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With the increase of hotel and ancillary loads and replacement of engine driven mechanical and hydraulic loads with electrical loads, automotive systems are becoming more electric. This is the concept of More Electric Cars (MEC) that necessitates a higher system voltage, such as the proposed 42V, for conventional cars. In this paper, the development of the 42V electric power system for vehicle applications is reviewed. The system architecture and motor drive problems associated with the 42V electric power system are analyzed. Solutions to these problems are also discussed.

An electromechanical gear is presented along with design examples utilizing the electromechanical gear in hybrid electric vehicle drive trains. The designs feature the electromechanical gear (the Transmotor) in place of traditional mechanical transmissions and/or gearing mechanisms. The transmotor is an electric motor suspended by its shafts, in which both the stator and the rotor are allowed to rotate freely. The motor thus can provide positive or negative rotational energy to its shafts by either consuming or generating electrical energy. A design example is included in which the transmotor is installed on the output shaft of an internal combustion engine. In this arrangement the transmotor can either increase or decrease shaft speed by applying or generating electrical power, allowing the ICE to operate with a constant speed.

In this paper, a mild hybrid drive train has been proposed. A small electric motor with low rated voltage (42 V) is used to (1) propel the vehicle at low speed, (2) replace the fluid-coupled torque converter and (3) realize regenerative braking. With proper design and control, the fuel economy in urban driving can be significantly improved without much change from conventional drive train to the mild hybrid drive train.

The last quarter century has seen CO2 emissions increase at a steadily increasing rate. In the U.S.A. alone from 1970 to 1992 the CO2 emissions have increased from 5.5 billion metric tons of carbon dioxide to 6.6 bmt. The transportation industry contributes currently (1991 figures) 24.7% of the total emissions from the United States. Transportation utilization has grown faster, however, but more efficient vehicles allow for more travel without increasing the CO2 proportionally. The advancements made in the 1980s have reduced emissions by 21 million tons of CO2 per year on average. Electric Vehicles have been a proposed method of reducing the CO2 emissions due to transportation. Electric vehicles produce no emissions while driving, making them ideal candidates for heavily polluted and concentrated areas such as urban locations. However, it is debatable if electric vehicles are feasible on the global scale of CO2 reduction.

The Battery Performance and Cost Model (BatPaC), developed by Argonne National Laboratory, is a versatile tool designed for lithium-ion battery (LIB) pack engineering. It accommodates user-defined specifications, generating detailed bill-of-materials calculations and insights into cell dimensions and pack characteristics. Pre-loaded with default data sets, BatPaC aids in estimating production costs for battery packs produced at scale (5 to 50 GWh annually). Acknowledging inherent uncertainties in parameters, the tool remains accessible and valuable for designers and engineers. BatPaC plays a crucial role in National Highway Transportation Traffic Safety Administration (NHTSA) regulatory assessments, providing estimated battery pack manufacturing costs and weight metrics for electric vehicles. Integrated with Argonne's Autonomie simulations, BatPaC streamlines large-scale processes, replacing traditional models with lookup tables.

To reduce development time and introduce technologies faster to the market, many companies have been turning more and more to Model Based Design. In Model Based Design, the development process centers around a system model, from requirements capture and design to implementation and test. Engineers can skip over a generation of system design processes on the basis of hand coding and use graphical models to design, analyze, and implement the software that determines machine performance and behavior. This paper describes the process implemented in Autonomie, a Plug-and-Play Software Environment, to design and evaluate component hardware in an emulated environment. We will discuss best practices and provide an example through evaluation of advanced high-energy battery pack within an emulated Plug-in Hybrid Electric Vehicle.

The energy density and power density comparison of conventional fuels and batteries is often mentioned as an advantage of conventional vehicles over electric vehicles. Such an analysis often shows that the batteries are at least an order of magnitude behind fuels like gasoline. However this incomplete analysis ignores the impact of powertrain efficiency and mass of the powertrain itself. When we compare the potential of battery electric vehicles (BEVs) as an alternative for conventional vehicles, it is important to include the energy in the fuel and their storage as well as the eventual conversion to mechanical energy. For instance, useful work expected out of a conventional vehicle as well as a BEV is the same (to drive 300 miles with a payload of about 300 lb). However, the test weight of a Conventional vehicle and BEV will differ on the basis of what is needed to convert their respective stored energy to mechanical energy.

