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Electric Vehicles (electric + vehicle)

Distribution by Scientific Domains

Engineering	55%
Polymers and Materials Science	22%
Business, Economics, Finance and Accounting	16%

Kinds of Electric Vehicles

hybrid electric vehicle

Selected Abstracts

Optimal design of an induction motor for an electric vehicle

EUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 1 2006
Jawad Faiz
Abstract In this paper a squirrel-cage three-phase induction motor, selected as the driving power of an electric vehicle (EV), is designed optimally using a modified-Hooke,Jeeves optimization technique. The optimal designs are analyzed and compared with varying pole number, rated base speed and slot shapes. This optimization technique has the same advantages such as simple programming, non-gradient, short convergence time and independent variation of each parameter. Variation of design parameters of optimally designed motors versus rated base speed for 2- and 4-pole motors are presented and discussed. The results show that a 2-pole motor with parallel-sided stator and rotor slots and rated speed 1800,rpm has the best performance. Copyright © 2005 John Wiley & Sons, Ltd. [source]

Fuzzy torque distribution control for a parallel hybrid vehicle

EXPERT SYSTEMS, Issue 1 2002
Jong-Seob Won
A fuzzy torque distribution controller for energy management (and emission control) of a parallel hybrid electric vehicle is proposed. The proposed controller is implemented in terms of a hierarchical architecture which incorporates the mode of operation of the vehicle as well as empirical knowledge of energy flow in each mode. Moreover, the rule set for each mode of operation of the vehicle is designed in view of an overall energy management strategy that ranges from maximal emphasis on battery charge sustenance to complete reliance on the electrical power source. The proposed control system is evaluated via computational simulations under the FTP75 urban drive cycle. Simulation results reveal that the proposed fuzzy torque distribution strategy is effective over the entire operating range of the vehicle in terms of performance, fuel economy and emissions. [source]

Implications of system expansion for the assessment of well-to-wheel CO2 emissions from biomass-based transportation

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 13 2010
Elisabeth Wetterlund
Abstract In this paper we show the effects of expanding the system when evaluating well-to-wheel (WTW) CO2 emissions for biomass-based transportation, to include the systems surrounding the biomass conversion system. Four different cases are considered: DME via black liquor gasification (BLG), methanol via gasification of solid biomass, lignocellulosic ethanol and electricity from a biomass integrated gasification combined cycle (BIGCC) used in a battery-powered electric vehicle (BPEV). All four cases are considered with as well as without carbon capture and storage (CCS). System expansion is used consistently for all flows. The results are compared with results from a conventional WTW study that only uses system expansion for certain co-product flows. It is shown that when expanding the system, biomass-based transportation does not necessarily contribute to decreased CO2 emissions and the results from this study in general indicate considerably lower CO2 mitigation potential than do the results from the conventional study used for comparison. It is shown that of particular importance are assumptions regarding future biomass use, as by expanding the system, future competition for biomass feedstock can be taken into account by assuming an alternative biomass usage. Assumptions regarding other surrounding systems, such as the transportation and the electricity systems are also shown to be of significance. Of the four studied cases without CCS, BIGCC with the electricity used in a BPEV is the only case that consistently shows a potential for CO2 reduction when alternative use of biomass is considered. Inclusion of CCS is not a guarantee for achieving CO2 reduction, and in general the system effects are equivalent or larger than the effects of CCS. DME from BLG generally shows the highest CO2 emission reduction potential for the biofuel cases. However, neither of these options for biomass-based transportation can alone meet the needs of the transport sector. Therefore, a broader palette of solutions, including different production routes, different fuels and possibly also CCS, will be needed. Copyright © 2009 John Wiley & Sons, Ltd. [source]

