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Technical Paper

0D-1D Coupling for an Integrated Fuel Economy Control Strategy for a Hybrid Electric Bus

2011-09-11
2011-24-0083
Hybrid electric vehicles (HEVs) are worldwide recognized as one of the best and most immediate opportunities to solve the problems of fuel consumption, pollutant emissions and fossil fuels depletion, thanks to the high reliability of engines and the high efficiencies of motors. Moreover, as transport policy is becoming day by day stricter all over the world, moving people or goods efficiently and cheaply is the goal that all the main automobile manufacturers are trying to reach. In this context, the municipalities are performing their own action plans for public transport and the efforts in realizing high efficiency hybrid electric buses, could be supported by the local policies. For these reasons, the authors intend to propose an efficient control strategy for a hybrid electric bus, with a series architecture for the power-train.
Technical Paper

1000 kW Sodium-Sulfur Battery Pilot Plant: Its Operation Experience at Tatsumi Test Facility

1992-08-03
929055
Since 1978, the Agency of Industrial Science and Technology (AIST) of MITI has promoted research and development of “Large-Scale Energy Conservation Technology” popularly known as the “Moonlight Project”. As the first step, “system technology tests” using improved lead acid batteries started at Kansai Electric's Tatsumi Electric Energy Storage System Test Plant on October 1, 1986. The results showed that this system can work not only as a load-leveling apparatus but also as a high-quality power source which can support the utility power system with its load frequency control and voltage regulation capabilities. As the second step of these R&D activities, a 1MW/8MWh sodium-sulfur battery pilot plant was constructed at the same Tatsumi site. On July 11, 1991, 1000 kW× 8H facility, the largest of its type in the world, was completed and started operation. This paper describes the construction experience and operation results of the pilot plant.
Technical Paper

12-Volt Vacuum Fluorescent Display Drive Circuitry for Electronically Tuned Radios

1986-03-01
860126
The trend towards battery voltage vacuum fluorescent displays continues the technological advances in design and construction of VFD's, as they are applied to the automobile environment. With the ever increasing use of electronic displays for electronically tuned radios (ETR's), compact disc (CD) players, and other entertainment systems, advances in battery voltage displays and their associated drive circuitry have become a necessity. With the inherent advantages of low voltage operation and high information density, VFD's will continue to dominate the automobile audio markets. This paper will discuss battery voltage displays, the basic circuitry necessary to operate a vacuum fluorescent display, and comment on the “off the shelf” controller and driver circuitry available.
Technical Paper

120VAC Power Inverters

1983-02-01
830131
Inverters are solid state devices which change DC to 120VAC electricity. They are sufficiently rugged and reliable to make them practical for use on utility vehicles for operating thumpers, tools, lights and induction motor loads. The SCR type rather than the transistor type inverter is generally required for inductive and reactive loads. Static inverters operate from battery input. They provide power without running an engine, but are limited by battery capacity so work best in intermittent load applications. Dynamic inverters operate from alternator input and will handle continuous loads to 7200 watts with truck engine running.
Technical Paper

12V/14V to 36V/42V Automotive System Supply Voltage Change and the New Technologies

2002-11-19
2002-01-3557
This paper shows some aspects of the automotive voltage energy system level shift from 14 to 42 Volts. New features and prospective emissions/fuel economy requirements are creating electrical power needs in future automobiles, which today's conventional system cannot adequately supply at 14 Vdc (nominal, with a 12 Volt battery). It will be necessary to provide electric motors, DC/DC converters, inverters, battery management, and other electronic controls to meet higher voltage requirements. Suppliers must now include 42 Volt components and systems within their product range and make these new components as light, small, and cost efficient as possible. This paper is a compilation of several published works aiming to offer a synthesis to introduce this subject to the Brazilian Automotive Market.
Journal Article

2-Stroke High Speed Diesel Engines for Light Aircraft

2011-09-11
2011-24-0089
The paper describes a numerical study, supported by experiments, on light aircraft 2-Stroke Direct Injected Diesel engines, typically rated up to 110 kW (corresponding to about 150 imperial HP). The engines must be as light as possible and they are to be directly coupled to the propeller, without reduction drive. The ensuing main design constraints are: i) in-cylinder peak pressure as low as possible (typically, no more than 120 bar); ii) maximum rotational speed limited to 2600 rpm. As far as exhaust emissions are concerned, piston aircraft engines remain unregulated but lack of visible smoke is a customer requirement, so that a value of 1 is assumed as maximum Smoke number. For the reasons clarified in the paper, only three cylinder in line engines are investigated. Reference is made to two types of scavenging and combustion systems, designed by the authors with the assistance of state-of-the-art CFD tools and described in detail in a parallel paper.
Technical Paper

