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Technical Paper

Artificial Neural Network Based Energy Storage System Modeling for Hybrid Electric Vehicles

2000-04-02
2000-01-1564
The modeling of the energy storage system (ESS) of a Hybrid Electric Vehicle (HEV) poses a considerable challenge. The problem is not amenable to physical modeling without simplifying assumptions that compromise the accuracy of such models. An alternative is to build conventional empirical models. Such models, however, are time-consuming to build and are data-intensive. In this paper, we demonstrate the application of an artificial neural network (ANN) to modeling the ESS. The model maps the system's state-of-charge (SOC) and the vehicle's power requirement to the bus voltage and current. We show that ANN models can accurately capture the complex, non-linear correlations accurately. Further, we propose and deploy our new technique, Smart Select, for designing ANN training data.
Technical Paper

Excitation of the Automobile Alternator with the Claw Pole Rotor by Means of Stator Winding

2000-04-02
2000-01-1572
It is known, that the alternator self-excitation is possible at capacitor loading [1]. From this follows, that the alternator excitation by means of capacitors connected to one or several stator windings, as from simple excitation winding is located on a rotor, is possible. In the report the excitation of the automobile alternator with claw pole rotor by means of capacitors connected to stator windings at rotor open excitation circuit is considered. Thus, for comparison the alternator idle characteristics are received both at excitation by means capacitors, and by means of a simple excitation winding. Besides the other electrical parameters of the alternator with claw pole rotor by experimental way are determined. On the basis of the received data the alternator digital model was developed, it takes into account the magnetic circuit saturation, by using of the received experimental idle characteristics.
Technical Paper

Advanced Lithium Solid State Battery Developments

2000-04-02
2000-01-1588
This paper presents a summary of a recent conference entitled Advanced Lithium Solid State Batteries Workshop that was held on July 13–15, 1999. The conference was sponsored by the Department of Energy's Office of Advanced Automotive Technologies, and the Office of Basic Energy Sciences' (BES) Division of Chemical Sciences. This paper presents a summary of the results and recommendations from the conference, including: A review of current research on solid state electrolytes and their interfaces with an emphasis on both applied and basic studies. The research includes theoretical studies of solid polymer electrolytes (SPEs), lithium ion transport in SPEs, and simulations of the electrolyte–cathode interface. Experimental results are presented on ion transport phenomena in SPEs (NMR and X–ray) and mechanical stresses on electrodes, among other topics.
Technical Paper

A Review of Battery Exchange Technology for Refueling of Electric Vehicles

2000-04-02
2000-01-1586
The limited energy storage and long recharge time of electric vehicle batteries have motivated several alternatives to in-vehicle slow charging. Solutions generally fall into three categories: (1) fast charging, in which batteries are charged in-vehicle at an accelerated rate, (2) battery material reloading or refueling, in which the energy-carrying elements of the battery are physically replaced or replenished, and (3) battery interchange, involving the complete exchange of the battery pack, usually with the aid of some semi-automated mechanism. Among these options, the last, battery interchange, has tended to receive the least industry attention, but has been an expansive topic of invention and novel deployment.
Technical Paper

Speed-Sensorless Control of Induction Motors for Electric Vehicles

2000-04-02
2000-01-1603
An electric bus system has been operating in the downtown area of Chattanooga, Tennessee for more than four years. The buses use traditional hard-switched IGBT inverters driving special induction motors with a speed sensor (tachometer) and two embedded flux-sensing windings to provide rotor speed and flux information to the motor controller for implementation of high performance field oriented control (vector control). The induction motor is oil-cooled and equipped with an internal planar gear reduction. The current system has experienced failures in both speed sensors and flux sensors because they are unreliable, susceptible to EMI and must operate in a hostile environment created by oil leaks. A speed- and flux-sensorless induction motor drive system with a new 100 kW soft-switching inverter has been implemented to replace the existing system.
Technical Paper

Advanced Automotive Technologies Energy Storage R&D Programs at the U.S. Department of Energy-Recent Achievements and Current Status

