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Viewing 271 to 300 of 19895
2017-03-28
Journal Article
2017-01-1216
Edward C. Fontana, Rick Barnett, Robert Catalano, James Harvey, Jiacheng He, George Ottinger, John Steel
Abstract Electric cars can help cities solve air quality problems, but drivers who live in apartments have no convenient way to charge daily, absent the well-controlled private garages where most electric vehicles (EVs) are currently charged each night. Environmentally robust, hands-free, inductive chargers would be ideal, but energy efficiency suffers. We asked whether the precise parking alignment provided by self-driving cars could be used to provide convenient inductive charging with improved charging efficiencies. To answer this question, we split an inductor-inductor-capacitor (LLC) battery charger at the middle of the isolation transformer. The power factor correction, tank elements, and transformer primary windings are stationary, while the transformer secondary, rectifiers, and battery control logic are on the vehicle. The transformer is assembled each time the EV parks.
2017-03-28
Journal Article
2017-01-1221
Shingo Soma, Haruhiko shimizu, Eiji Shirado, Satoshi Fujishiro
Abstract As heavy rare earth elements are become less prevalent, because one-tenth as often in ore deposits as light rare earth elements. Future usage of need to be reduces heavy rare earth, because of resource risks and costs. As such, a method was developed to recover reductions in coercive force and prevent demagnetization temperature from reducing without adding any heavy rare earth elements. First, a heavy rare-earth-free magnet was developed by hot deformation, which limits growth of crystal grain size, and relationships were clarified between coercive force and optimal deforming temperatures, speed, and total rare earth amounts for heavy rare-earth-free magnets. Second, it was made clear that the permeance coefficient can be increased by reshaping the flux barriers, and that the developed hot deformed magnet can be adopted.
2017-03-28
Technical Paper
2017-01-1224
Ryota Kitamoto, Shinnosuke Sato, Hiromichi Nakamura, Atsushi Amano
Abstract A new fuel cell voltage control unit (FCVCU) has been developed for a new fuel cell vehicle (FCV). In order to simultaneously reduce the electric powertrain size and increase the driving motor power, the FCVCU is needed to boost the voltage supplied from the fuel cell (FC) stack to the driving motor. The FCVCU circuit configuration has four single-phase chopper circuits arranged in parallel to form a 4-phase interleaved circuit. The intelligent power module (IPM) is a full SiC IPM, the first known use to date in a mass production vehicle, and efficiency has been enhanced by making use of the effects of the increased frequency to reduce both the size of the unit and the loss from passive parts. In addition, a coupled inductor was used to reduce the inductor size. As a result, the inductor volume per unit power was reduced approximately 30% compared to the previous VCU inductor.
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
2017-01-1225
Jayaraman Krishnasamy, Martin Hosek
Abstract An advanced electric motor with hybrid-field topology has been developed for automotive traction applications. Departing from the conventional radial- and axial-field designs, the hybrid-field motor features three-dimensional magnetic flux paths, which are enabled by a novel isotropic soft magnetic material produced by a unique additive-manufacturing process based on spray forming. The motor is expected to offer an unprecedented combination of high power output, compact size, low weight and energy efficiency, achieving more than two times higher power density than state-of-the-art high-performance traction motors.
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
2017-01-1232
Tsubasa Yamazakii, Hidekazu Uchiyama, Kazuaki Nakazawa, Tsubasa Isomura, Hisashi Ogata
Abstract Solar car races are held worldwide, aiming to promote vehicles that help reduce environmental loads on the roads. In order to gain superiority in solar car racing, it is essential to develop a high efficiency brushless direct drive motor that optimizes the energy use to the fullest and allows high speed driving when needed. To achieve these goals, two development approaches of solar car motors are proposed: the high efficiency motor which improves electrical characteristics and significantly reduces energy loss; and the variable field magnet motor that offers instant speed boost for a temporary period of time for overtaking opponents. We have developed a high efficiency motor through the application of an amorphous core and laminated magnets. Instead of the standard method of the W-EDM (Wire-Electric Discharge Machining) for amorphous cores, we utilized water jet cutting, through which we succeeded in achieving insulation between laminated cores.