2000 University of Maryland FutureTruck Design Description

2001-03-05
2001-01-0681
The University of Maryland team converted a model year 2000 Chevrolet Suburban to an ethanol-fueled hybrid-electric vehicle (HEV) and tied for first place overall in the 2000 FutureTruck competition. Competition goals include a two-thirds reduction of greenhouse gas (GHG) emissions, a reduction of exhaust emissions to meet California ultra-low emissions vehicle (ULEV) Tier II standards, and an increase in fuel economy. These goals must be met without compromising the performance, amenities, safety, or ease of manufacture of the stock Suburban. The University of Maryland FutureTruck, Proteus, addresses the competition goals with a powertrain consisting of a General Motors 3.8-L V6 engine, a 75-kW (100 hp) SatCon electric motor, and a 336-V battery pack. Additionally, Proteus incorporates several emissions-reducing and energy-saving modifications; an advanced control strategy that is implemented through use of an on-board computer and an innovative hybrid-electric drive train.
Technical Paper

240 VDC Electric Vehicle System

1979-02-01
790159
THE BATTERY is the primary component limiting electric vehicle performance that equals today's standard of expectations as defined by the I. C. engine powered vehicles. Efforts to optimize the electric vehicle performance is leading many people to select and assemble the highest efficiency components available. High voltage electric vehicle power system can provide performance advantages over lower voltage systems, but only if this voltage is in balance with the total system. Mixing high efficiency components does not Insure total system efficiency optimization. The ability of a battery to release its stored energy is a function of its demand. Higher current demands will reduce the efficiency of a battery. This paper reveals how such a mismatch occurred and its reflection on what appeared to be a battery problem.
Journal Article

26,500km Down the Pan-American Highway in an Electric Vehicle A Battery's Perspective

2012-04-16
2012-01-0123
This paper presents a novel battery degradation model based on empirical data from the Racing Green Endurance project. Using the rainflow-counting algorithm, battery charge and discharge data from an electric vehicle has been studied in order to establish more reliable and more accurate predictions for capacity and power fade of automotive traction batteries than those currently available. It is shown that for the particular lithium-iron phosphate (LiFePO₄) batteries, capacity fade is 5.8% after 87 cycles. After 3,000 cycles it is estimated to be 32%. Both capacity and power fade strongly depend on cumulative energy throughput, maximum C-rate as well as temperature.
Book

42 Volt Systems

2000-09-29
This report addresses the technical challenges engineers must face, including the issues of storage devices, generation of the 42 volts, and distribution of power. It contains information on all of the critical aspects related to the adoption of this technology.
Book

48-Volt Developments

2015-11-09
Development of higher-voltage electrical systems in vehicles has been slowly progressing over the past few decades. However, tightening vehicle efficiency and emissions regulations and increasing demand for onboard electrical power means that higher voltages, in the form of supplemental 48 V subsystems, may soon be nearing production as the most cost-effective way to meet regulations. The displacement of high-wattage loads to more efficient 48 V networks is expected to be the next step in the development of a new generation of mild hybrid vehicles. In addition to improved fuel economy and reduced emissions, 48 V systems could potentially save costs on new electrical features and help better address the emerging needs of future drivers. Challenges to 48 V system implementation remain, leading to discussions by experts from leading car makers and suppliers on the need for an international 48 V standard. Initial steps toward a proposed standard have already been taken.
Technical Paper

60 g/km CO2 Without Performance Loss

2001-11-12
2001-01-3737
The University of Liege and Breuer Technical Development, Belgium, have designed a parallel hybrid drive train, now implemented in a VW Lupo. The original objectives of the concept were the reduction of total CO2 emissions without performance loss and an acceptable zero-emission range for inner cities. This paper presents: Metropol, a homemade hybrid simulation software, including engine cold start and dynamic battery models, hybrid management strategy for the lowest CO2 emissions, final performance, consumption and emissions of the vehicle.
Technical Paper

75 AH and 10 Boilerplate Nickel-Hydrogen Battery Designs and Test Results

1992-08-03
929323
The 75 Ah actively cooled bipolar battery continues to undergo LEO life testing at 40% DOD and to date has completed 13,000 cycles. The EOC and EOD voltages indicate that there is slight degradation in the overall battery performance. The primary influence in this decline is considered to be one cell's poor performance. The potential for extended cycle life capability of bipolar batteries has been demonstrated. Ten 4-cell passively cooled bipolar batteries are on test at Space Systems/Loral (SS/L). Characterization testing has been completed. The results indicate that high capacity utilizations can be maintained at various discharge rates. Performance differences were noted and seem to be related to battery design variations. Further testing is planned.
Technical Paper