Shortest path stochastic control for hybrid electric vehicles

INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 14 2008
Edward Dean Tate Jr
Abstract When a hybrid electric vehicle (HEV) is certified for emissions and fuel economy, its power management system must be charge sustaining over the drive cycle, meaning that the battery state of charge (SOC) must be at least as high at the end of the test as it was at the beginning of the test. During the test cycle, the power management system is free to vary the battery SOC so as to minimize a weighted combination of fuel consumption and exhaust emissions. This paper argues that shortest path stochastic dynamic programming (SP-SDP) offers a more natural formulation of the optimal control problem associated with the design of the power management system because it allows deviations of battery SOC from a desired setpoint to be penalized only at key off. This method is illustrated on a parallel hybrid electric truck model that had previously been analyzed using infinite-horizon stochastic dynamic programming with discounted future cost. Both formulations of the optimization problem yield a time-invariant causal state-feedback controller that can be directly implemented on the vehicle. The advantages of the shortest path formulation include that a single tuning parameter is needed to trade off fuel economy and emissions versus battery SOC deviation, as compared with two parameters in the discounted, infinite-horizon case, and for the same level of complexity as a discounted future-cost controller, the shortest-path controller demonstrates better fuel and emission minimization while also achieving better SOC control when the vehicle is turned off. Linear programming is used to solve both stochastic dynamic programs. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Integrated control method for a fuel cell hybrid system

ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2009
Hongwen He
Abstract To apply a fuel cell engine (FCE) on a hybrid electric vehicle, an integrated control method is put forward according to the driving characteristics of the vehicle. The FCE's output power is self-regulated to minimize hydrogen consumption and at the same time to meet the driving power requirement of the vehicle. For the difference of the power output dynamics, the actual power difference between the FCE and the vehicle load is compensated passively by a secondary power battery pack. Vehicle experiments show that the fuel cell hybrid system works well without any adverse influence on the vehicle power performance. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd. [source]

Design and Synthesis of Hierarchical Nanowire Composites for Electrochemical Energy Storage

ADVANCED FUNCTIONAL MATERIALS, Issue 21 2009
Zheng Chen
Abstract Nanocomposites of interpenetrating carbon nanotubes and vanadium pentoxide (V2O5) nanowires networks are synthesized via a simple in situ hydrothermal process. These fibrous nanocomposites are hierarchically porous with high surface area and good electric conductivity, which makes them excellent material candidates for supercapacitors with high energy density and power density. Nanocomposites with a capacitance up to 440 and 200,F g,1 are achieved at current densities of 0.25 and 10 A g,1, respectively. Asymmetric devices based on these nanocomposites and aqueous electrolyte exhibit an excellent charge/discharge capability, and high energy densities of 16,W h kg,1 at a power density of 75,W kg,1 and 5.5,W h kg,1 at a high power density of 3,750,W kg,1. This performance is a significant improvement over current electrochemical capacitors and is highly competetive with Ni,MH batteries. This work provides a new platform for high-density electrical-energy storage for electric vehicles and other applications. [source]

Aliovalent Doping for Improved Battery Performance: Aliovalent Substitutions in Olivine Lithium Iron Phosphate and Impact on Structure and Properties (Adv. Funct.

ADVANCED FUNCTIONAL MATERIALS, Issue 7 2009
Mater.
Lithium metal phosphate olivines have emerged as important storage electrodes in batteries for electric vehicles and other applications addressing global issues of energy supply and climate change. On page 1060, Meethong et al. use controlled aliovalent solute doping to tailor the defect and atomic structure in olivines, and demonstrate the resulting impact on physical and electrochemical properties. [source]

Aliovalent Substitutions in Olivine Lithium Iron Phosphate and Impact on Structure and Properties

ADVANCED FUNCTIONAL MATERIALS, Issue 7 2009
Nonglak Meethong
Abstract Lithium transition metal phosphate olivines are enabling a new generation of high power, thermally stable, long-life rechargeable lithium batteries that may prove instrumental in the worldwide effort to develop cleaner and more sustainable energy. Nanoscale (<100,nm) derivatives of the olivine family LiMPO4 (M,=,Fe, Mn, Co, Ni) are being adopted in applications ranging in size scale from hybrid and plug-in hybrid electric vehicles to utilities-scale power regulation. Following the previous paradigm set with intercalation oxides, most studies have focused on the pure ordered compounds and isovalent substitutions. In contrast, even the possibility for, and role of, aliovalent doping has been widely debated. Here, critical tests of plausible defect compensation mechanisms using compositions designed to accommodate Mg2+, Al3+, Zr4+, Nb5+ ions on the M1,and/or M2 sites of LiFePO4 with appropriate charge-compensating defects are carried out, and conclusive crystallographic evidence for lattice doping, e.g., up to at least 12 atomic percent added Zr, is obtained. Structural and electrochemical analyses show that doping can reduce the lithium miscibility gap, increase phase transformation kinetics during cycling, and expand Li diffusion channels in the structure. Aliovalent modifications may be effective for introducing controlled atomic disorder into the ordered olivine structure to improve battery performance. [source]

