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Viewing 211 to 240 of 109901
2017-03-28
Technical Paper
2017-01-1288
Noriko Shisa, Shinsuke Ishihara, Yougui Huang, Mikio Asai, Katsuhiko Ariga
Abstract Despite the fact that methanol is toxic to human health and causes serious damage to automobile engines and fuel system components, methanol-containing gasoline is becoming popular in some areas. Methanol demonstrates similar chemical properties to ethanol (which is already established as an additive to gasoline), so that it is difficult to identify methanol-containing gasoline without performing proper chemical analysis. In this study, we report a low-cost, portable, and easy-to-operate sensor that selectively changes color in response to methanol contained in gasoline. The colorimetric sensor will be useful for automobile users to avoid methanol-containing gasoline upon refueling.
2017-03-28
Technical Paper
2017-01-1291
Ashraya Gupta, Harshil Kathpalia, Harshit Aggarwal, Naveen Kumar
Abstract The increment in the application of fossil fuels is leading the world into a catastrophic state both environmentally and economically. Current demand for fuels exceeds its imminent supply and rather sooner than later energy demands will have to shift towards non-conventional fuels to cope with the situation. With constant developments in the automotive sector, several solutions have been found but none have been as good as gasoline to substitute it in the commercial market. One such solution being compressed air might solve this global fuel crisis, which serves a glowing advantage of being cheaper and greener as it produces zero tail-pipe emissions, and can help in decreasing automobile’s contribution to global warming. Though the potential energy stored in the compressed air limits its application to light duty vehicles and still there will be a need for other alternative solutions for the heavy duty vehicles in order to relieve the pressure from the fossil fuels.
2017-03-28
Technical Paper
2017-01-1292
Saiful Bari, Idris Saad
Abstract Diesel engine can be run with biodiesel which has the potential to supplement the receding supply of crude oil. As biodiesel possess similar physiochemical properties to diesel, most diesel engines can run with biodiesel with minimum modifications. However, the viscosity of biodiesel is higher, and the calorific value is lower than diesel. Therefore, when biodiesel is used in diesel engines, it is usually blended with diesel at different proportions. Use of 100% biodiesel in diesel engines shows inferior performance of having lower power and torque. Improving in-cylinder airflow characteristic to break down higher viscous biodiesel and to improve air-fuel mixing are the aims of this research. Therefore, guide vanes in the intake runner were used in this research to improve the performance of diesel engine run with biodiesel.
2017-03-28
Technical Paper
2017-01-1300
Raj Jayachandran, Bhimaraddi Alavandi, Matt Niesluchowski, Erika Low, Yafang Miao, Yi Zhang
Abstract An engine cooling system in an automotive vehicle comprises of heat exchangers such as a radiator, charge air cooler and oil coolers along with engine cooling fan. Typical automotive engine-cooling fan assembly includes an electric motor mounted on a shroud that encloses the radiator core. One of main drivers of fan shroud design is Noise, Vibration, and Harshness (NVH) requirements without compromising the main function of airflow for cooling requirements. In addition, there is also a minimum stiffness requirement of fan shroud which is often overlooked in arriving at optimal design of it. Low Speed Damageability (LSD) assessment of an automotive vehicle is about minimizing the cost of repair of vehicle damages in low speed crashes. In low speed accidents, these fan motors are subjected to sudden decelerations which cause fan motors to swing forward thereby damaging the radiator core. So designing fan shroud for low speed damageability is of importance today.
2017-03-28
Technical Paper
2017-01-1299
Nagurbabu Noorbhasha, Brendan J. O'Toole
Abstract The objective of this research is to design and analyze a roll cage structure for an off-road vehicle that was used for SAE Baja competition by UNLV SAE Baja team. Baja SAE is an intercollegiate competition to design, fabricate, and race a small, single passenger, off-road vehicle powered by a 10 HP Briggs Stratton 4-Stroke gasoline engine. Since the off-road vehicle is powered by a small capacity engine, the weight of the structure is very critical and must be optimized to improve the performance of the vehicle. In an effort to optimize the structure, a finite element analysis (FEA) was performed and the effects of stress and deformation were studied for a linear static frontal impact analysis on roll cage structure. The frame was further modified for structural rigidity. Additional strengthening gussets were added at the locations of high stresses to reduce the stress concentration.
