Showing papers on "Electric vehicle published in 2001"

Modern Electric Vehicle Technology

Abstract: 1. Engineering Philosophy of EV Developments 2. EV and HEV Developments 3. EV Systems 4. HEV Systems 5. Electric Propulsion 6. Energy Sources 7. EV Auxiliaries 8. EV Simulation 9. EV Infrastructure 10. Energy, environment and economy

Strategy to use an on-board navigation system for electric and hybrid electric vehicle energy management

Abstract: The present invention integrates an on-board navigation system to provide energy management for an electric vehicle (EV) and a hybrid electric vehicle (HEV). The HEV control strategy of the present invention accommodates the goals of fuel economy while always meeting driver demand for power and maintaining the functionality of the traction motor battery system using battery parameter controllers. In the preferred embodiment of the present strategy, a vehicle system controller tightly integrates the navigation system information with energy management while en route to a known destination. Present vehicle location is continuously monitored, expectations of driver demand are determined, and vehicle accommodations are made. The system can be configured to includes as part of its present vehicle location data on road patterns, geography with date and time, altitude changes, speed limits, driving patterns of a vehicle driver, and weather. The vehicle accommodations can be configured to use discrete control laws, fuzzy logic, or neural networks.

Nonconventional on-board charger for electric vehicle propulsion batteries

Abstract: Electric vehicles (EVs) are needed in densely populated urban areas to reduce air pollution. Battery chargers are needed to supply DC voltage to charge the high-energy battery parks used in EVs. This paper deals with an on-board battery charger arrangement that is fully based on the use of the power components of the EV motor drive. Desired features for EV battery chargers such as minimum volume, low cost, high efficiency, and high reliability are fully matched by means of the proposed solution. The proposed on-board charger arrangement has been installed on an electric scooter prototype being developed for the Far East markets. Design analysis and experimental results of the on-board charger prototype are presented.

Temperature-Dependent Battery Models for High-Power Lithium-Ion Batteries

Abstract: In this study, two battery models for a high-power lithium ion (Li-Ion) cell were compared for their use in hybrid electric vehicle simulations in support of the U.S. Department of Energy's Hybrid Electric Vehicle Program. Saft America developed the high-power Li-Ion cells as part of the U.S. Advanced Battery Consortium/U.S. Partnership for a New Generation of Vehicles programs. Based on test data, the National Renewable Energy Laboratory (NREL) developed a resistive equivalent circuit battery model for comparison with a 2-capacitance battery model from Saft. The Advanced Vehicle Simulator (ADVISOR) was used to compare the predictions of the two models over two different power cycles. The two models were also compared to and validated with experimental data for a US06 driving cycle. The experimental voltages on the US06 power cycle fell between the NREL resistive model and Saft capacitance model predictions. Generally, the predictions of the two models were reasonably close to th e experimental results; the capacitance model showed slightly better performance. Both battery models of high-power Li-Ion cells could be used in ADVISOR with confidence as accurate battery behavior is maintained during vehicle simulations.

An analysis of the retail and lifecycle cost of battery-powered electric vehicles

Abstract: Regulators, policy analysts, automobile manufacturers, environmental groups, and others are debating the merits of policies regarding the development and use of battery-powered electric vehicles (BPEVs). At the crux of this debate is lifecycle cost: the annualized initial vehicle cost, plus annual operating and maintenance costs, plus battery replacement costs. To address this issue of cost, we have developed a detailed model of the performance, energy use, manufacturing costs, retail costs, and lifecycle cost of electric vehicles and comparable gasoline internal-combustion engine vehicles (ICEVs). This effort is an improvement over most previous studies of electric vehicle costs because instead of assuming important parameter values for such variables as vehicle efficiency and battery costs, we model these values in detail. We find that in order for electric vehicles to be cost-competitive with gasoline ICEVs, batteries must have a lower manufacturing cost, and a longer life, than the best lithium-ion and nickel-metal hydride batteries we modeled. We believe that it is most important to reduce the battery manufacturing cost to $100/kWh or less, attain a cycle life of 1200 or more and a calendar life of 12 years or more, and aim for a specific energy of around 100 Wh/kg.