2000-04-02
2000-01-1604
The United States supports an active research and development (R&D) program to develop electric and hybrid vehicle technologies and accelerate their commercialization. The U.S. Department of Energy (DOE), through its Office of Advanced Automotive Technologies (OAAT), supports the development of advanced energy storage and power electronics technologies, fuel cells, advanced direct-injection engines, vehicle systems, lightweight materials, and fuels. Much of this R&D directly supports the Partnership for a New Generation of Vehicles (PNGV), a landmark partnership between the U.S. Federal Government and automakers with the goal of developing a six-passenger family sedan with up to 80 miles per gallon (mpg) fuel economy by 2004. In these efforts, the DOE is working closely with its national laboratories, the auto industry and its suppliers, other government agencies, universities, and innovative small businesses. The Department continues to collaborate closely with the U.S.
Technical Paper

Ovonic Power and Energy Storage Technologies For the Next Generation of Vehicles

2000-04-02
2000-01-1590
The next generation of vehicles will see many new concepts involving propulsion technologies currently being developed by many of the worlds automakers and suppliers. These concepts will include pure electric vehicles (EV), hybrid electric vehicles (HEV) with advanced internal combustion engines and fuel cell hybrid electric vehicles (FCHEV). These new vehicle concepts all need a high-efficiency electrical energy storage system (EESS). This paper describes the basic requirements for the next-generation vehicle technologies and emphasizes the performance of Ovonic technologies as it relates to vehicle requirements. Ovonic Battery Company (OBC) is developing and commercializing enabling technologies for the energy storage for advanced vehicles. Ovonic technologies enable the performance of advanced vehicles to exceed that of today's conventional vehicles while providing additional benefits of clean-air transportation and greatly reduced fuel consumption.
Technical Paper

Government-Industry Partnerships and Environmental and Safety Solutions

2000-04-02
2000-01-1593
The Advanced Battery Readiness Ad Hoc Working Group, a government- industry forum sponsored by the United States Department of Energy, is charged with assessing environmental and safety issues associated with advanced batteries for electric and hybrid electric vehicles. Electric and hybrid electric vehicles require sophisticated advanced battery storage systems. Frequently, toxic, reactive, and flammable substances are used in the energy storage systems. Often, the substances have safety, recycling, and shipping implications with respect to U.S. Environmental Protection Agency and Department of Transportation regulations. To facilitate commercialization, reg-ulations must either be modified or newly developed. Government-industry coordination has expedited needed regulatory changes, and promoted other partnerships to achieve environmental and safety solutions.
Technical Paper

Electrical Characterization of a Dielectric Barrier Discharge Plasma Device

1999-10-25
1999-01-3635
A planar dielectric barrier discharge device has been tested for exhaust emission reduction in simulated engine exhaust. This device's electrical characteristics have been measured and are presented in this paper. The device consists of two dielectric barriers which act like series capacitors, with the gas gap between them. At low gap voltages, the gas gap also acts like a capacitance, with a much smaller capacitance than the barriers. At higher voltages, the gas gap breaks down and a blue–purple glow visually fills the gap. The partially ionized gas conducts charge across the gap, building electrical charge on the dielectric barrier inner surface. When the AC excitation voltage peaks and starts to go toward an opposite polarity, the discharge momentarily extinguishes, trapping charge in the dielectric barrier capacitance.
Technical Paper

Automotive Electrical System in the New Millennium

1999-11-15
1999-01-3747
The automotive industry is investigating the change of electrical system voltage in a vehicle from the present 14 volt (12V battery) to 42 volt (36V battery) to integrate new electrical and electronic features. These new features require more amperes, thicker wires, large power devices, and eventually higher cost. The existing 14V system is very difficult to sustain so much content because of constraints of performance, efficiency, cost, packaging space, and manufacture-ability. This paper discusses foreseeable needs moving to a higher voltage, and reasons of 42V selection. It explores benefits and drawbacks when the voltage is changed from 14V to 42V in the areas of wire harness, power electronics, smart switching, power supply, etc. Finally, two typical 42/14V dual voltage architectures are presented for a likely 42V transition scenario.
Technical Paper

TruCharge™ An Advanced System for Supporting Vehicle Batteries and Eliminating Unscheduled Battery Maintenance