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
2017-01-1236
Shuitao Yang, Lihua Chen, Mohammed Khorshed Alam, Fan Xu, Yan Zhou
Abstract A hybrid electric vehicle (HEV) can utilize the electromechanical path to optimize the ICE operation and implement the regenerative brake, the fuel economy of a vehicle therefore gets improved significantly. Bi-directional Boost converter is usually used in an electric drive system to boost the high voltage (HV) battery voltage to a higher dc-link voltage. The main advantages for a system with Boost converter is that the traction inverter is de-coupled from battery voltage variations causing it to be over-sized. When designing this Boost converter, the switching frequency is a key parameter for the converter design. Higher switching frequency will lead to higher switching loss of power device (IGBT +diode), moreover, it has significant impact on inductor ripple current, HV battery ripple current and input capacitor current. Therefore, the switching frequency is one of the most important parameters for the design and selection of both active and passive components.
2017-03-28
Technical Paper
2017-01-1235
Baoming Ge, Lihua Chen, Shuitao Yang
Abstract Electric vehicles (EV) and hybrid electric vehicles (HEV) require high torque/acceleration ability and wide speed range. To meet both of them, the traction machines usually have to be oversized, which results in high volume and weight, high cost, and low efficiency. In practical application, high speed motors combining with gear box provide the expected torque and speed capability. If pole-changing machines are employed to achieve wide torque and speed ranges, gear box and motor size can be reduced in EVs/HEVs. This paper presents a pole-phase modulation motor drive which changes both of poles and phases simultaneously, as a result that the motor extends its torque/speed capability in a flexible way. Simulation results verify the principle and control method for this kind of motor drives.
2017-03-28
Technical Paper
2017-01-1241
Wei Zhang, Rajesh Malhan
Abstract Wireless power transfer (WPT) technology has started to be applied in charging electrical vehicles (EV). EV models with built-in wireless charging capability is expected to be available from several major automakers in the next few years. Meanwhile, problems associated with the massive adoption of automobiles require new format of vehicles, especially the form with compact size and electric power. An inductively charged autonomous bicycle (iCab) is proposed, which has both the automotive driving and wireless charging features. It is designed to be compatible with an EV wireless charger. The wireless charging interoperability issue of the single transmitting coil capable to charge both the EV and iCab is studied in this paper. The receiving coil of a wireless charger is usually designed to match with single transmitting coil and to have a fixed power level output.
2017-03-28
Technical Paper
2017-01-1246
Fan Xu, Lihua Chen, Shuitao Yang, Yan Zhou, Mohammed Khorshed Alam
Abstract Power modules play a key role in traction inverters for vehicle electrification applications. The harsh automotive operating environment is a big challenge for power modules. The paper highlights the challenges for power modules usage in electrified vehicles (xEVs), and proposes a design verification procedure for such application in order to ensure the reliable operation under all conditions. First, power modules operate in all climate zones and are exposed to a wide ambient temperature range underhood from -40°C to 105°C. A typical automotive power module should therefore withstand a junction temperature from -40°C to up to 175°C without exceeding its safe operating area (SOA), e.g. avalanche breakdown voltage, maximum current, and thermal limit. Second, an inductive induced high voltage spike could be generated during the power semiconductor fast switching at high voltage and high current conditions.
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
2017-01-1252
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
2017-01-1256
Mayank Garg, Christopher Rahn
Abstract Lithium ion (Li-ion) battery capacity selection for hybrid electric vehicles (HEVs) is primarily based on charge/discharge power and life. At high temperatures, battery degradation increases and reduces battery life, but battery internal resistance reduces and improves battery performance. Lithium ion phosphate (LFP) batteries have a maximum allowable voltage limit based on degradation minimization, so the battery capacity is selected large enough to stay within the limit over the entire life of the pack. This paper develops an optimal temperature trajectory for LFP cells to improve their charge acceptance and reduce HEV pack size while maintaining battery life. The proposed algorithm has two strategies. First, the battery pack temperature is increased when its state of charge (SOC) is high because the cell is more likely to exceed maximum voltage limit at high SOC.