Integrated, Feed-Forward Hybrid Electric Vehicle Simulation in SIMULINK and its Use for Power Management Studies

Abstract: A hybrid electric vehicle simulation tool (HE-VESIM) has been developed at the Automotive Research Center of the University of Michigan to study the fuel economy potential of hybrid military/civilian trucks. In this paper, the fundamental architecture of the feed-forward parallel hybrid-electric vehicle system is described, together with dynamic equations and basic features of sub-system modules. Two vehicle-level power management control algorithms are assessed, a rule-based algorithm, which mainly explores engine efficiency in an intuitive manner, and a dynamic-programming optimization algorithm. Simulation results over the urban driving cycle demonstrate the potential of the selected hybrid system to significantly improve vehicle fuel economy, the improvement being greater when the dynamicprogramming power management algorithm is applied.

Yaw-moment control of electric vehicle for improving handling and stability

Abstract: This paper investigates the use of direct yaw moment control by driving or braking forces distribution for improving handling and stability of electric vehicle. Based on its structural merit that electric motors are connected directly to the tires, the implementation of such a control system is expected to achieve satisfactory control performance. Fundamentally the structure of control system is model matching controller which makes the vehicle follow the desired dynamic model by side slip angle regulating feedforward and the state feedback of both yaw rate and side slip angle. Various computer simulations are carried out to verify the effectiveness of the control system. It is clarified that the handling and stability of electric vehicle is improved and the control system still maintain satisfactory control performance despite the change of road surface condition.

The electric car: development and future of battery, hybrid and fuel-cell cars

Abstract: This book covers the development of electric cars, from their early days, to new hybrid models in production. Most of the coverage is focused on the very latest technological issues faced by automotive engineers working on electric cars, as well as the key business factors vital for the successful transfer of electric cars into the mass market.

Regenerative electric vehicle

Abstract: The present invention 10 discloses an automobile having an electric motor 30 along with various means of regenerating auxiliary power for the vehicle. Multiple auxiliary generation means are disclosed including wind generators 26, steam turbines 46, wheel generators 22, brake activated generators 44, and solar t-tops 16. The wind generators are incorporated internal the air duct 24 which passes entirely through the automobile having either roll cage generators 26 or fan type impellers 78 and including means for the air to cool motor 30. Wheel generators 22 are disclosed which may operate off the hubs 22 or have an alternate generator position 28 which places a rotor head in communication with the wheel/tire 34. A steam turbine 46 is disclosed having means to fire 60 a boiler wherein steam 64 is generated which steam drives the steam turbine 46 which in turn has means 66 for driving the generators 68 and thereafter the steam is condensed and recycled through conduit 54 back into the boiler 58. The solar panel t-tops 16 comprise solar membranes 75 which are embedded in the t-tops. Alternatively, an air duct intake port can be tubular shaped 76 instead of rectangular shaped. Also disclosed is an alternative embodiment wherein dual wind turbine generators 25 are incorporated into the down draft system of a Formula 1 racing car.

Life cycle model of alternative fuel vehicles: emissions, energy, and cost trade-offs

Abstract: This paper describes a life cycle model for performing level-playing field comparisons of the emissions, costs, and energy efficiency trade-offs of alternative fuel vehicles (AFV) through the fuel production chain and over a vehicle lifetime. The model is an improvement over previous models because it includes the full life cycle of the fuels and vehicles, free of the distorting effects of taxes or differential incentives. This spreadsheet model permits rapid analyses of scenarios in plots of trade-off curves or efficiency frontiers, for a wide range of alternatives with current and future prices and levels of technology. The model is available on request. The analyses indicate that reformulated gasoline (RFG) currently has the best overall performance for its low cost, and should be the priority alternative fuel for polluted regions. Liquid fuels based on natural gas, M100 or M85, may be the next option by providing good overall performance at low cost and easy compatibility with mainstream fuel distribution systems. Longer term, electric drive vehicles using liquid hydrocarbons in fuel cells may offer large emissions and energy savings at a competitive cost. Natural gas and battery electric vehicles may prove economically feasible at reducing emissions and petroleum consumption in niches determined by the unique characteristics of those systems.

Apparatus for controlling hybrid electric vehicle

Abstract: An apparatus is provided for controlling a hybrid electric vehicle in which a rechargeable battery is discharged to drive an electric motor to cause the hybrid electric vehicle to travel, and the rechargeable battery is charged with regenerative electric power from the electric motor. The apparatus comprises a car navigation apparatus for outputting route information on a route to a destination of the vehicle including height information, and a control section for controlling charging and discharging of the rechargeable battery. The control section controls high discharge without power assist limit to the vehicle in the route before a downhill travel path of the route based on the route information output from the car navigation apparatus.

