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Viewing 1 to 30 of 17597
Technical Paper
2014-05-20
Y. Gene Liao, Molly O'Malley, Allen Quail
Fuel consumption reduction on medium-duty tactical truck has and continues to be a significant initiative for the U.S. Army. The Crankshaft-Integrated-Starter-Generator (C-ISG) is one of the parallel hybrid propulsions to improve the fuel economy. The C-ISG configuration is attractive because one electric machine can be used to propel the vehicle, to start the engine, and to be function as a generator. The C-ISG has been implemented in one M1083A1 5-ton tactical cargo truck. This paper presents the experimental assessments of the C-ISG hybrid truck characteristics. The experimental assessments include all electric range for on- and off-road mission cycles and fuel consumption for the high voltage battery charging. Stationary tests related to the charging profile of the battery pack and the silent watch time duration is also conducted.
Technical Paper
2014-05-10
Daogao Wei, Peng Wang, Zhijie Pan, Siming Hu, Huaiyang Xiao
Tie rod end clearance is an important parameter influencing automobile stability under slalom maneuver. In this paper the steering mechanism is simplified into a plane linkage mechanism and an analysis of the effects on vehicle stability exerted by kinematic pair clearance under slalom maneuver is also presented. A 4DOF mathematical model of vehicle maneuvering system is thus being built. On the basis of this model, we adopt the numerical analysis method to conduct a simulated analysis about the stability of prototype vehicle side slip angle as the clearance parameter changes. According to the results, vehicle slalom dynamics behaviors manifest itself in shifting from single cycle to chaos directly. With the increase in clearance, nearly no change is displayed in the upper critical frequency of vehicle slalom instability. However, an increasing rise is shown in the lower critical frequency. The instability frequency bandwidth, accordingly, bears an increase as well and a marked difference manifests itself with regard to the characteristics of window dynamics in chaotic areas.
Technical Paper
2014-05-10
Hyeonu Heo, Jaehyung Ju, Doo Man Kim, Harkbong Kim
An understanding of the flow around a tire in contact with the ground is important when designing fuel-efficient tires as the aerodynamic drag accounts for about one third of an entire vehicle's rolling loss. Recently, non-pneumatic tires (NPTs) have drawn attention mainly due to their low rolling resistance associated with the use of low viscoelastic materials in their construction. However, an NPT's fuel efficiency should be re-evaluated in terms of aerodynamic drag: discrete flexible spokes in an NPT may cause more aerodynamic drag, resulting in greater rolling resistance. In this study, the aerodynamic flow around a non-pneumatic tire in contact with the ground is investigated for i) stationary and ii) rotating cases using the steady state Reynolds-Averaged Navier-Stokes (RANS) method. A sensitivity analysis was carried out with a varying mesh density. The flow into cavity by the discrete spoke geometry of the NPT does not significantly affect the overall aerodynamic drag.
Technical Paper
2014-05-09
Francisco Soriano, Jesus Alvarez-Florez, Manuel Moreno-Eguilaz
This paper presents a novel methodology to develop and validate fuel consumption models of Refuse Collecting Vehicles (RCVs). The model development is based on the improvement of the classic approach. The validation methodology is based on recording vehicle drive cycles by the use of a low cost data acquisition system and post processing them by the use of GPS and map data. The corrected data are used to feed the mathematical energy models and the fuel consumption is estimated. In order to validate the proposed system, the fuel consumption estimated from these models is compared with real filling station refueling records. This comparison shows that these models are accurate to within 5%.
Technical Paper
2014-04-01
Arturo Davila, Emilia Romero, Marina Roche, Marco Mammetti, Javier Gutierrez, Micha Lesemann
Abstract The ELVA project (Advanced Electric Vehicle Architectures) was co-funded under the European Commission's 7th Framework Programme and had the goal of developing vehicle architectures specifically designed for electric powered vehicles. The consortium was formed by the Institute for Automotive Engineering (ika) of RWTH Aachen University (coordinator), Applus+ IDIADA, Volkswagen, Renault, Centro Richerche Fiat (CRF), Continental and the Swedish Vehicle and Traffic Safety Centre (SAFER). The main objectives of the ELVA project were: To generate, investigate and analyze innovative design concepts for EVs To deliver a wide range of advanced modular architectures that enable the same level of safety as today's best known practices To minimize weight, maximize energy efficiency, optimize ergonomics and space at affordable costs with good levels of comfort and performance To deliver best practices and evidence based design rules for modular lightweight and safe architectures specifically for EVs The project, which was characterized by an intensive interaction among the partners, completed the design of three electric vehicle concepts, that were developed in parallel and doing iterative design loops.
Technical Paper
2014-04-01
Eric W. Chow, John B. Heywood, Raymond L. Speth
Abstract This paper explores the benefits that would be achieved if gasoline marketers produced and offered a higher-octane gasoline to the U.S. consumer market as the standard grade. By raising octane, engine knock constraints are reduced, so that new spark-ignition engines can be designed with higher compression ratios and boost levels. Consequently, engine and vehicle efficiencies are improved thus reducing fuel consumption and greenhouse gas (GHG) emissions for the light-duty vehicle (LDV) fleet over time. The main objective of this paper is to quantify the reduction in fuel consumption and GHG emissions that would result for a given increase in octane number if new vehicles designed to use this higher-octane gasoline are deployed. GT-Power simulations and a literature review are used to determine the relative brake efficiency gain that is possible as compression ratio is increased. Engine-in-vehicle drive-cycle simulations are then performed in Autonomie to determine an effective, on-the-road vehicle efficiency gain.