2017-03-28
Technical Paper
2017-01-1255
Zhihong Wu, Ke lu, Yuan Zhu, Xiaojun Lei, Liqing Duan, Jian_ning Zhao
Abstract Permanent magnet synchronous motors (PMSM) are widely used in the electric vehicles for their high power density and high energy efficiency. And the motor control system for electric vehicles is one of the most critical safety related systems in electric vehicles, because potential failures of this system can lead to serious harm to humans’ body, so normally a high automotive safety integrity level (ASIL) will be assigned to this system. In this paper, an ASIL-C motor control system based on a multicore microcontroller is presented. At the same time, due to the increasing number of connectivity on the vehicle, secure onboard communication conformed to the AUTOSAR standard is also implemented in the system to prevent external attacks.
2017-03-28
Technical Paper
2017-01-1254
Raja Sangili Vadamalu, Christian Beidl
Powertrain systems exploiting information from vehicle connectivity have widened the system boundary resulting in additional degrees-of-freedom for predictive trajectory planning. Heuristic methods based on component characteristics are currently widely used for Energy Management (EM) functionality of hybridized powertrains. Despite their better usability, increased calibration effort and sensitivity to synthetic calibration scenarios are drawbacks of such control methods. Availability of predictive data, better computing power and challenges posed by various scenarios in real driving, have led to interest in online-optimizing EM functionality. Equivalent Consumption Minimization Strategy (ECMS) approaches based on Indirect optimal control /Pontryagin Minimum principle have difficulty in handling inequality state constraints. Extensions of ECMS make use of modifications to the equivalence factor/co-state, based on prediction of driving conditions.
2017-03-28
Technical Paper
2017-01-1253
Somnath Sengupta, Chethan Gururaja, Sushant Hingane, Prajwal A K, Malay Maniar, Ondřej Mikuláš, Jaroslav Pekar
Abstract Increasingly strict CO2 and emissions norms are pushing the automotive industry towards increasing adoption of Hybrid Electric Vehicle (HEV) technology. HEVs are complex hardware systems which are often controlled by software that is complex to maintain, time-consuming to calibrate, and not always guaranteed to deliver optimal fuel economy. Hence, coordinated, systematic control of different subsystems of HEV is an attractive proposition. In this paper, Model Predictive Control (MPC) and Equivalent Consumption Minimization Strategy (ECMS) based supervisory controllers have been developed to coordinate the power split between the two prime movers of an HEV – internal combustion engine and electric motor. A dynamical physics based HEV model has been developed for simulation of the system behavior. A cost function has been formulated to improve fuel economy and battery life.
2017-03-28
Technical Paper
2017-01-1260
Gianmarco Galmarini, Stefano Dell'Agostino, Massimiliano Gobbi, Giampiero Mastinu
Abstract Apollo is the name of a solar prototype vehicle of Politecnico di Milano (Technical University of Milan) that has been conceived and employed for the Shell Eco-marathon® Europe competition (SEM). The paper introduces the concept design, the detailed design, the construction, the indoor tests, the successful employment at SEM and the end-of-life of the prototype. Apollo is a three-wheeler with a single driving and steering wheel at the rear. A wing with solar cells provides part of the electric energy required for running. The conceptual design started from the accommodation of the driver inside the vehicle. A number of iterations focusing on CFD (computation fluid dynamics) and wind-tunnel tests allowed to refine the total drag to less than 2N at 35 km/h. The tyre characteristic was measured on a drum. The camber of front wheels was set to 4 deg which provided the least rolling resistance.
2017-03-28
Technical Paper
2017-01-1259
Eduardo D. Marquez, John Stevenson, Ethan Dietrich, Douglas Nelson, Christopher Flake, Alexander Neblett, Samuel Reinsel
Abstract The Hybrid Electric Vehicle Team of Virginia Tech (HEVT) is currently modeling and bench testing powertrain components for a parallel plug-in hybrid electric vehicle (PHEV). The custom powertrain is being implemented in a 2016 Chevrolet Camaro for the EcoCAR 3 competition. The engine, a General Motors (GM) L83 5.3L V8 with Active Fuel Management (AFM) from a 2014 Silverado, is of particular importance for vehicle integration and functionality. The engine is one of two torque producing components in the powertrain. AFM allows the engine to deactivate four of the eight cylinders which is essential to meet competition goals to reduce petroleum energy use and greenhouse gas emissions. In-vehicle testing is performed with a 2014 Silverado on a closed course to understand the criteria to activate AFM. Parameters required for AFM activation are monitored by recording vehicle CAN bus traffic.