Method for stopping an engine in a parallel hybrid electric vehicle

Abstract: The invention provides a strategy to stop a parallel HEV powertrain engine while maintaining smooth vehicle response to driver demand using the motor while simultaneously opening an engine disconnect clutch. In the preferred embodiment, the strategy stops an engine (based on, for example, driver demand), disconnects the disconnect clutch to the powertrain, halts fuel to the engine, and predicts a desired motor/generator speed. The prediction of desired motor/generator speed can be: a trajectory comparison based on present and past vehicle velocity and deceleration or on a vehicle accelerator position, or a determination of whether the vehicle is in speed following control mode. The system can also add additional strategies such as accelerate the strategy if a vehicle brake is applied. The gradual takeover by the motor occurs by proportionally decreasing actual engine torque until engine torque is zero while maintaining vehicle velocity using for example a proportional plus integral controller.

Lightweight Electric/Hybrid Vehicle Design

Abstract: This book, intended for automotive engineering students and professionals, covers the particular automotive design approach required for hybrid/electrical drive vehicles. It responds to the world-wide current interest in these technologies in relation to pollution control and conserving oil resources. The radically different design of these vehicles requires a completely different approach to automotive engineering including weight removal in the mechanical systems. Electric hybrid drive and energy storage systems are reviewed.

Dynamic Modeling and Analysis of a Four Motorized Wheels Electric Vehicle

Abstract: A comprehensive dynamic model of a four motorized wheels electric vehicle has been developed and different types of motor control laws were addressed. The first part of this study deals with the full description of the model scope in which the structure of the model, including the sub-models, has been expressed. Subsequently, the sub-models including the tire sub-model, the body motion, and the motor dynamics are fully investigated, and with the use of simulink software, the computer model of the vehicle is simulated. Finally, the motor control laws are presented and the vehicle dynamic behavior studied under different driving conditions. Detailed analyses and comparison of the simulation results are carried out.

Regeneration control device of hybrid electric vehicle

Abstract: A regeneration control device of a hybrid electric vehicle can sufficiently charge a battery with power regenerated as a result of the regenerative braking and effectively perform the regenerative braking, and which can also ease the burden of a friction brake. If chargeable power set by a chargeable power setting device according to an actual level of the battery becomes lower than regenerated power computed by a regenerated power computing unit during the regenerating operation of a motor, the power regenerated by the motor is supplied to a generator. This drives the generator to cause an engine to run an engine brake without the supply of fuel.

Hybrid electric vehicle and method of selectively operating the hybrid electric vehicle

Abstract: A series type hybrid electric vehicle that controls an internal combustion engine, generator, and electric motor for reducing the load applied to the internal combustion engine when the internal combustion engine is restarted, lowers the thermal stresses to the internal combustion engine when the engine is turned off and is able to remove excess fuel when turning off the internal combustion engine.

Hybrid electric vehicle DC power generation system

Abstract: A hybrid electric vehicle, such as a bus or delivery vehicle, includes batteries and a turbogenerator/motor connected through a double conversion control system. The batteries and the turbogenerator/motor are each connected to a DC bus through bi-directional power converters operating as customized bi-directional switching converters configured, under the control of a power controller, to provide an interface between the DC bus and the batteries and turbogenerator/motor, respectively.

Techniques for estimating the residual range of an electric vehicle

Abstract: This paper presents an algorithm that has been developed to estimate the residual range of an electric vehicle, i.e., the distance that can still be covered with the energy stored inside the battery. The algorithm takes into account the complexity of the behavior of electrochemical batteries, with special reference to lead-acid batteries, as well as the main issues related to different driving styles. This paper also discusses some of the experimental results obtained by the use of the algorithm in several urban test trips made using two different types of electric vehicles.

An appraisal of electric automobile power sources

Abstract: Road transportation, as an important requirement of modern society, is presently hindered by restrictions in emission legislations as well as the availability of petroleum fuels, and as a consequence, the fuel cost. For nearly 270 years, we burned our fossil cache and have come to within a generation of exhausting the liquid part of it. Besides, to reduce the greenhouse gases, and to obey the environmental laws of most countries, it would be necessary to replace a significant number of the petroleum-fueled internal-combustion-engine vehicles (ICEVs) with electric cars in the near future. In this article, we briefly describe the merits and demerits of various proposed electrochemical systems for electric cars, namely the storage batteries, fuel cells and electrochemical supercapacitors, and determine the power and energy requirements of a modern car. We conclude that a viable electric car could be operated with a 50 kW polymer-electrolyte fuel cell stack to provide power for cruising and climbing, coupled in parallel with a 30 kW supercapacitor and/or battery bank to deliver additional short-term burst-power during acceleration.