Lithium-Ion Batteries: Nanostructured Fe3O4/SWNT Electrode: Binder-Free and High-Rate Li-Ion Anode (Adv. Mater.

ADVANCED MATERIALS, Issue 20 2010
20/2010)
A flexible carbon nanotube net is employed to demonstrate high capacity/high volume expansion materials for Li-ion battery electrodes, as presented by A. C. Dillon et al. on page E145. An electrode, with well over twice the capacity of the state-of-the-art technology, charges and discharges in 12 minutes without significant capacity fade. These advancements, funded by the US Department of Energy, Office of Vehicle Technologies Program, will help enable next generation electric vehicles. [source]

Methods to control wheel locks and wheel spins on low friction coefficient roads for front and rear wheel independent drive type electric vehicles (FRID EVs)

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 2 2009
Nobuyoshi Mutoh Member
Abstract Wheel lock and spin control methods suitable for front and rear wheel independent drive type electric vehicles (FRID EVs) are studied here. Wheel locks and spins occur easily when braking and driving operations such as deceleration and acceleration are performed on bad roads with low friction coefficient such as wet or frozen roads. The methods studied here are characterized by using the structural feature of FRID EVs which can freely distribute the driving and braking torques to front and rear wheels according to running and road surface conditions. These wheel locks and spins occurring when braking and driving on bad roads are controlled by properly distributing the braking and driving torques to front and rear wheels in consideration of the load movement caused by braking operations and slip ratios of the front and rear wheel sides. The effectiveness of the wheel lock and spin methods studied here is verified through simulations and experiments on various roads with a low friction coefficient using a prototype EV with the FRID structure. Copyright © 2009 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

Energy Saving and Environmental Measures in Railway Technologies: Example with Hybrid Electric Railway Vehicles

IEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 1 2008
Masamichi Ogasa Member
Abstract The electric railway system is the highest class of energy efficient transportation means. This is due to two important points: (i) low running resistance (including low energy losses) and (ii) energy regeneration in braking. Regenerative braking of railway electric vehicles is effective when the other powering ones, in other words electrical load, exist near the regenerating train on the same electrified line. So, early in the morning and at midnight, or in the low-density district lines, regeneration cancellation phenomenon often occurs and the regenerative brake force cannot be operated in accordance with the recommended value. Newly appeared high-performance energy storage devices press the issues of energy storage and reuse technologies on ground and on vehicles. Hybrid energy source is one effective solution. In this paper, as an example, we show our trolley and on-board battery hybrid controlled tramcar, developed to reduce regeneration cancellation. With the trolley line collective power as well as charge and discharge power of the on-board lithium ion rechargeable battery, the hybrid energy providing and regenerating technology is achieved. The running test results show a maximum regenerative ratio of 44%, which is top class value in an electric railway system. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source]

