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2017-04-11
Journal Article
2017-01-9625
Souhir Tounsi
Abstract In this paper, we present a design and control methodology of an innovated structure of switching synchronous motor. This control strategy is based on the pulse width modulation technique imposing currents sum of a continuous value and a value having a shape varying in phase opposition with respect to the variation of the inductances. This control technology can greatly reduce vibration of the entire system due to the strong fluctuation of the torque developed by the engine, generally characterizing switching synchronous motors. A systemic design and modelling program is developed. This program is validated following the implementation and the simulation of the control model in the simulation environment Matlab-Simulink. Simulation results are with good scientific level and encourage subsequently the industrialization of the global system.
2017-03-28
Technical Paper
2017-01-0620
Chandrakant Parmar, Sethuramalingam Tyagarajan, Sashikant Tiwari, Ravindra Thonge, S Arun Paul
The engine compartment of passenger car application contain various source which radiates the produced heat and raises the temperature level of the compartment. The rise in compartment temperature increases the individual component body temperature. The rise in body temperature of critical components can endanger the life or functionality of the specific component or a system in which it operates. The aim of this paper is to strategise thermal protection of the rear mounted engine and it's components of a vehicle having radiator and cooling fan mounted in front. An additional ventilation fan with speed sensor is fitted alongside rear mounted engine and a unique monitoring technique framed in the EMS ECU to protect critical components like HT cables, alternators, ECU, wiring harness etc. from thermal damage. The EMS continuously monitors the engine speed, vehicle speed and the PWM signal of ventilation fan to ensure the intended operation of the ventilation fan.
2017-03-28
Technical Paper
2017-01-0628
Rahul Fageria, Satvik Jain
Turbochargers have become an inevitable part of modern engines for their ability to improve an engine's efficiency and power output through forced induction using the exhaust gas energy which otherwise would have been wasted. And with their use, there is always some unwanted heat as a by-product. For that, turbo intercoolers are employed, they reduce the temperature of the forced air before reaching the engine and improve their volumetric efficiency by increasing intake air charge density through an isobaric cooling. The forced air produced by the turbocharger is routed through the intercooler where its temperature is reduced before reaching the engine. Intercoolers also eliminate the need for using the wasteful method of lowering intake charge temperature by the injection of excess fuel into the cylinders' air induction chambers, to cool the intake air charge, prior to its flowing into the cylinders.This has made modern heavy duty diesel vehicles far more efficient.
2017-03-28
Technical Paper
2017-01-1184
Kiyoshi Handa, Shigehiro Yamaguchi, Kazuya Minowa, Steven Mathison
Fuel cell automobiles are already on the market, and construction of hydrogen refueling stations is proceeding. Meanwhile, fuel cell motorcycles are still in the development stage, and it is necessary to develop a hydrogen refueling method for motorcycles. Automobiles and motorcycles should be able to share hydrogen refueling stations in the same manner as gasoline stations in order to reduce investment into infrastructure construction. However, the hydrogen vessel capacity of motorcycles is only a fraction that of automobiles, so the flow rate is too small and adjustment is a challenge when using a refueling method with a fixed pressure ramp rate, such as that of the automobile refueling standard. In addition, there are a number of issues for using the same refueling method as automobiles, such as cases in which the vessel becomes full simply by the refueling for initial pressure detection. For these reasons, it is a challenge to share hydrogen refueling stations with automobiles.
2017-03-28
Technical Paper
2017-01-0629
John Kuo, George Garfinkel
Detailed thermal modeling of liquid-cooled vehicle traction battery assemblies using Computational Fluid Dynamics (CFD) analysis techniques usually involves large models to accurately resolve small cooling channel details. For large battery packs, some of these meshes may exceed current computational capabilities or result in long and expensive computational efforts. Moreover, only steady-state thermal predictions are usually performed, as drive-cycle transient simulations become impractical due to the exceedingly long solving times. To tackle this problem, an innovative segregated method has been developed for thermal analysis of liquid-cooled traction batteries, where battery cells and their active cooling system are divided into three parts: the cell, the cold plate and the interface between them.