In response to the stipulations of the Energy Policy and Conservation Act and the global momentum toward carbon mitigation, there has been a pronounced tightening of fuel economy standards for manufacturers. This stricter regulation is coupled with an accelerated transition to electric vehicles, catalyzed by advances in electrification technology and a decline in battery cost. Improvements in the fuel economy of medium- and heavy-duty vehicles through electrification are particularly noteworthy. Estimating the magnitude of fuel economy improvements that result from technological advances in these vehicles is key to effective policymaking. In this research, we generated vehicle models based on assumptions regarding advanced transportation component technologies and powertrains to estimate potential vehicle-level fuel savings. We also developed a systematic approach to evaluating a vehicle’s fuel economy by calibrating the size of the components to satisfy performance requirements.

There is a growing interest in electric and hybrid electric vehicles (EV and HEV) due to their high efficiency and low emission. In EV and HEV, the characteristic of the traction motor is essential for the performance and efficiency of the EV and HEV. In this paper, the advantages of the extended constant power range characteristic of the traction motor for both propulsion and regenerative braking are analyzed. Simulation results are presented to verify the conclusions. Due to its several inherent advantages, especially its capability of having an extended constant power range, Switched Reluctance Motor (SRM) is proposed as the candidate of the traction motor in EV and HEV. The design methodology of SRM for achieving an extended constant power range and the control strategy of SRM for regenerative braking in EV and HEV are presented.

This paper describes a configuration and controller, designed using Autonomie,1 for dual-motor battery electric vehicle (BEV) heavy-duty trucks. Based on the literature and current market research, this model was designed with two electric motors, one on the front axle and the other on the rear axle. A rule-based control algorithm was designed for the new dual-motor BEV, based on the model, and the control parameters were optimized by using a genetic algorithm (GA). The model was simulated in diverse driving cycles and gradeability tests. The results show both a good following of the desired cycle and achievement of truck gradeability performance requirements. The simulation results were compared with those of a single-motor BEV and showed reduced energy consumption with the high-efficiency operation of the two motors.

This paper addresses the fundamental issues faced in the aircraft electrical system architectures. Furthermore, a brief description of the conventional and advanced aircraft power system architectures, their disadvantages, opportunities for improvement, future electric loads, role of power electronics, and present trends in aircraft power system research will be given. Finally, this paper concludes with a brief outline of the projected advancements in the future.

The desirable braking system of a land vehicle is that it can stop the vehicle or reduce the vehicle speed as quickly as possible, maintain the vehicle direction stable and recover kinetic energy of the vehicle as much as possible. In this paper, an electronically controlled braking system for EV and HEV has been proposed, which integrates regenerative braking, automatic control of the braking forces of front and rear wheels and wheels antilock function together. When failure occurs in the electric system, the braking system can function as a conventional man-actuated braking system. Control strategies for controlling the braking forces on front and rear wheels, regenerative braking and mechanical braking forces have been developed. The braking energy that can be potentially recovered in typical driving cycle has been calculated. The antilock performance of the braking system has been simulated.

The US Department of Energy’s Co-Optimization of Engine and Fuels Initiative (Co-Optima) investigated how unique properties of bio-blendstocks considered within Co-Optima help address emissions challenges with mixing controlled compression ignition (i.e., conventional diesel combustion) and enable advanced compression ignition modes suitable for implementation in a diesel engine. Additionally, the potential synergies of these Co-Optima technologies in hybrid vehicle applications in the medium- and heavy-duty sector was also investigated. In this work, vehicles system were simulated using the Autonomie software tool for quantifying the benefits of Co-Optima engine technologies for medium-duty trucks. A Class 6 delivery truck with a 6.7 L diesel engine was used for simulations over representative real-world and certification drive cycles with four different powertrains to investigate fuel economy, criteria emissions, and performance.