2017-03-28
Technical Paper
2017-01-1258
John Catton, Caixia Wang, Steven Sherman, Michael Fowler, Roydon Fraser
Abstract The automobile industry has been undergoing a transition from fossil fuels to a low emission platform due to stricter environmental policies and energy security considerations. Electric vehicles, powered by lithium-ion batteries, have started to attain a noticeable market share recently due to their stable performance and maturity as a technology. However, electric vehicles continue to suffer from two disadvantages that have limited widespread adoption: charging time and energy density. To mitigate these challenges, vehicle Original Equipment Manufacturers (OEMs) have developed different vehicle architectures to extend the vehicle range. This work seeks to compare various powertrains, including: combined power battery electric vehicles (BEV) (zinc-air and lithium-ion battery), zero emission fuel cell vehicles (FCV)), conventional gasoline powered vehicles (baseline internal combustion vehicle), and ICE engine extended range hybrid electric vehicle.
2017-03-28
Technical Paper
2017-01-1257
Haotian Wu
Abstract Previous studies have investigated various hybrid and electric powertrain architectures to balance concerns about the energy consumption and drivability. However, present architectures have some intrinsic drawbacks on the powertrain torque winding up, weight, packaging and energy harvest. This study proposed an electric powertrain that is powered by four independent motor drive. In order to investigate the drivability and regeneration braking performance, physics-based models of vehicle, motor and battery were developed; meanwhile, the dual-loop feedforward motor control and hybrid sliding mode control were presented. The Physics model-based evaluation was conducted by using the co-simulation technology of LMS AMESim and Simulink. The results show that the proposed four-wheel independent electric powertrain can achieve better drivability and regeneration braking performance. The proposed hybrid sliding mode control can converge faster than the bang-bang control.
2017-03-28
Technical Paper
2017-01-1261
Mark Woodland, Dillon Savage, Patrick Paulus, Aaron Eliason, Cade Smith, Dan Cordon, Steven W. Beyerlein
Abstract The University of Idaho has sponsored entries in the Collegiate Design Series (CDS) Clean Snowmobile Competition since 2001. During this period, a topic of ongoing concern among its student leaders is project and knowledge management. The need for holistic implementation of specific methods/tools is underscored by survey feedback from current CDS teams and University of Idaho alumni, many now employed in the automotive/motorsports industry. This paper details local implementation of nine developmentally appropriate practices for CDS teams composed of students at multiple levels in their academic study (underclassmen, seniors, and graduate students).
2017-03-28
Journal Article
2017-01-1295
Andres Toledo, Rodrigo Felix
Abstract Political and social trends in the automotive industry production and consumption have changed in the last decade, driving a demand for more efficient, low-fuel consuming, clean vehicles in most markets nowadays. Recently the demand for such vehicles has been increasing and emerging markets are no exception; automakers all around the world have invested heavily in developing new electrification technologies that would comply with the newer and stricter regulations and environmental policies, being Start-Stop systems one of the preferred approaches due to their lower complexity and cost compared to full and mild hybrids. Mexico stands out as a challenge for the implementation of this technology due to its wide range of altitudes, temperatures, traffic jams, and some other contributing factors that can hinder this type of application – especially in its bigger and more populated cities.
2017-03-28
Technical Paper
2017-01-1304
Alejandro Rosas Vazquez, Fernando Paisano, Diego Santillan Gutierrez
Abstract For many years, the use of in-mold fasteners has been avoided for various reasons including: not fully understanding the load cases in the part, the fear of quality issues occurring, the need for servicing, or the lack of understanding the complexity of all failure modes. The most common solution has been the use of secondary operations to provide attachments, such as, screws, metal clips, heat staking, sonic welding or other methods which are ultimately a waste in the process and an increase in manufacturing costs. The purpose of this paper is to take the reader through the design process followed to design an in-molded attachment clip on plastic parts. The paper explores the design process for in-molded attachment clips beginning with a design concept idea, followed by basic concept testing using a desktop 3D printer, optimizing the design with physical tests and CAE analysis, and finally producing high resolution 3D prototypes for validation and tuning.
