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As part of the U.S. Environmental Protection Agency’s (EPA’s) continuing assessment of advanced light-duty automotive technologies in support of regulatory and compliance programs, a development project was started to study various test methods to benchmark Electric Drive Units (EDUs) consisting of an electric motor, inverter and a speed-reduction gearset. Several test methods were identified for consideration, including both in-vehicle testing of the complete EDU and stand-alone testing of the EDU and its subcomponents after removal from the vehicle. In all test methods explored, sweeps of speed and torque test points were conducted while collecting key EDU data required to determine efficiency, including motor torque and speed, direct current (DC) battery voltage and current into the inverter, and three-phase alternating current (AC) phase voltages and currents out of the inverter and into the electric motor.

Emissions from manual transmission motorcycles have been shown to be dependent upon transmission shift patterns. Presently, when undergoing an emission test for an Environmental Protection Agency (EPA) certification a manufacturer can designate their own shift points during the cycle or utilize an EPA prescribed shift pattern which uses basic up or down shifts at specific speeds regardless of the type of motorcycle, 40 CFR 86.528-78(h). In order to predict the real-life emissions from motorcycles, a comparative real-life shift pattern has been developed which can then be used to evaluate the suitability of the manufacturer’s shift schedule. To that end, a model that predicts shift points for motorcycles has been created. This model is based on the actual operation of different motorcycles by real life operators in a combined city and highway setting.

As part of the midterm evaluation of the 2022-2025 Light-Duty Vehicle Greenhouse Gas (GHG) Standards, the U.S. Environmental Protection Agency (EPA) developed simulation models for studying the effectiveness of 48V mild hybrid electric vehicle (MHEV) technology for reducing CO2 emissions from light-duty vehicles. Simulation and modeling of this technology requires a suitable model of the battery. This article presents the development and validation of a 48V lithium-ion battery model that will be integrated into EPA’s Advanced Light-Duty Powertrain and Hybrid Analysis (ALPHA) vehicle simulation model and that can also be used within Gamma Technologies, LLC (Westmont, IL) GT-DRIVE™ vehicle simulations. The battery model is a standard equivalent circuit model with the two-time constant resistance-capacitance (RC) blocks.

As part of the U.S. Environmental Protection Agency’s (EPA’s) continuing assessment of advanced light-duty (LD) automotive technologies to support the setting of appropriate national greenhouse gas (GHG) standards and to evaluate the impact of new technologies on in-use emissions, a 2016 Honda Civic with a 4-cylinder 1.5-liter L15B7 turbocharged engine and continuously variable transmission (CVT) was benchmarked. The test method involved installing the engine and its CVT in an engine-dynamometer test cell with the engine wiring harness tethered to its vehicle parked outside the test cell. Engine and transmission torque, fuel flow, key engine temperatures and pressures, and onboard diagnostics (OBD)/Controller Area Network (CAN) bus data were recorded.

The Advanced Light-Duty Powertrain and Hybrid Analysis tool (ALPHA) was created by EPA to evaluate the Greenhouse Gas (GHG) emissions of Light-Duty (LD) vehicles. ALPHA is a physics-based, forward-looking, full vehicle computer simulator capable of analyzing various vehicle types combined with different powertrain technologies. The ALPHA desktop application was developed using MATLAB/Simulink. The ALPHA tool was used to evaluate technology effectiveness and off-cycle technologies such as air-conditioning, electrical load reduction technology and road load reduction technologies of conventional, non-hybrid vehicles for the Midterm Evaluation of the 2017-2025 LD GHG rule by the U.S. Environmental Protection Agency (EPA) Office of Transportation and Air Quality (OTAQ).

The U.S. Environmental Protection Agency (EPA) contracted with FEV, Inc. to estimate the per-vehicle cost of employing selected advanced efficiency-improving technologies in light-duty motor vehicles. The development of transparent, reliable cost analyses that are accessible to all interested stakeholders has played a crucial role in establishing feasible and cost effective standards to improve fuel economy and reduce greenhouse gas (GHG) emissions. The FEV team, together with engineering staff from EPA's National Vehicle and Fuel Emissions Laboratory, and FEV's subcontractor, Munro & Associates, developed a robust costing methodology based on tearing down, to the piece part level, relevant systems, sub-systems, and assemblies from vehicles “with and without” the technologies being evaluated.