2017-03-28
Technical Paper
2017-01-1059
Rong Guo, Jun Gao, Xiao-kang Wei
Abstract The active engine mount (AEM) is developed in automotive industry to improve overall NVH performance. The AEM is designed to reduce major-order signals of engine vibration over a broad frequency range, therefore it is of vital importance to extract major-order signals from vibration before the actuator of the AEM works. This work focuses on a method of real-time extraction of the major-order acceleration signals at the passive side of the AEM. Firstly, the transient engine speed is tracked and calculated, from which the FFT method with a constant sampling rate is used to identify the time-related frequencies as the fundamental frequencies. Then the major-order signals in frequency domain are computed according to the certain multiple relation of the fundamental frequencies. After that, the major-order signals can be reconstructed in time domain, which are proved accurate through offline simulation, compared with the given signals.
2017-03-28
Technical Paper
2017-01-1058
L.V. Pavan Kumar Maddula, Ibrahim Awara
Abstract Increased focus on fuel efficiency and vehicle emissions has led the automotive industry to look into low weight alternative designs for powertrain system components. These new design changes pose challenges to vehicle attributes like NVH, durability, etc. Further, the requirement of high power applications produces even more complexities. The present work explains how a potential design change of half shafts driven by a desire to reduce weight and cost can lead to NVH problems caused by half shaft resonances and explains how using multiple dynamic vibration absorbers can solve the issue to meet customer expectation while improving efficiency. With the aid of Finite Element Analysis (FEA) & optimization software, interactions between multiple DVA’s on a system was understood and optimal damper parameters for effective damping was identified. The final DVA design was tested and verified on the vehicle for optimal attribute performance.
2017-03-28
Technical Paper
2017-01-1192
Amardeep Sidhu, Afshin Izadian, Sohel Anwar
In this paper, multiple-model adaptive estimation techniques have been successfully applied to fault detection and identification in lithium-ion batteries. The diagnostic performance of a battery depends greatly on the modeling technique used in representing the system and the associated faults under investigation. Here, both linear and non-linear battery modeling techniques are evaluated and the effects of battery model and noise estimation on the over-charge and over-discharge fault diagnosis performance are studied. Based on the experimental data obtained under the same fault scenarios for a single cell, the non-linear model based detection method is found to perform much better in accurately detecting the faults in real time when compared to those using linear model based method.
2017-03-28
Technical Paper
2017-01-1194
Qiaohua Fang, Xuezhe Wei, Haifeng Dai
Abstract Parallel-connected modules have been widely used in battery packs for electric vehicles nowadays. Unlike series-connected modules, the direct state inconsistency caused by parameter inconsistency in parallel modules is current and temperature non-uniformity, thus resulting in the inconsistency in the speed of aging among cells. Consequently, the evolution pattern of parameter inconsistency is different from that of series-connected modules. Since it’s practically impossible to monitor each cell’s current and temperature information in battery packs, considering cost and energy efficiency, it’s necessary to study how the parameter inconsistency evolves in parallel modules considering the initial parameter distribution, topology design and working condition. In this study, we assigned cells of 18650 format into several groups regarding the degree of capacity and resistance inconsistency. Then all groups are cycled under different environmental temperature and current profile.
2017-03-28
Technical Paper
2017-01-1195
Masahiro Kimoto
Abstract SAE standards require the function of a Manual Service Disconnect (MSD), when open, to remove any voltage between positive and negative Rechargeable Energy Storage System (RESS) output terminals. Another SAE standard specifies that measured voltage across all external battery terminal sets shall be less than 60 VDC within 5 seconds after the manual disconnect is actuated with the automatic disconnect (e.g., contactors) closed. In this paper, the location of the manual service disconnect is reviewed to meet isolation requirement of the battery pack system (i.e., RESS). Battery architectures with manual service disconnect located at the most positive side, most negative side, and center of the array or the pack were studied. Voltage measurement points and single point failure modes were considered. It was found that MSD location for a single contactor pack is most effective in reducing voltage potential at the terminals when placed on the other side of the contactor.