2017-03-28
Technical Paper
2017-01-0624
Jiaxin Liu, Sicheng Qin, Yankun Jiang, Shumo He
In this work, a XD132 Road Roller from XCMG in China was employed as the research basis to study the heat exchange performance for the heat dissipation module under varied working conditions. The module in XD132 consists of a cooling fan and a radiator group. At first, a numerical investigation on the elementary unit of the radiator was performed to obtain Colburn j factor and Fanning f factor, which was used for the -NTU method that predicts the radiator performance. The fan was numerically tested in a virtual tunnel to acquire the performance curve. The performance data from both investigations were transformed into the boundary conditions for the numerical model in a virtual tunnel. A field experiment was carried out to validate the simulation accuracy, and the performance regularity under four working conditions were discussed.
2017-03-28
Technical Paper
2017-01-1183
Kenneth Johnson, Michael J. Veenstra, David Gotthold, Kevin Simmons, Kyle Alvine, Bert Hobein, Daniel Houston, Norman Newhouse, Brian Yeggy, Alex Vaipan, Thomas Steinhausler, Anand Rau
Fuel cell vehicles are entering the automotive market with significant potential to reduce harmful greenhouse emissions, facilitate energy security, and increase efficiency while providing expected driving range and fill times. One of the challenges for the successful commercialization of this technology is transitioning the on-board fuel system from gasoline as a liquid to hydrogen as a compressed gas. In order to reduce the energy density gap, hydrogen needs to be compressed to 700 bar, which still requires 7 times greater volume in comparison to gasoline. The improved efficiency of a fuel cell vehicle can assist in reducing the required volume increase to 4 times for an equivalent driving range. Based on need to store high pressurized hydrogen, it should be evident that a hydrogen tank requires a specialized structural pressure vessel, significantly different in function from a gasoline container.
2017-03-28
Technical Paper
2017-01-0627
Bo Yang, Peter Woyciesjes, Aleksei Gershun
In this paper, new test results in the use of electrochemical techniques to measure corrosion in extended life engine coolants are presented. Corrosion protection performance of the engine coolants (including both fresh coolants and simulated used coolants) for typical cooling system metals under heat rejecting surface and heat accepting surface corrosion conditions for both general corrosion and localized corrosion are measured under conditions similar to the ones encountered in vehicle engine cooling systems as a function of immersion time. Fleet test of the coolants were also conducted. They are used to provide technical support on the electrochemical test methodologies adopted. The effective use of electrochemical techniques to aid the development of the next generation of extended life coolant technologies with improved corrosion protection performance and a longer service life will be demonstrated and discussed.
2017-03-28
Technical Paper
2017-01-0622
Sury Janarthanam, Douglas Hughes, James Gebbie, Patrick Maguire, Sarav Paramasivam
Hybrid vehicles utilize a high voltage battery pack to improve fuel economy by maximizing the capture of vehicle kinetic energy for reuse. Consequently, these batteries experience frequent and rapid charge-discharge cycles. The heat generated during these cycles must be managed effectively to maintain battery cell performance as well as pack life. The battery cooling system must keep the pack temperature below a design target and approximately uniform across all cells in the pack. Here, the authors discuss some of the design points of the air cooled battery packs in Ford’s current model Fusion and C-Max hybrids. In these vehicles, flow of battery cooling air was required to not only provide effective cooling of the battery cells, but to simultaneously cool a DC-to-DC (high to low DC voltage) converter module.
2017-03-28
Technical Paper
2017-01-1227
Ali Najmabadi, Michael Kress, Brett Dryer, Ahmad Khan
This abstract studies different switching schemes for loss reduction in a traction motor drive. The system under examination is composed of a battery, a 2 level Voltage Source Inverter, and an Interior Permanent Magnet motor. Discontinuous PWM (DPWM) control strategy is widely used in this type of motor drive for the reduction of losses. In some publications, the effect of the DPWM modulation scheme is compared to the reduction of the switching frequency which causes a drop in switching losses of the inverter. Similarly, extensive studies have examined the effect of variation of the switching frequency on the motor and inverter losses. However, the effect of applying both switching schemes simultaneously has not been explored. This paper will use a system that is operated at a fixed switching frequency as the base line. Afterwards, three different switching schemes will be studied and compared to the base line.
2017-03-28
Technical Paper
2017-01-1247
Mohammed Khorshed Alam, Lihua Chen, Yan Zhou, Fan Xu, Shuitao Yang
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. The 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. Inverters introduce voltage oscillation in the DC-link terminal during battery charging through regenerative operation and results in unwanted power oscillation through the bypass diode. Both of these phenomena have been investigated in details.