A "Hardware-Emulated" Test Analysis of a PEM-Fuel-Cell Hybrid Powertrain

2005-09-11
2005-24-040
Two testing campaigns were performed in Turin by CRF (the Fiat Research Center), and in Rome by ENEA (the Italian National Agency for New Technologies, Energy and the Environment) and the University "ROMA TRE". The work demonstrates the feature of a FC emulator to characterize fuel-cell-propelled drivetrains without employing an expensive PEM fuel cell and it points out how the vehicle fuel consumption, on a specific mission, depends on two fundamental parameters, the accordance of the FC nominal power with the requested power of the mission and the battery State-of-Charge. In the ENEA Research Center "Casaccia", near Rome, the behaviors of PEM Fuel Cells of different sizes (7, 15, 22 kW) were simulated by replacing them with a controlled AC/DC converter, this fuel cell emulator powering a full-scale hybrid drive train.
Journal Article

A Bibliographical Review of Electrical Vehicles (xEVs) Standards

2018-04-18
Abstract This work puts presents an all-inclusive state of the art bibliographical review of all categories of electrified transportation (xEVs) standards, issued by the most important standardization organizations. Firstly, the current status for the standards by major organizations is presented followed by the graphical representation of the number of standards issued. The review then takes into consideration the interpretation of the xEVs standards developed by all the major standardization organizations across the globe. The standards are differentiated categorically to deliver a coherent view of the current status followed by the explanation of the core of these standards. The ISO, IEC, SAE, IEEE, UL, ESO, NTCAS, JARI, JIS and ARAI electrified transportation vehicles xEV Standards from USA, Europe, Japan, China and India were evaluated. A total approximated of 283 standards in the area have been issued.
Technical Paper

A Capacitive Oil Deterioration Sensor

1991-02-01
910497
There is a need for sensors that respond to chemical and physical properties of engine oil. In response to this need, an experimental design of an engine-mounted, capacitive sensor has been developed to monitor changes in the dielectric constant of the engine oil. The sensing element is a small, air-gap capacitor that is mounted in a spacer ring that fits between the oil filter and the engine block. Embedded in the same spacer ring is the associated circuitry. Experiments have been carried out with experimental capacitive oil sensors mounted on engines using a typical fully-formulated, factory-fill oil. The oil dielectric constant initially decreases and is less than the starting value while the anti-oxidant additives are active. After about 1600 km, the antioxidant additives become sufficiently depleted to allow oxidation products to accumulate and for the oil dielectric constant to increase at a steady rate of about 1% per 1000 km.
Technical Paper

A Charge Sustaining Parallel HEV Application of the Transmotor

1999-03-01
1999-01-0919
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.
Technical Paper

A Close Up View of a Comparative Test on Electric Vehicle Batteries in ENEA

1997-08-06
972635
ENEA (Italian National Agency for New Technology, Energy and the Environment) has been involved in research and development in the transport sector since the '80s, to reduce energy consumption and environmental impact. Specific testing facilities have been set up in ENEA Casaccia Research Center to perform such activities: a battery test laboratory with test-bench and climatic chambers, a test track for EVs, a fleet of electric passenger cars and vans, a roller bench for medium-size vehicles and a test bed for the complete drivetrains of electric and hybrid vehicles. A test aimed at comparing bench and on-board performance of lead-acid batteries was carried out on a VRLA system, equipping a Panda Larel, using test benches for battery cycling in thermal chambers, a track and the roller stand. For the track testing of a vehicle a special cycle was elaborated, that is similar in some specific properties to the ECE 15, an European cycle proposed for evaluating energy consumption.
Technical Paper

A Commercially-Viable Electric Car

1991-09-01
911919
The present traffic and pollution situation in our large cities and the inefficient use of the internal combustion engine car in city traffic, has been for a long time the catalyst to develop specific city cars, which can reduce the burden on the environment and be more economical to operate. Several electric cars have been introduced in the past without success. The power/weight ratio of the present lead-acid batteries has been a limiting factor for the commercial success of an electric vehicle. In addition to this the high initial cost, limited range, and high operating cost have contributed to the low level of interest by the general public. This paper describes the development of a commercially viable electric car based on a range-extending battery system. This car is also designed to be utilised with quick-change battery modules.
Technical Paper

A Comparative Review of Fuel Cell Vehicles (FCVs) and Hybrid Electric Vehicles (HEVs) Part I: Performance and Parameter Characteristics, Emissions, Well-to-Wheels Efficiency and Fuel Economy, Alternative Fuels, Hybridization of FCV, and Batteries for Hybrid Vehicles

2003-06-23
2003-01-2298
Currently, almost all the activities in the development of new generation of vehicles are focused on fuel cell powered vehicles (FCVs) and hybrid electric vehicles (HEVs). However, there are still uncertainties as to which provides the maximum benefits in terms of performance, energy savings and impact on the environment. This paper compares the performance and parameter characteristics of FCVs and HEVs with a view towards an objective assessment of the relative performance of these vehicles. In particular, this paper reviews major characteristics of FCVs as zero or ultra-low emission vehicles (ZEV/ULEVs), their presumed high efficiency and potential for using alternative fuels, while also considering their limited performance at high power demands.
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