2017-03-28
Technical Paper
2017-01-1190
Patrick Maguire, Hyung Baek, Stephen Liptak, Olivia Lomax, Rodolfo Palma, Yi Zhang
Abstract As electrified powertrains proliferate through original equipment manufacturer vehicle offerings, the focus on system cost and weight reduction intensifies. This paper describes the development and evaluation of a High Voltage (HV) battery system enclosure molded from High Density Polyethylene (HDPE) to deliver substantial cost and weight opportunities. While previous HV battery system enclosure alternatives to steel and aluminum focus on thermoset composites and glass filled polypropylene, this solution leverages select HDPE design techniques established for fuel tanks and applies them to an HV battery system. The result is a tough, energy absorbing structure, capable of hermetic sealing, which simplifies manufacturing by eliminating nearly all fasteners.
2017-03-28
Technical Paper
2017-01-1191
Patrick Wesskamp, Simon Reitemeyer, Joachim Melbert
Abstract This work provides a new method for estimating the capacity of an automotive Lithium-Ion cell under real application conditions present in Hybrid and Electrical vehicles. Reliable online capacity estimation is needed for accurate prediction of the remaining electrical driving range. This is a crucial criterion for customer acceptance of Electrical vehicles. Dynamic excitations of real driving cycles, temperature variation as well as the variation of electrical battery behavior with capacity and resistance degradation are challenges that need to be overcome. For this paper, a long-term aging study on 120 automotive Lithium-Ion cells is evaluated with respect to the correlation between electrical cell behavior, temperature and the cell capacity over the complete cell lifetime. The results are used for a dynamic state-space model which provides the current-voltage relationship valid for all aging states of the battery.
2017-03-28
Technical Paper
2017-01-1214
Jujun Xia, Haifeng Dai, Zechang Sun, Massimo Venturi
Abstract Lithium-ion batteries have been applied in the new energy vehicles more and more widely. The inconsistency of battery cells imposes a lot of difficulties in parameter and state estimations. This paper proposes a new algorithm which can online identify the parameters of each individual battery cell accurately with limited increase of computational cost. An equivalent circuit battery model is founded and based on the RLS (recursive least squares) algorithm, an optimization algorithm with the construction of weight vectors is proposed which can identify the parameters of lithium battery pack considering inconsistency of single battery cell. Firstly, the average value of the parameters of the battery pack is identified with the traditional RLS algorithm. Then the ratios between the parameters of each battery cell can be deduced from the mathematical model of battery. These ratios are used to determine the weight vector of each parameter of individual battery cells.
2017-03-28
Technical Paper
2017-01-1210
R. Dyche Anderson, Regan Zane, Gregory Plett, Dragan Maksimovic, Kandler Smith, M. Scott Trimboli
Abstract A new cell balancing technology was developed under a Department of Energy contract which merges the DC/DC converter function into cell balancing. Instead of conventional passive cell balancing technology which bypasses current through a resistor, or active cell balancing which moves current from one cell to another, with significant cost and additional inefficiencies, this concept takes variable amount of current from each cell or small group of cells and converts it to current for the low voltage system.
2017-03-28
Technical Paper
2017-01-1206
Zhihong Jin, Zhenli Zhang, Perry Wyatt
Abstract Power limit estimation of a lithium-ion battery system plays an important balancing role of optimizing the battery design cost, maximizing for power and energy, and protecting the battery from abusive usage to achieve the intended life. The power capability estimation of any given lithium-ion battery system is impacted by the variability of many sources, such as cell and system components resistance, temperature, cell capacity, and real time state of charge and state of health estimation errors. This causes a distribution of power capability among battery packs that are built to the same design specification. We demonstrated that real time power limit estimation can only partially address the system variability due to the errors introduced by itself. Integrating feedback control algorithms with the lithium-ion battery model maximizes the battery power capability, improves the battery robustness to variabilities, and reduces the real time estimation errors.