2017-03-28
Technical Paper
2017-01-0631
David Ogbuaku, Timothy Potter, James M. Boileau
The competing demands for weight reduction and high performance in modern automobiles mean that manufacturers must use engines with smaller displacements and higher power outputs. Compared to past engine designs, this combination inherently generates more heat that must be removed to ensure the durability of the engine. This situation has led to the need for radiator and other heat-exchanger systems that can reduce weight while maintaining the engine at acceptable operating temperature limits. Further, the desire for more fuel efficient vehicles and lower emissions footprints has led to smaller, more aerodynamic frontend designs in modern automobiles. Therefore, the area available in the engine compartment to mount the heat exchangers has become smaller while the number and size of the heat exchangers required to adequately cool the engine have increased.
2017-03-28
Technical Paper
2017-01-0893
Marek Tatur, Kiran Govindswamy, Dean Tomazic
Demanding CO2 and fuel economy regulations are continuing to pressure the automotive industry into considering innovative powertrain and vehicle-level solutions. Powertrain engineers continue to minimize engine internal friction and transmission parasitic losses with the aim of reducing overall vehicle fuel consumption. Strip friction methods are used to determine and isolate components in engines and transmissions with the highest contribution to friction losses. However, there is relatively little focus on friction optimization of Front-End-Accessory-Drive (FEAD) components such as alternators and AC compressors. This paper will outline the development of a flexible test stand that allows for highly accurate torque measurements on such components under precisely controlled environmental boundary conditions and device loads.
2017-03-28
Technical Paper
2017-01-0001
Ming Cheng, Bo Chen
This paper studies the hardware-in-the-loop (HiL) design of a power-split hybrid electric vehicle (HEV) for the research of HEV lithium-ion battery aging. In this paper, an electrochemical model of a lithium ion battery pack with the characteristics of battery aging, is built and integrated into the vehicle model of Autonomie® software from Argonne National Laboratory. The vehicle model, together with the electrochemical battery model, is designed to run in a dSPACE real-time simulator while the powertrain power is managed by a dSPACE MicroAutoBoxII hardware controller. The control interface is designed using dSPACE ControlDesk to monitor the real-time simulation results. The HiL simulation results with the performance of vehicle fuel economy and dynamics, the thermal aging of the battery are presented and analyzed.
2017-03-28
Technical Paper
2017-01-0317
James Henry Wrock, Pengying Niu, Huairui Guo
Automobiles have a high degree of mechanical and electrical complexity. Product complexity has the accompanying effect of requiring high levels of design and process complicatedness. The net result is a product development process which is prone to “creating failures”. These failures typically have their origin in an overall lack of complete understanding of the system in terms of materials, geometries and energy flows. Despite all of the engineering intentions “mistakes” are inevitably, common and must be dealt with accordingly. In the worst case, if a mistake manifests itself into a product failure mode the customer may have a negative experience. Therefore, it is imperative that once a mistake surfaces that design engineers, suppliers along with reliability professionals assess the associated risk. One approach to assess risk is the use of degradation analysis.
2017-03-28
Technical Paper
2017-01-0398
Robert A. Smith, Allison Ward, Daniel Brintnall
Utilization of TGA Flynn-Wall and Arrhenius Analysis for Rapid Prediction of Automotive PVC Cable Performance Robert Alan Smith, Allison Ward, and Daniel D. Brintnall Delphi Electrical/Electronic Architecture 4551 Research Parkway Warren, Ohio 44483 Poly(vinylchloride), PVC, insulated cable was first used in automobiles in the 1940’s when the average vehicle contained 40 meters of wiring. Presently, the Bentley Bentayga has a wiring harness that weighs 110 lbs! Indeed, the electrical systems of automobiles have become much more complicated than just provision of lighting, signaling, and heat with the evolution of climate control, infotainment and data delivery systems. Due to low cost and light weight, PVC insulated cable is still the most widely used cable in automobiles and is found predominantly in non-engine compartment applications limited by an upper use temperature of 80◦ C.