Natural gas internal combustion engine hybrid passenger vehicle

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 7 2008
S. Wright
Abstract The implementation of hybrid electric vehicles powered with alternative fuels is critical in reducing national dependence on imported crude oil, addressing the detrimental environmental impact of increasing petroleum usage worldwide, and sustaining the national economy. The question is not whether changes should be made, but instead centers on identifying pathways that will lead to the greatest environmental and economic benefits. To avoid misuse of limited infrastructure investment, the objective of this research is to consider a broad range of relevant factors to determine desirable power plant,fuel combinations for hybrid electric vehicles. In the long term, fuel cells may dominate this application, but at least in the short term, proton exchange membrane fuel cells (PEMFCs) will not likely offer immediate substantial benefit over internal combustion (IC) engines. Environmentally friendly operation of the PEMFC results partly due to low-temperature operation but primarily due to the requirement of a clean fuel, hydrogen. In addition, the differential benefits from power plant choice can be overshadowed by the advantages obtained from hybrid electric vehicle technology and alternative fuels. Consequently, the fuel flexibility of IC engines provides an advantage over the relatively fuel inflexible PEMFC. The methane/hythane IC engine hybrid option, as developed and presented here, is a promising pathway that avoids the barriers encountered with conventional non-hybrid natural gas vehicles, namely range, power and fueling infrastructure difficulties. Dynamometer testing of the natural gas hybrid prototype on the certification FTP-72 duty cycle revealed very low emissions and mileage greater than 33 miles per gallon gasoline equivalent. This hybrid option utilizes a domestic, cost-effective fuel with renewable sources. With multi-fuel capability (methane, hythane and gasoline) it is also designed for use within the emerging hydrogen market. This hybrid option offers reliability and cost-effective technology with immediate wide spread market availability. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Shortest path stochastic control for hybrid electric vehicles

Constructing a cognition map of alternative fuel vehicles using the DEMATEL method

JOURNAL OF MULTI CRITERIA DECISION ANALYSIS, Issue 1-2 2009
Cheng-Wei Lin
Abstract Environmental protection has taken serious notice of global warming. The Intergovernmental Panel on Climate Change (IPCC) has proved that CO2 is one of the factors for global warming. Furthermore, the majority of this emission comes from the vehicles using petroleum fuels. For this reason, alternative fuels become a very popular issue. There are many automakers and researchers endeavoring to develop alternative fuel vehicles (AFVs). There already have been many types of alternative fuels used in vehicles, such as electric vehicles (EVs), hybrid electric vehicles (HEVs), fuel cell (hydrogen) vehicles, natural gas vehicles (CNG), methanol vehicles, ethanol vehicles, and bio-diesel vehicles, etc. Different types of the alternative fuels have different characteristics to which attention should be paid. It is difficult for users to identify which one is the best choice for them to use. This problem concerns the characteristics of each alternative fuel. A lot of criteria and aspects related to the alternative fuels should be considered at the same time. In this study, we try to apply the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method to deal with the importance and causal relationships among the evaluation factors of AFVs. Results show the top three critical evaluation criteria are ,new car cost', ,cruising range', and ,fuel efficiency'; ,air pollution' is the key cause factor influencing others; and ,cruising range' is the key effect factor influenced by others. It is no accident that cost is the most critical factor for users. Consequently, it is suggested to automakers and researchers to carefully analyze the characteristics of each alternative fuel. Fuel efficiency is not only focused on by users, but also it will affect the cruising range. Air pollution is what users care about, so even zero-emission vehicles (ZEVs), which cost more but have lower emission and higher fuel efficiency, could be accepted. There seems to be no perfect AFV, but to endeavor on ZEVs will reduce some disadvantages. Copyright © 2010 John Wiley & Sons, Ltd. [source]

Radical innovation in a small firm: a hybrid electric vehicle development project at Volvo Cars

R & D MANAGEMENT, Issue 4 2010
Hans Pohl
The potential paradigmatic shift in technology from the internal combustion engine to electric propulsion via hybrid electric vehicles (HEVs) has been addressed by most automakers, and has produced very different outcomes. This paper uses the framework of core capabilities to discuss how the small automaker, Volvo Cars, made substantial progress in its HEV development using an approach based on limited resources and a low risk. A comparison with Toyota's successful but very resource-demanding Prius project reveals some factors contributing towards rapid development in a context of limited resources, including focused project objectives, tight collaboration with suppliers of the new technologies, reuse of existing technologies and an unaggressive, bottom-up approach to change the firm's values and norms and other core capability dimensions. This paper provides an empirical illustration of how a small company in a mature industry worked with radical innovation in a development project drawing on the combination of organizational slack, entrepreneurial employees and an extensive use of external (knowledge) suppliers. [source]