2017-03-28
Technical Paper
2017-01-1303
Nobuhisa Yasuda, Shinichi Nishizawa, Maiko Ikeda, Tadashi Sakai
Abstract The purpose of this study is to validate a reverse engineering based design method for automotive trunk lid torsion bars (TLTB) in order to determine a free, or unloaded, shape that meets a target closed shape as well as a specified torque. A TLTB is a trunk lid component that uses torsional restoring force to facilitate the lifting open of a trunk lid, as well as to maintain the open position. Bend points and torque of a TLTB at a closed trunk position are specified by a car maker. Conventionally, a TLTB supplier determines bend points of the free shape by rotating the given bend points from a closed position around a certain axis to satisfy the specified torque at the closed position. Bend points of a deformed TLTB shape in the closed position often do not match the target bend points given by a car maker when designed by the conventional method, which can potentially cause interference issues with surrounding components.
2017-03-28
Technical Paper
2017-01-1298
Kamlesh Yadav, Abhishek Sinha, Rajdeep Singh Khurana
Abstract Vehicle Hood being the face of a passenger car poses the challenge to meet the regulatory and aesthetic requirements. Urge to make a saleable product makes aesthetics a primary condition. This eventually makes the role of structure optimization much more important. Pedestrian protection- a recent development in the Indian automotive industry, known for dynamics of cost competitive cars, has posed the challenge to make passenger cars meeting the regulation at minimal cost. The paper demonstrates structure optimization of hood and design of peripheral parts for meeting pedestrian protection performance keeping the focus on low cost of ownership. The paper discusses development of an in-house methodology for meeting Headform compliance of a flagship model of Maruti Suzuki India Ltd., providing detailed analysis of the procedure followed from introduction stage of regulatory requirement in the project to final validation of the engineering intent.
2017-03-28
Technical Paper
2017-01-0520
Gianluca Montenegro, Augusto Della Torre, Tarcisio Cerri, Angelo Onorati, Lorenzo Nocivelli, Marco Fiocco
Abstract In this work an integration between a 1D code (Gasdyn) with a CFD code (OpenFOAM®) has been applied to improve the performance of a Moto3 engine. The four-stroke, single cylinder S.I. engine was modeled, in order to predict the wave motion in the intake and exhaust systems and to study how it affects the cylinder gas exchange process. The engine considered was characterized by having an air induction system with integrated filter cartridge, air-box and intake runner, including two fuel injectors, resulting in a complex air-path from the intake mouth to the intake valves, which presents critical aspects when a 1D modeling is addressed. The exhaust and intake systems have been optimized form the point of view of the wave action. However, due to the high revolution speed reached by this type of engine, the interaction between the gas stream and the fuel spray becomes a key aspect to be addressed in order to achieve the best performance at the desired operating condition.
2017-03-28
Technical Paper
2017-01-0509
Jyotishman Ghosh, Andrea Tonoli, Nicola Amati
Abstract This paper presents a novel strategy for the control of the motor torques of a rear wheel drive electric vehicle with the objective of improving the lap time of the vehicle around a racetrack. The control strategy is based upon increasing the size of the friction circle by implementing torque vectoring and tire slip control. A two-level nested control strategy is used for the motor torque control. While the outer level is responsible for computing the desired corrective torque vectoring yaw moment, the inner level controls the motor torques to realize the desired corrective torque vectoring yaw moment while simultaneously controlling the wheel longitudinal slip. The performance of the developed controller is analyzed by simulating laps around a racetrack with a non-linear multi-body vehicle model and a professional human racing driver controller setting.
2017-03-28
Journal Article
2017-01-0622
Sury Janarthanam, Sarav Paramasivam, Patrick Maguire, James Gebbie, Douglas Hughes
Abstract Hybrid Electric Vehicles (HEV) utilize a High Voltage (HV) battery pack to improve fuel economy by maximizing the capture of vehicle kinetic energy for reuse. Consequently, these HV battery packs experience frequent and rapid charge-discharge cycles. The heat generated during these cycles must be managed effectively to maintain battery cell performance and cell life. The HV battery pack cooling system must keep the HV battery pack temperature below a design target value and maintain a uniform temperature across all of the cells in the HV battery pack. Herein, the authors discuss some of the design points of the air cooled HV battery packs in Ford Motor Company’s current model C-Max and Fusion HEVs. In these vehicles, the flow of battery cooling air was required to not only provide effective cooling of the battery cells, but to simultaneously cool a direct current high voltage to low voltage (DC-DC) converter module.
Viewing 271 to 300 of 19895