2017-03-28
Technical Paper
2017-01-1208
Kristin R. Cooney
Abstract This paper will discuss a compliance demonstration methodology for UN38.3, an international regulation which includes a series of tests that, when successfully met, ensure that lithium metal and lithium ion batteries can be safely transported. Many battery safety regulations, such as FMVSS and ECE, include post-crash criteria that are clearly defined. UN38.3 is unique in that the severity of the tests drove changes to battery design and function. Another unique aspect of UN38.3 is that the regulatory language can lead to different interpretations on how to run the tests and apply pass/fail criteria; there is enough ambiguity that the tests could be run very differently yet all meet the actual wording of the regulation. A process was created detailing exactly how to run the tests to improve consistency among test engineers. As part of this exercise, several tools were created which assist in generating a test plan that complies with the UN38.3 regulation.
2017-03-28
Technical Paper
2017-01-1205
Letao Zhu, Zechang Sun, Xuezhe Wei, Haifeng Dai
Abstract To monitor and guarantee batteries of electric vehicles in normal operation, battery models should be established primarily for the further application in battery management system such as parameter identification and state estimation including state of charge (SOC), state of health (SOH) and so on. In this paper, an improved battery modeling method is proposed which is based on the recursive least square (RLS) algorithm employing an optimized objective function. The proposed modified objective function not only includes the normal sum of voltage error squares between measured voltage and model output voltage but also introduces a new variable representing the sum of first order difference error squares for both kinds of voltages. This specialty can undoubtedly guarantee better agreement for the measured output and the model output. The battery model used in this paper is selected to be the conventional second order equivalent circuit model.
2017-03-28
Technical Paper
2017-01-1207
Satyam Panchal, Scott Mathewson, Roydon Fraser, Richard Culham, Michael Fowler
Abstract Lithium-ion batteries, which are nowadays common in laptops, cell phones, toys, and other portable electronic devices, are also viewed as a most promising advanced technology for electric and hybrid electric vehicles (EVs and HEVs), but battery manufacturers and automakers must understand the performance of these batteries when they are scaled up to the large sizes needed for the propulsion of the vehicle. In addition, accurate thermo-physical property input is crucial to thermal modeling. Therefore, a designer must study the thermal characteristics of batteries for improvement in the design of a thermal management system and also for thermal modeling. This work presents a purely experimental thermal characterization in terms of measurement of the temperature gradient and temperature response of a lithium-ion battery utilizing a promising electrode material, LiFePO4, in a prismatic pouch configuration.
2017-03-28
Technical Paper
2017-01-1202
Ben Tabatowski-Bush
Abstract The Battery Monitoring Integrated Circuit (BMIC) is a key technology for Battery Electronics in the electrification of vehicles. Generally speaking, every production hybrid, plug-in hybrid, and battery electric vehicle uses some type of BMIC to monitor the voltage of each lithium battery cell. In order to achieve Functional Safety for the traction battery packs for these electrified vehicles, most designs require higher ASIL ratings for the BMIC such as C or D. For the entire market of available BMIC’s, there is a generic feature set that can be found on almost every IC on the market, such as a front end multiplexer, one or more precision references, one or more Analog to Digital (A/D) converters, a power supply, communications circuits, and window comparators. There is also a fairly consistent suite of self-diagnostics, available on just about every available BMIC, to detect failures and enable achievement of the appropriate ASIL rating.
2017-03-28
Technical Paper
2017-01-1203
Takashi Inamoto, Lawrence Alger
Abstract Recent electric vehicles use Li-ion batteries to power the main electric motor. To maintain the safety of the main electric motor battery using Li-ion cells, it is necessary to monitor the voltage of each cell. DENSO has developed a battery Electronic Control Unit (ECU) that contributes greatly to the reduction of the cost and the improvement of the reliability of the system. Each manufacturer has been developing a dedicated IC for monitoring the voltages of each cell of a battery. However, since the number of cells that can be monitored is limited, more than one IC is required to measure the voltages of a large number of cells. The increase in the number of ICs and the amount of insulator leads to the rise in system cost. DENSO has developed a dedicated IC that uses a proprietary high-breakdown voltage process, and which enables monitoring up to 24 cells with a single IC chip.