Plug-in hybrid electric vehicles (PHEVs) have the ability to significantly reduce petroleum consumption. Argonne National Laboratory (Argonne), working with the FreedomCAR and Fuels Partnership, helped define the battery requirements for PHEVs. Previous studies demonstrated the impact of the vehicle's characteristics, such as its class, mass, or electrical accessories, on the requirements. However, questions on the impact of drive cycles remain outstanding. In this paper, we evaluate the consequences of sizing the electrical machine and the battery to follow standard drive cycles, such as the urban dynamometer driving schedule (UDDS), as well as real-world drive cycles in electric vehicle (EV) mode. The requirements are defined for several driving conditions (e.g., urban, highway) and types of driving behavior (e.g., smooth, aggressive).

The attractiveness of the hydraulic hybrid concept stems from the high power density and efficiency of the pump/motors and the accumulator. This is particularly advantageous in applications to heavy vehicles, as high mass translates into high rates of energy flows through the system. Using dry case hydraulic pumps further improves the energy conversion in the system, as they have 1-4% better efficiency than traditional wet-case pumps. However, evacuation of fluid from the case introduces air bubbles and it becomes imperative to address the deaeration problems. This research develops a bubble elimination efficiency testing apparatus (BEETA) to establish quantitative results characterizing bubble removal from hydraulic fluid in a cyclone deaeration device. The BEETA system mixes the oil and air according to predetermined ratio, passes the mixture through a cyclone deaeration device, and then measures the concentration of air in the exiting fluid.

The United States Environmental Protection Agency (EPA) has initiated Phase I of a regulatory program to control exhaust emissions of nonroad diesel engines over 37 kW. Central to any emissions regulation is the test procedure, which must include an appropriate test cycle. Based on actual in-use speed and estimated torque data collected from an agricultural tractor, a backhoe-loader, and a crawler tractor, three duty cycles were developed. Using an iterative process, comparison of chi-square statistical data was used to identify representative microtrips, segments of engine operation gathered during performance of selected activities. Representative microtrips for specific activities for a particular nonroad application were “strung” together to make up a test cycle. Before accepting the test cycle, data for the cycle was compared to statistical data used to characterize the raw data in an effort to validate that the cycle was representative of the raw data.

A second carbonyl round robin was conducted to enable participating laboratories doing routine analysis of carbonyls in vehicle exhaust emissions to assess their analytical capabilities. Three sets of solutions in acetonitrile containing varying number and amounts of standard DNPH-carbonyls were prepared. The parent carbonyls are known components of vehicle exhaust emissions. The samples were designed to challenge the capabilities of the participants to separate, identify and quantify all the components. The fourteen participating laboratories included automotive, contract, petroleum and regulatory organizations. All participants were able to separate and identify the C3 carbonyls; a few were not able to separate MEK from butyraldehyde and methacrolein from butyraldehyde; and many were not able to separate adequately the isomers of tolualdehyde. Inadequate separation and lack of appropriate standards resulted in a few misidentifications.

Twenty in-use vehicles that had failed the I/M test in the State of Michigan were inspected for engine mechanical condition as well as the state of the emission control system. Mass emission tests were conducted before and after repairs to the emission control system. The internal engine condition (i.e., high or low levels of cylinder leakage, or compression difference) showed little effect on the ability of the repaired vehicles to achieve moderate mass emission levels. Nine of the twenty vehicles were recruited after three years, and with the exception of tampering, the original emission control system repairs proved to be durable.

Simple tests were performed to investigate the operating characteristics of zirconia galvanic cells (lambda sensors) in automotive closed loop “three-way” emission control systems. Commercially available cells were exposed to typical gaseous components of exhaust gas mixtures. The voltages generated by the cells were at their maximum values when hydrogen, and, in some instances, carbon monoxide, was available for reaction with atmospheric oxygen that migrated through the cells' ceramic thimbles in ionic form. This dependence of galvanic activity on the availability of these particular reducing agents indicated that the cells were voltaic devices which operated as oxidation/reduction reaction cells, rather than simple oxygen concentration cells.