Their easy availability, lower well-to-wheel emissions, and relative ease of use with existing engine technologies have made ethanol and ethanol-gasoline blends a viable alternative to gasoline for use in spark-ignition (SI) engines. The lower energy density of ethanol and ethanol-gasoline blends, however, results in higher volumetric fuel consumption compared with gasoline. Also, the higher latent heat of vaporization can result in cold-start issues with higher-level ethanol blends. On the other hand, a higher octane number, which indicates resistance to knock and potentially enables more optimal combustion phasing, results in better engine efficiency, especially at higher loads. This paper compares the fuel consumption and emissions of two ethanol blends (E50 and E85) with those for gasoline when used in conventional (non-hybrid) and power-split-type plug-in hybrid electric vehicles (PHEVs).

This study presents a process to quantify the fuel saving potential of electrified powertrains for medium and heavy duty vehicles. For this study, equivalent vehicles with electrified powertrains are designed with the underlying principle of not compromising on cargo carrying capacity or performance. Several performance characteristics, that are relevant for all types of medium and heavy duty vehicles, were identified for benchmarking based on the feedback from the industry. Start-stop hybrids, parallel pre-transmission hybrids, plug-in hybrids, and battery electric vehicles are the technology choices in this study. This paper uses one vehicle as an example, explains the component sizing process followed for each powertrain, and examines each powertrain’s fuel saving potential. The process put forth in this paper can be used for evaluating vehicles that belong to all medium and heavy duty classes.

Studying the dynamics of electric motor drives is not easy. Indeed, there is no unified approach to model both the mechanical and the electrical elements of the motor drive in order to bring an intuitive understanding of the dynamic behavior. Moreover, for traction purposes, the machines are often used at field-weakening operation, which can be a source of unwanted oscillations. In this paper, the gyrator-based equivalent circuit modeling is presented. The method allows the understanding of some aspects of the dynamic behavior of DC motor drives such as the interaction between electric inductances and the rotor inertia and their oscillating behavior.

The National Highway Traffic Safety Administration (NHTSA) has been leading U.S. efforts related to the rulemaking process for Corporate Average Fuel Economy (CAFE) standards. Argonne National Laboratory, a U.S. Department of Energy (DOE) national laboratory, has developed a full-vehicle simulation tool called Autonomie that has become one of the industry standard tools for analyzing vehicle performance, energy consumption, and technology effectiveness. Through an Interagency Agreement, the DOE Argonne Site Office and Argonne National Laboratory have been tasked with conducting full vehicle simulation to support NHTSA CAFE rulemaking. This paper presents an innovative approach focused on large-scale simulation processes spanning standard regulatory driving cycles, diverse vehicle classes, and various timeframes. A key element of this approach is Autonomie’s capacity to integrate advanced engine technologies tailored to specific vehicle classes and powertrains.

Thermoelectric generators (TEGs) can be used for a variety of applications in automobiles. There is a lot of interest in using them for waste heat recovery from a fuel economy point of view. This paper examines the potential of TEGs to provide cost-effective improvements in the fuel economy of conventional vehicles and hybrid electric vehicles (HEVs). Simulation analysis is used to quantify fuel economy benefits. The paper explains how a TEG is used in a vehicle and explores the idea of improving the TEG design by introducing a thermal reservoir in the TEG model to improve the waste heat recovery. An effort is made to identify the technological and economic barriers (and their thresholds) that could prevent TEGs from becoming an acceptable means of waste heat recovery in automobiles.

The concept of hybrid drive trains was first developed for automobiles. These drive trains allow achieving a minimum fuel consumption by properly matching the driving requirements and the engine characteristics. In this paper the authors analyze the possibility of extending this concept to railway vehicles. Basic hybrid railway vehicles are designed and discussed.

Due to their harsh operating environments, military vehicle drive trains have special requirements. These special requirements are usually represented by hill climbing ability, obstacle negotiation, battlefield cross country travel, hard acceleration, high speed, etc. These special requirements need the vehicle drive train to have a wider torque and speed range characteristics than commercial vehicles. We have proved that larger constant power ratio in electric motor can significantly enhance the vehicle acceleration performance. In other words, for the same acceleration performance, large constant power ratio can minimize the power rating of the traction motor drive, thus minimizing the power rating of the power source (batteries for instance). Actually, extension of the constant power range can also significantly enhance the gradeability, which is crucial for military vehicles.