2017-03-28
Technical Paper
2017-01-1233
Mohamed A. Elshaer, Allan Gale, Chingchi Chen
Abstract Vehicle safety is of paramount importance when it comes to plugging the vehicle into the electric utility grid. The impact of high voltage ground fault has been neglected or, if not, addressed by guidelines extracted from general practices, written in international standards. The agile accretion in Electric Vehicle (EV) development deems an exhaustive study on safety risks pertaining to fault occurrence. While vehicle electrification offers a vital solution to oil scarcity, it is essential that the fast development of the number of electric vehicles on the road does not compromise safety. Meanwhile, the link between technology and demands of society must be governed by vehicle safety. In this paper, a comprehensive study on high voltage (HV) fault conditions occurring in an EV will be conducted. In the next decade, EVs are expected to be prevalent worldwide. Ground fault characteristics are significantly dependent on the earthing system.
2017-03-28
Technical Paper
2017-01-1230
Cyrille Goldstein, Joel Hetrick
Abstract Mechanical losses in electric machines can contribute significantly to overall system losses in an electric drive [1]. With a permanent magnet synchronous machine (PMSM), measuring mechanical losses is difficult without an un-magnetized rotor. Even with an un-magnetized rotor, physical testing can be time consuming and expensive. This paper presents a simple theoretical model of mechanical drag in an electric machine. The model was built using calculations for bearing, seal, and windage drag and was compared to experimental results from testing with un-magnetized motors. Based on this information, the model was modified to better represent the physical system. The goal of this work is to understand the contributors to mechanical drag, to be able to estimate mechanical losses without physical testing, and to be able to quickly evaluate design choices that could reduce mechanical losses.
2017-03-28
Technical Paper
2017-01-1223
Ji Zhang, Mengjing Shen, Xi Zhao
Abstract There are many electronic devices in electric vehicle (EV), making its electromagnetic compatibility (EMC) serious. Motor drive system is the main interference source of EV, whose electromagnetic interference (EMI) is much worse than conventional vehicle. In this paper, the motor drive system of EV was mainly researched, and a co-simulation method was proposed: control system and motor model were established with Matlab, and the equivalent circuit model of inverter and the cable model were established with Saber. By this way, a complete motor drive system model for conductive EMI was obtained. This modeling method can not only accurately establish the EMI sources and coupling paths, but can simulate the control strategy and operating conditions.
2017-03-28
Technical Paper
2017-01-1222
Jeongwon Rho, Jeongbin Yim, Daewoong Han, Gubae Kang, Seongyeop Lim
Abstract The current sensor for motor control is one of the main components in inverters for eco-friendly vehicles. Recently, as the higher performance of torque control has become required, the current sensor measurement error and accuracy of motor controls have become more significant. Since the response time of the sensor affects the motor output power, the response delay of the sensor causes measurement errors of the current. Accordingly, the voltage vector changes, and a motor output power deviation occurs. In the case of the large response delay of the sensor, as motor speed increases, then difference between motoring and generating output power becomes larger and larger. This results in the deterioration of power performance in high-speed operation. The deviation of the voltage vector magnitude is the main cause of motor output power deviation and imbalance through the simulation.
2017-03-28
Technical Paper
2017-01-1219
Steven G. Rinaldo, Zhihong Jin, Perry Wyatt
Abstract Validation of the State-Of-Function (SOF) algorithm and associated cell models are critical for battery management as they are responsible for optimal pack power utilization as well as safety protection and life. The SOF accomplishes this optimization task by communicating pack level operation limits related to power, current, voltage and temperature. These operation limits are, in some cases, estimated via parameters and equations derived from cell models. Correspondingly, any errors within the cell models will propagate into the model-dependent SOF limits. Understanding the source of errors and thus finding areas for improvement requires a visualization-based SOF validation strategy.