There has been considerable interest in applying remote measuring methods to sample in-use vehicle emissions, and to characterize fleet emission behavior. A Remote Sensing Device (RSD) was used to measure on-road carbon monoxide (CO) emissions from approximately 350 in-use vehicles that had undergone transient mass emission testing at a centralized I/M lane. On-road hydrocarbon (HC) emissions were also measured by the RSD on about 50 of these vehicles. Analysis of the data indicates that the RSD identified a comparable number of the high CO emitters as the two speed I/M test only when an RSD cutpoint much more stringent than current practice was used. Both RSD and I/M had significant errors of omission in identifying High CO Emitters based on the mass emission test. The test data were also used to study the ability of the RSD to characterize fleet CO emissions.

The application of resistive materials as part of an exhaust emission control system is presented and discussed. The importance of cold start emissions is emphasized, and results are presented from experiments conducted with two different conductive materials. Most of the testing was conducted using methanol as the fuel, although some tests were run using gasoline-fueled vehicles.

This, the fourteenth in this series of papers, examines trends in fuel economy, technology usage and estimated 0 to 60 MPH acceleration time for model year 1986 passenger cars. Comparisons with previous year's data are made for the fleet as a whole and using three measures of vehicle/engine size: number of cylinders, EPA car class, and inertia weight class. Emphasis on vehicle performance and fuel metering has been expanded and analysis of individual manufacturers has been deemphasized; comparisons of the Domestic, European, and Japanese market sectors are given increased emphasis.

This, the thirteenth in a series of papers on trends in EPA fuel economy, covers both passenger cars and light trucks and concentrates on the current model year, 1985. It differs from previous papers in two ways: 1) Model years 1975, 1980 and 1985 are highlighted, with the model years in between these rarely discussed; 2) The progress of the industry, as a whole, in improving fuel economy since 1975 is emphasized, and individual manufacturer data are de-emphasized. Conclusions are presented on the trends in fuel economy of the car and light truck fleets; the Domestic, European and Japanese market sectors; and various vehicle classes.

The increased interest in use of methanol makes it important to determine what levels of methanol and formaldehyde emissions may be acceptable. This paper reviews the available health data for methanol and formaldehyde to define what approximate ranges of concentrations, termed ranges of concern, could be acceptable from a toxicological viewpoint. Air quality models are then used to predict the in-use fleet average exhaust emission levels in localized situations (heavily impacted by mobile sources) corresponding to these ranges of concern. Using predicted fleet compositions, approximate target emission levels are given for the light-duty portion of the fleet which could yield these fleet averages. Finally, there is a brief summary of available methanol and formaldehyde emissions data from neat methanol-fueled vehicles which are compared to the target levels.

This the twelfth in a series of Papers on trends in EPA fuel economy, concentrates as usual on the current Model Year (1984). Final Corporate Average Fuel Economy (CAFE) production volumes and MPG figures have been used to update the data bases through the 1982 Model Year. This paper is different from earlier papers in four ways: 1) manufacturer-supplied production forecasts have been adjusted for both model years 1983 and 1984. 2) sales weighted MPG values at the nameplate level of aggregation are presented. 3) much of the analysis is stratified at the Domestic/European/Japanese manufacturer level, and 4) fuel economy analysis for Light Duty Trucks is not included. Conclusions are presented on the trends in fuel economy of the fleet as a whole and for various classes of vehicles.

This paper presents the results of several emission testing programs conducted by the U.S. Environmental Protection Agency. The test vehicles were primarily 1980 and 1981 passenger cars which were obtained at random from private owners. Some 1982 models were also tested. The 1328 vehicles were selected from the Los Angeles area as well as from a number of other low-altitude locations. The test sequence included the Federal Test Procedure, the Highway Fuel Economy Test and several short cycle tests. The primary purpose of the program was to gather information on current vehicles which could be used in calculations and projections of air quality and aid development of programs to improve it. The results of the program indicate that these vehicles are capable of maintaining low emission levels although high levels are also possible due to defects, deterioration, or tampering. Inspection/Maintenance programs are a feasible and effective means for correcting high levels when they occur.

EPA Fuel economy figures are presented for model year 1982 cars and light duty trucks. Comparisons with the MPG figures of prior years are included. Sales penetrations of various vehicle, engine, and emission control design features are given, and domestic cars' MPG characteristics are compared to that of imports', gasoline vehicle MPG is compared to Diesel MPG, and 49-states MPG is compared to California MPG. Usage of newer vehicle technologies is continuing to increase, leading to continued growth in fuel economy capability in spite of stringent emission standards.