Regeneration control of particulate filter, particularly in a hybrid electric vehicle

Abstract: A method for regeneration of particulate filters or traps in the context of a hybrid electric vehicle includes the step of measuring the back pressure of the filter, and adjusting the engine parameters when the back pressure exceeds a particular value to increase the exhaust temperature, to aid in regeneration. In one mode, the engine speed and engine load are both reset toward particular target values. In another version in which the engine load includes an energy storage device such as a battery, increasing the load includes the step of increasing the battery charge level setpoint. Additionally, for those situations in which the battery cannot accept more charge, a power-dissipating resistor is coupled to an electric source to increase the load. In yet another version, the use of the electrical resistor is made dependent upon the temperature of the filter during regeneration.

A hybrid electric vehicle having a selective zero emission mode, and method of selectively operating the zero emission mode

Abstract: A series type hybrid electric vehicle that controls an internal combustion engine, generator, and electric motor for zero emissions within a zero emission zone. As the vehicle approaches the zero emission zone, the internal combustion engine and generator increase the electrical charge of the battery array to a predetermined level. The internal combustion engine and generator are eventually turned off to prevent emissions from entering the zero emission zone. As the vehicle leaves the zero emission zone, the internal combustion engine and generator are warmed to a predetermined level for a full capacity operation. When the internal combustion engine and generator reach the predetermined level, they operate at full capacity to bring the electrical charge of the battery array to a predetermined electrical level.

Analysis Tool for Fuel Cell Vehicle Hardware and Software (Controls) with an Application to Fuel Economy Comparisons of Alternative System Designs

Abstract: In the area of analysis, a modeling tool for fuel cell vehicles needs to address the transient dynamic interaction between the electric drive train and the fuel cell system. Especially for vehicles lacking an instantaneously responding on-board fuel processor, this interaction is very different from the interaction between a battery (as power source) and an electric drive train in an electric vehicle design. Non-transient modeling leads to inaccurate predictions of vehicle performance and fuel consumption. Applied in the area of development, the existing programs do not support the employment of newer techniques, such as rapid prototyping. This is because the program structure merges control algorithms and component models, or different control algorithms are lumped together in one single control block and not assigned to individual components as they are in real vehicles. In both cases, the transfer of control algorithms from the model into existing hardware is not possible. The simulation program developed in this dissertation recognizes the dynamic interaction between fuel cell system, drive train and optional additional energy storage. It provides models for four different fuel cell vehicle topologies: 1) A load following fuel cell vehicle; 2) A battery hybrid fuel cell vehicle; 3) An ultra-capacitor hybrid fuel cell vehicle in which the ultra-capacitor unit is coupled via a dc-dc converter to the stack; 4) An ultra-capacitor hybrid fuel cell vehicle with direct coupling between fuel cell stack and ultra-capacitor. The structure of the model is a causal and forward-looking. The model separates the modeling of control algorithms from the component models. The setup is strictly modular and encourages the use of rapid prototyping techniques in the development process. The first half of the dissertation explains the model setup. In the second half of the dissertation, the simulation of different hybrid vehicle designs illustrates the capabilities of the model.

Metal resource constraints for electric-vehicle batteries

Abstract: We estimate at what size electric-vehicle stocks could become constrained by metal availability by assessing metal requirement and availability for nine types of batteries: Li-polymer(V), Li-ion(Mn, Ni and Co), NaNiCl, NiMH(AB2 and AB5), NiCd and PbA, that contain seven potentially scarce metals/group of metals: lithium, nickel, cobalt, vanadium, cadmium, lead and rare-earth elements. We assess metal intensities (kg/kW h), battery energy capacities per vehicle (kWh/vehicle), losses in recycling and manufacturing, stocks of available resources, constraints on annual mine production and competition for metals. With pessimistic assumptions for all parameters the material-constrained stocks of battery electric vehicles range from 1.1 million NiCd-battery vehicles to 350 million NaNiCl-battery vehicles. Optimistic assumptions result in estimates between 49 million (NiCd) and 12 000 million (Li-ion(Mn)) vehicles. The corresponding figures for hybrid electric vehicles are typically a factor of 10 higher. Critical factors that affect the outcome are identified.