefits than costs for actions that improve fuel economy, like charging and eco-driving. This study uses high-resolution driving data collected from twelve Ford Fusion Energi sedans owned by University of California, Davis (UC Davis), where the vehicles are rented out for university-related activities.

A predictive model for the mating forces of hand-plug connectors has been developed; it calculates the forces in a connector that has empty cavities instead of terminals in every position. Force data is needed as a check to see if connectors meet the latest ergonomic requirements in their as-built configurations. Historically, force data has been generated from physical testing since prior predictive models were not accurate enough. Testing is expensive and slow so a more advanced and accurate model was created. The model presented in this paper is accurate enough to replace mechanical force testing of partially-filled hand-plug connectors.

Fossil energy diversity and security along with environmental emission policies demand new energy carriers and associated technologies in the future. One of the major challenges of the automotive industry and research institutes worldwide currently is to develop and realize alternative fuel concepts for passenger cars. In line with Ford's global hydrogen vehicle program, different onboard hydrogen storage technologies are under investigation. In general, hydrogen storage methods can be categorized as either physical storage of hydrogen (i.e. compressed, liquid, or cryo-compressed) or material based hydrogen storage. Currently, automotive OEMs have only introduced hydrogen fleet vehicles that utilize physical-based hydrogen storage systems but they have recognized that hydrogen storage systems need to advance further to achieve the range associated with today's gasoline vehicle.

Ford's H2RV (Hydrogen Hybrid Research Vehicle) uses a Hydrogen fueled Internal Combustion Engine. This engine has a higher compression ratio and a faster fuel-burning rate compared to a conventional gasoline engine. The conventional flywheel is replaced with an electric motor in the hybrid powertrain, which causes higher crankshaft torsionals and is a major NVH source. The engine has a centrifugal supercharger mounted on its front-end dress, which is a big source of NVH. Fans are used to cool the high voltage batteries and to provide ventilation of H2 in the case of a leakage. The body sheet metal has several holes for passive H2 ventilation, battery cooling, plumbing lines, and harness routing. Underhood hardware, due to the hybrid transmission and the H2 ICE, created major packaging challenges for the intake and FEAD NVH. The exhaust muffler volume was limited due to the installation of high voltage batteries and underbody H2 fuel tanks.

Velocity profiles for air flowing under a vehicle body are determined by analyzing videotapes of neutrally buoyant soap bubbles using motion analysis software and equipment. What had heretofore been primarily a qualitative flow visualization technique has been extended to provide quantitative data. The light sources, cameras, and bubble generator, mounted on the vehicle, are powered by the vehicle's electrical system, making it possible to compare underbody velocities measured in a wind tunnel with those over the road. Results are presented for a heavy-duty 4×4 pickup truck at speeds up to 25m/s (55 mph). The velocity profiles in the tunnel and on the road were quite similar.

Auto-manufacturers are under increasing pressure to develop powertrain systems for automotive vehicles, which are more efficient regarding fuel consumption, less polluting and still keep high performance levels. Hybrid electrical vehicles (HEV) are considered the most promising technology in sight, considering a time horizon of more ore less twenty years. HEVs combine benefits of electrical vehicles, such zero emission, low noise and high torques at low velocities and advantages of conventional vehicles, such as large autonomy, great reliability and high levels of performance. This paper is focused on the major elements of an HEV powertrain: electrical motors, internal combustion engine (ICE) and batteries, which are described. The paper also presents a comparison of two possible HEV configurations: series and parallel. The mathematical model of a small hybrid vehicle is developed using software ADVISOR.

Boost converter is widely applied to hybrid electric vehicles (HEV). Typical control methods employ two proportional-integral (PI) regulators to fulfill DC bus voltage closed-loop control and inductor current closed-loop control, respectively. They have intrinsic performance limitations: 1) slow dynamic response of DC bus voltage regulation; 2) high overshoot voltage during transient state; 3) it is difficult to design four gains best fit all operational conditions. This paper proposes a model prediction based boost converter control method for HEV applications. The proposed control method employs model based instantaneous power prediction and dynamic optimization in real time by minimizing a defined cost function to overcome above issues. First of all, the issues of typical control methods are analyzed. Then, the proposed control method is presented in detail, followed by simulation verification and comparison with PI based control method.