2017-03-28
Technical Paper
2017-01-0626
LeeAnn Wang, George Garfinkel, Ahteram Khan, Mayur Harsha, Prashanth Rao
When a driver completes an aggressive drive cycle on a hybrid vehicle, the High Voltage (HV) battery system may risk exceeding the power limit temperature, due to continuous absorption of radiative and convective heat from the exhaust and pavement, even after key-off. In such case, the vehicle may not be keyed-on after a certain time. A transient thermal analysis is conducted on a HV battery system to simulate the key-off operation using Computational Fluid Dynamics (CFD). The analysis is partitioned into two stages, due to complex geometry and multiple phenomena captured in the model. The first stage involves two steady-state simulations. The first simulation is to model the HV battery system, during an aggressive drive cycle. The second simulation is to model the vehicle at an idle condition immediately after the aggressive drive cycle.
2017-03-28
Technical Paper
2017-01-1219
Steven G. Rinaldo, Zhihong Jin, Perry Wyatt
Validating the state-of-function (SOF) algorithm is critical for battery management as it is responsible for battery power utilization as well as safety protection and life. The SOF accomplishes this optimization task by communicating battery level operational limits related to power, current, voltage and temperature. Ultimately these operational limits are predicted via parameters derived from component models. Correspondingly, any errors within the component models will propagate into the reported SOF limits. Developing an efficient SOF validation methodology will facilitate the understanding of SOF performance gaps. In this work, we developed a methodology that consists of simulating the cell model response and SOF output for a set of current pulse events that span operational boundaries defined by temperature, initial state-of-charge, pulse time and current magnitude.
2017-03-28
Technical Paper
2017-01-1191
Patrick Wesskamp, Simon Reitemeyer, Joachim Melbert
Lithium-Ion cells are currently the most favored energy storage technology for Hybrid and Electrical vehicles. A reliable prediction of the electrical driving range is a crucial criterion for customer acceptance of this new technology. For a given cell technology accurate algorithms are needed for on-board estimation of current state-of-charge and capacity of the battery. From this, remaining driving range and the battery state-of-health can be derived. Online estimation of the battery capacity is complicated due to variation of electrical battery behavior with capacity and resistance degradation, temperature variation as well as limited measurement accuracy of the battery management unit. In this paper, a long-term aging study performed on more than 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.
2017-03-28
Technical Paper
2017-01-1197
Aziz Abdellahi, Brian Sisk, Saeed Khaleghi Rahimian, Berislav Blizanac
48V battery packs, with rated power capabilities up to 16kW, are rapidly becoming a new standard in the automotive industry. Improving on their 12V counterparts (2-5kW), 48V Mild Hybrid Electric Vehicles (MHEV) allow for extended start-stop and regenerative braking functionalities, providing fuel economy benefits of up to 10-15% in standard passenger vehicles. New and relatively unexplored opportunities exist to further increase the fuel economy performance of 48V systems. Such capabilities include electric supercharging, electric boost, electric power steering, electric suspension and electric air conditioning (AC). Improvement in battery power (20kW or higher) would further enable hybridization to near-HEV levels as well as engine downsizing, thus paving the way to fuel economy improvements beyond the current 10-15% MHEV limit. Such novel capabilities require the development of 48V battery packs with a high power-to-energy ratio.
2017-03-28
Technical Paper
2017-01-1190
Patrick Maguire, Hyung Baek, Stephen Liptak, Olivia lomax, Rodolfo Palma, Yi Zhang
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 battery enclosure alternatives to steel and aluminum have focused on thermoset composites and glass filled polypropylene, this solution leverages HDPE design techniques established for fuel tanks and applies them to a HV battery, with some notable differences such as employing two injection molded halves which are joined via infrared welding. 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
2017-01-1195
Masahiro Kimoto
SAE standards require the function of a manual service disconnect (SD), 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 service disconnect is reviewed to meet isolation requirement of the battery pack system. Battery architectures with 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 SD 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
2017-01-1194
Qiaohua Fang, Xuezhe Wei, Haifeng Dai
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 parallel modules on EVs, 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
2017-01-1205
Letao Zhu, Xuezhe Wei, Haifeng Dai, Zechang Sun
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), state of power (SOP) and so on. In this paper, an improved battery modeling method is proposed which is based on recursive least square 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
2017-01-1198
Po Hong, Hongliang Jiang, Jian qiu Li, Liangfei Xu, Minggao Ouyang
The lithium-ion battery plays an important role in saving energy and lowering emissions. Many parameters like temperature have influence on the characteristic of the battery and in an electric vehicle this phenomenon becomes more serious. Estimating these parameters is kind of challenging work and many available approaches have been studied such as Kalman filter and offline AC impedance. In this paper, the application of a boost DC/DC converter to the battery system of high power for online AC impedance identification is proposed. The function of the converter is to inject a current fluctuation signal into the battery at work and the normal output current is drawn by a load. Through analyzing the average state space equations and deriving the small signal model of the converter, the gain function is deduced of the fluctuated current signal against the fluctuated duty cycle which controls the converter.