1999-11-15
1999-01-3748
There has been minimal innovation in the area of battery test and diagnostic support over the past 20 years. Battery testing has been limited to measurement of terminal voltage, electrolyte specific gravity measurements and load testing. This paper describes an innovative and newly developed battery analyzer/charger unit. The AlliedSignal TruCharge unit is capable of providing accurate state-of-charge (SOC), capacity as well as providing battery defect data via an automated test sequence that takes less than 20 seconds. It charges the battery quickly while minimizing the generation of hazardous hydrogen gas. The underlying technology is described along with the performance features and specifications of the unit. The unit is also capable of recovering sulfated lead acid batteries. The economic and environmental benefits of battery recovery are discussed. This unit is developed based upon extensive market analysis.
Technical Paper

Alternative Vehicle Power Sources: Towards a Life Cycle Inventory

2000-04-26
2000-01-1478
Three alternatives to internal combustion vehicles currently being researched, developed, and commercialized are electric, hybrid electric, and fuel-cell vehicles. A total life-cycle inventory for an alternative vehicle must include factors such as the impacts of car body materials, tires, and paints. However, these issues are shared with gasoline-powered vehicles; the most significant difference between these vehicles is the power source. This paper focuses on the most distinct and challenging aspect of alternative-fuel vehicles, the power sources. The life-cycle impacts of battery systems for electric and hybrid vehicles are assessed. Less data is publicly available on the fuel cell; however, we offer a preliminary discussion of the environmental issues unique to fuel cells. For each of these alternative vehicles, a primary environmental hurdle is the consumption of materials specific to the power sources.
Technical Paper

Assessing Fuel Cell Power Sustainability

2000-04-26
2000-01-1490
In recent years alternative automobile power technologies have received increased attention from OEM's, special interest groups, and the public. Plausible power technologies now include internal combustion engines, batteries, fuel cells, and a variety of hybrid technologies. The merits of each of these technologies as a means to move personal and fleet transportation into the next century have been highly debated. One technology that has emerged as a viable alternative to the internal combustion engine is the fuel cell. Considering arguments on all sides of the debate, the authors describe the results of a systematic, focused examination of the sustainability of fuel cells for transportation and discuss strategies for sustainable technology design. Sustainable technologies are those that contribute to preserving or improving societal quality, the environment, and the economy for future generations.
Technical Paper

Feasibility of a Solar Powered Re-Deployable Stratospheric LTA Platform

2000-04-26
2000-01-1506
Lighter-Than-Air type stratospheric long duration platforms, now under development, are re-deployable vehicles which play identical roles as artificial satellites except that LTA platforms can be recovered, refit and launched again in case of malfunction and after their lifetime service, all of them can be recovered, unlike satellites resulting in space debris and further atmospheric contamination. These LTA stratospheric platforms can be driven by either solar power or ground-to-air transmitted microwave power. Solar powered platforms are the most environmentally friendly, but need secondary batteries for nighttime propulsion, making vehicle size bigger. This paper presents the feasibility of the solar powered stratospheric platform and its re-deployable processes.
Technical Paper

NanoMet: On-Line Characterization of Nanoparticle Size and Composition

2000-06-19
2000-01-1998
NanoMet is a new technique for on-line characterization of nanoparticle size and composition and their diffusion behavior. NanoMet consists of a pocket size diluter with tunable dilution ratio, a sampling interface for high concentration measurements and two on-line sensors. Simultaneous operation of the two sensors yields both the active surface (corona discharge diffusion charging sensor, DC) and the active surface times material coefficient (photoelectric aerosol sensor, PAS). Division of the readings provides the material coefficient which turns out to be characteristic of the particle source. Thus, information on source and toxicity of the aerosol is obtained. Thanks to the diluter and the sensitivity of the sensors the measurable concentration range stretches from (vehicle) raw emissions to ambient air / occupational exposure measurements. A particle sizing unit with a diffusion battery and a centrifuge is under development. NanoMet measures particles in-situ, i.e. as aerosol.
Technical Paper

Development and In-orbit Performance of a Thermal Control System for Nickel-Cadmium Batteries Based on Loop Heat Pipes