2017-03-28
Technical Paper
2017-01-1220
Ahmad Arshan Khan
Abstract In an interior permanent magnet machine, magnet temperature plays a critical role in determining optimal current control trajectory. Monitoring magnet temperature is a challenging task. In lab and various specialized applications, infrared sensors or thermocouples are used to measure the temperature. But it adds cost, maintenance issues and their integration to electric machine drives could be complicated. To tackle issues due to sensor based methods, various sensorless model based approaches are proposed in the literature recently such as flux observer, high-frequency signal injection, and thermal models, etc. Although magnet temperature monitoring received a lot of attention of researchers, very few papers give a detailed overview of the effects of magnet temperature on motor control from a controls perspective. This paper discusses the impact of magnet temperature variation on Maximum Torque per Ampere control and Flux Weakening Control trajectory.
2017-03-28
Technical Paper
2017-01-1217
Jiangong Zhu, Zechang Sun, Xuezhe Wei, Haifeng Dai
Abstract An alternating current (AC) heating method for a NMC lithium-ion battery with 8Ah capacity is proposed. The effects of excitation frequency, current amplitudes, and voltage limit condition on the temperature evolution are investigated experimentally. Current amplitudes are set to 24A(3C), 40(5C), and 64A(8C), and excitation frequencies are set to 300Hz, 100Hz, 30Hz, 10Hz, 5Hz, and 1Hz respectively. The voltage limitations are necessary to protect cells from overcharge and over-discharge. Therefore the voltage limit condition (4.2V/2.75V, 4.3V/2.65V, and 4.4V/2.55V) are also considered in depth to verify the feasibility of the AC heating method. The temperature rises prominently as the current increases, and the decrement of frequencies also lead to the obvious growth of battery temperature. The battery obtain the maximum temperature rise at 64A and 1Hz, which takes 1800s to heat up the battery from -25°C to 18°C.
2017-03-28
Technical Paper
2017-01-1252
Ming Cheng, Lei Feng, Bo Chen
Abstract This paper studies the nonlinear model predictive control for a power-split Hybrid Electric Vehicle (HEV) power management system to improve the fuel economy. In this paper, a physics-based battery model is built and integrated with a base HEV model from Autonomie®, a powertrain and vehicle model architecture and development software from Argonne National Laboratory. The original equivalent circuit battery model from the software has been replaced by a single particle electrochemical lithium ion battery model. A predictive model that predicts the driver’s power request, the battery state of charge (SOC) and the engine fuel consumption is studied and used for the nonlinear model predictive controller (NMPC). A dedicated NMPC algorithm and its solver are developed and validated with the integrated HEV model. The performance of the NMPC algorithm is compared with that of a rule-based controller.
2017-03-28
Technical Paper
2017-01-1251
Bin Zhou, Jeffrey Burl, Amir Rezaei
Abstract This paper presents results on how the Equivalent Consumption Minimization Strategy (ECMS) penalty factor effects Lithium ion battery aging. The vehicle studied is the Honda Civic Hybrid. The battery used is A123 Systems’. Vehicle simulation using multiple combinations of highway and city drive cycles. For each combination of drive cycles, six ECMS penalty factor values are used. Battery aging is evaluated using a semi-empirical model combined with accumulated Ah-throughput method which uses, as an input, the battery state of charge trajectory from the vehicle simulations. The tradeoff between fuel cost and battery aging cost is explicitly displayed. In addition, the results provide insight into how driving behavior affects battery aging. The paper concludes with a discussion of the optimal balance between fuel cost and battery aging.
2017-03-28
Technical Paper
2017-01-1247
Mohammed Khorshed Alam, Lihua Chen, Yan Zhou, Fan Xu, Shuitao Yang
Abstract Direct bypass to DC-DC boost converter in traction inverter increases converter's capability and efficiency significantly by providing a lower loss path for power flow between the battery and DC-link terminal. A bypass using diode is an excellent solution to achieve this capability at low cost and system complexity. Bypass diode operates in the linear operating region (DC Q-point) when the battery discharges through the bypass diode to drive the electric motors. Therefore, thermal stress on the DC-link capacitor is shared between the input and DC-link capacitors through the bypass diode. On the other hand, inverters introduce voltage oscillation in the DC-link terminal which results in unwanted energy oscillation through the bypass diode during battery charging. Both of these phenomena have been explained in details.
Viewing 211 to 240 of 109901