2017-03-28
Technical Paper
2017-01-1204
Xiao Yang, Ted Miller
We try to understand the fast recharge capability of Li-ion batteries and its effect on capacity degradation. We find out that 5 Ah prismatic Li-ion cells can be fully recharged in 3 minutes under a constant rate of 20C, or in 2 min (25.5C) from 0% to 85% SOC (state of charge) without undue stresses. We cycle the battery at 16C charge rate from 0 to 100%SOC and do not see any unexpected battery capacity loss in 50 cycles, where half of the cycles are 1C-rate charge as a reference capacity check. We realize that the batteries under the fast charge study do not experience mass transport limitations in either solid electrodes or the electrolyte system.
2017-03-28
Technical Paper
2017-01-1201
Zhenli Zhang, Zhihong Jin, Perry Wyatt
Lithium plating is an important failure factor for lithium ion battery with carbon-based anodes and therefore preventing lithium plating has been a critical consideration in designs of lithium ion battery and battery management system. The challenges are: How to determine the charging current limits which may vary with temperature, state of charge, state of health, and battery operations? Where are the optimization rooms in battery design and management system without raising plating risks? Due to the complex nature of lithium plating dynamics it is hard to detect and measure the plating by any of experimental means. In this work we developed an electrochemical model that explicitly includes lithium plating reaction. It enables both determination of plating onset and quantification of plating. We have studied the effects of charging pulses on homogenous plating in order to provide guidance for lithium ion battery design in hybrid applications.
2017-03-28
Technical Paper
2017-01-1203
Takashi Inamoto, Lawrence Alger
Recently, Almost HV, PHEV, EV veheicle use a Li-ion battery as a main battery. In case of the main battery with Li-ion battery, it is neccesarry to monitor all cell voltage in order to secure a safety of Li-ion battery. In this paper, DENSO report that new development ECU which is contributed to the reduction of system cost and the inprovement of reliability. Many semiconductor suppier develop various monitoring IC, but a measurable cell voltage number is insufficient. In order to measure many cell voltage in seriese, many monitoring ICs are needed for battery management system. So the system cost increases due to increase of IC number and insulation device. Therefore DENSO develop the monitoring IC with the original high voltage process of DENSO. This monitoring IC measures 24 cells voltage.
2017-03-28
Technical Paper
2017-01-1642
Don Price
Each of the 300 (or more) electrical connectors in a vehicle is assembled by hand. Since there is a risk of a repetitive stress injury resulting from any of these connectors, significant work has been done to determine what test needs to be performed to determine whether a connector is ergonomically safe for the person performing the assembly operation. This prior work has determined the maximum force that can be safely applied to mate a connector... what is not known is whether the mate force of a connector is influenced by the assembly speed on connector. This has significant practical interest since the preferred lab-based test speed is 50mm/min., which is ten times slower than the typical assembly speed in a vehicle assembly plant. There have been some calls for a change in the current testing method to use speeds that match typical assembly speeds.
2017-03-28
Technical Paper
2017-01-1641
Ludwig Brabetz, Mohamed Ayeb, Leonard Gysen
The mandatory usage of fuses within the electrical distribution system (EDS) has a strong impact on the cross section of the connected wires and thus on the weight and required amount of material, especially of copper. Currently, circuit breakers and, in most cases, thermal fuses are used due to their low cost and robust design. However, for future EDS architectures, the implementation of fuses using solid state switches is being considered for several reasons, e.g. resetability, diagnosis, smaller tolerances, and reduced dependancies on ambient temperature, arcing, or pulse sequences. In addition, there can be advantages on the system level, especially for higher voltages or in combination with other switch-based functionalities such as pulse width modulation, power multiplexing, or substitution of relays. Until now, smart solid state switches only emulate the behavior of thermal fuses and are therefore based on a fixed time-current data set.
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