2000-07-10
2000-01-2456
In 1995 TAIS Ltd developed and manufactured a Thermal Control System (TCS) for Nickel-Cadmium Batteries (NCB) based on Loop Heat Pipes (LHP). This TCS was ordered for the Chinese meteorological satellite FY-1C by Shanghai Institute of Spacecraft Engineering. The paper presents results of comparative analysis for some design features of the TCS, thermal vacuum test results, description of TCS layout for the NCB on board the FY-1 C satellite, test results for TSC after its integration into the satellite and flight telemetry data.
Technical Paper

Thermal Control of Mars Lander and Rover Batteries and Electronics Using Loop Heat Pipe and Phase Change Material Thermal Storage Technologies

2000-07-10
2000-01-2403
This paper describes a novel thermal control system for future Mars landers and rovers designed to keep battery temperatures within the −10 °C to +25 °C temperature range. To keep the battery temperatures above the lower limit, the system uses: 1) a phase change material (PCM) thermal storage module to store and release heat and 2) a loop heat pipe (LHP) to transfer heat from a set of Radioisotope Heater Units (RHUs) to the battery. To keep the battery temperature below the upper limit, a thermal control valve in the LHP opens to redirect the working fluid to an external radiator where excess heat is dumped to the atmosphere. The PCM thermal storage module was designed and fabricated using dodecane paraffin wax (melting point, − 9.6 °C) as the phase change material. A miniature ammonia loop heat pipe with two condensers and an integrated thermal control valve was designed and fabricated for use with the PCM thermal storage unit.
Technical Paper

A Miniature Dewpoint Hygrometer for Monitoring Human Environments in Space

2000-07-10
2000-01-2301
Water vapor enjoys unique importance in Earth’s atmosphere and human environments in space. In spite of this importance, humidity measurement remains a difficult technological problem, and no single instrument is optimal for all applications. We have developed and demonstrated a high-sensitivity dewpoint hygrometer in flight tests on a small radiosonde balloon and the NASA DC8. This instrument achieves fast response to atmospheric humidity by using a surface acoustic wave (SAW) device to detect condensation with much higher sensitivity than conventional optical dew detectors. An early prototype showed more than an order of magnitude faster response than chilled-mirror hygrometers in tropospheric humidity measurements on the NASA DC8. For the radiosonde experiment, we miniaturized and integrated the SAW hygrometer into a 1 kg package that includes pressure and temperature sensors, GPS, a programmable instrument controller, a high-speed radio modem, and lithium-ion batteries.
Technical Paper

Power Down Analysis for the Hubble Space Telescope Power Control Unit Replacement

2001-07-09
2001-01-2217
During the fourth servicing mission (SM3B) of the Hubble Space Telescope (HST), the Power Control Unit (PCU) will be replaced to correct a fault that has appeared. The PCU controls the power from the solar arrays and the batteries to the entire telescope. The fault reduces the amount of battery power available and could result in a limit being placed on power usage in the future thereby seriously reducing science capability. Because all power goes through the PCU, power will be cut off to all HST components for the duration of the change out. Since the maximum Extra Vehicular Activity (EVA) duration capability for the Orbiter Astronauts is eight hours, a thermal analysis was conducted to evaluate the effect of an eight-hour power off period on the HST components. This analysis was conducted using the HST servicing mission thermal timeline FORTRAN code and the Lockheed Martin proprietary code THERM.
Technical Paper

A Cooling System for the EAPU Shuttle Upgrade

2001-07-09
2001-01-2152
The Shuttle orbiter currently uses hydrazine-powered APU’s for powering its hydraulic system pumps. To enhance vehicle safety and reliability, NASA is pursuing an APU upgrade where the hydrazine-powered turbine is replaced by an electric motor pump and battery power supply. This EAPU (Electric APU) upgrade presents several thermal control challenges, most notably the new requirement for moderate temperature control of high-power electronics at 132 °F (55.6 °C). This paper describes how the existing Water Spray Boiler (WSB), which currently cools the hydraulic fluid and APU lubrication oil, is being modified to provide EAPU thermal management.
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