Technical Paper
2014-04-01
Robert Golimbioschi, Giampiero Mastinu, Luca Cordioli, Massimiliano Gobbi, Davide Tagliabue, Giorgio Previati, Francesco Braga
Abstract A new electric powertrain and axle for light/medium trucks is presented. The indoor testing and the simulation of the dynamic behavior are performed. The powertrain and axle has been produced by Streparava and tested at the Laboratory for the Safety of Transport of the Politecnico di Milano. The tests were aimed at defining the multi-physics perfomance of the powertrain and axle (efficiency, acceleration and braking, temperature and NVH). The whole system for indoor tests was composed by the powertrain and axle (electric motor, driveline, suspensions, wheels) and by the test rig (drums, driveline and electric motor). The (driving) axle was positioned on a couple of drums, and the drums provided the proper torques to the wheels to reproduce acceleration and braking. Additionally a cleat fixed on one drum excited the vibration of the suspensions and allowed assessing NVH performance. The simulations were based on a special co-simulation between 1D-AMESIM and VIRTUAL.LAB. The contact between the wheels and the drums of the test rig were simulated by means of VIRTUAL.LAB.
Technical Paper
2014-04-01
Rounak Mehta, Preet Shah, Harsh Gupta, Prathamesh Bhat, Vaibhav Gandhi, Kimaya Kale, Madan Taldevkar, Akash Singh, Chinmay Ghoroi, Atul Bhargav, Amey Karnik
Abstract Three wheeler taxis, commonly known as auto rickshaw are a popular means of transport in developing countries. However, low efficiencies and poor maintenance are common (especially in India). This results in high fossil fuel consumption, and very high urban air pollution due to these vehicles. Electrification of auto-rickshaw, therefore, is a potential solution to reduce dependence on fossil fuels, and reduce environmental pollution. However, this conversion is not straightforward. In this work, we investigate some of the challenges of converting an existing combustion engine powered auto-rickshaw to an electric auto rickshaw (electric vehicle (EV)). The cost of conversion to EV and sufficient charge storage capacity for driving range are important factors in the viability of such a conversion. The solution developed here is a design for low total ownership cost for short-range transport. The factors that affect the total cost of ownership are local availability of components, performance efficiency, actual cost of conversion, and skills available with local technicians.
Technical Paper
2014-04-01
Youcai Liang, Gequn Shu, Hua Tian, Haiqiao Wei, Xingyu Liang, Mingru Zhao
Abstract Cogeneration system has become a valuable alternative approach for cascade waste heat recovery (WHR). In this paper, a novel electricity-cooling cogeneration system (ECCS) based on organic Rankine cycle-absorption refrigeration cycle (ORC-ARC) combined system is proposed to recover the waste heat of marine engine. ORC was adopted in the higher temperature cycle, in which alternatives D4, MDM and MM were selected as the working fluids. An ARC was adopted in the lower temperature cycle to recover the heat of the working fluid at the regenerator outlet in ORC. It aims to satisfy refrigeration requirement aboard ship, in which a binary solution of ammonia-water is used as the working pairs. Electricity output, cooling capacity, total exergy output, primary energy ratio (PER) and exergy efficiency are chosen as the objective functions. The results show that the additional cooling capacity is up to 10.9 MW, and such an ECCS has improved the exergy efficiency by 51% compared to the basic ORC.
Technical Paper
2014-04-01
Adam Fogarty, Kevin Oswald
In order to continue the effort of converting traditional internal combustion engine (ICE)-based vehicles into hybrid-electric vehicles (HEV), it is important to consider a variety of design architectures in which hybrid-electric operation is achieved. Such architectures include power split, parallel, and series. Of the previously stated architectures, the Purdue EcoMakers of the EcoCar 2 international Advanced Vehicle Technology Competition (AVTC) have chosen a parallel-through-the-road architecture for their 2013 Chevrolet Malibu provided by General Motors. From this, the Purdue EcoMaker vehicle design will be used as a case study for the design challenges and optimization strategies that are experienced when choosing this specific architecture for a light-duty passenger vehicle. This paper will focus on the design procedure and structural analysis of the custom rear suspension cradle created by the Purdue EcoMakers. Additionally, this paper will consider the benefits and practicality of using the structure of the custom suspension cradle as a design format for future suspension cradles to be used in light-duty passenger vehicles.
Technical Paper
2014-04-01
Mengjia Cao, Idan Kovent, Jerry Ku
Abstract Hybrid electric vehicle (HEV) is one of the most highly pursued technologies for improving energy efficiency while reducing harmful emissions. Thermal modeling and control play an ever increasing role with HEV design and development for achieving the objective of improving efficiency, and as a result of additional thermal loading from electric powertrain components such as electric motor, motor controller and battery pack. Furthermore, the inherent dual powertrains require the design and analysis of not only the optimal operating temperatures but also control and energy management strategies to optimize the dynamic interactions among various components. This paper presents a complete development process and simulation results for an efficient modeling approach with integrated control strategy for the thermal management of plug-in HEV in parallel-through-the road (PTTR) architecture using a flexible-fuel engine running E85 and a battery pack as the energy storage system (ESS). While the main motivation for the work is to deliver a design for the Department of Energy's EcoCAR2 Plugging in to the Future Competition, yet the framework and methodologies should be useful for any typical hybrid powertrain thermal and control development.
Technical Paper
2014-04-01
John P. Utley, David K. Irick
Abstract For the EcoCAR 2 collegiate engineering competition, The University of Tennessee is modifying a 2013 Chevrolet Malibu Eco from a mild hybrid into a series-parallel plug-in hybrid electric vehicle. For this design, the team is exchanging the engine for one that is E85 compatible, slightly separating the engine and transmission, and coupling an electric generator to the engine. In the rear of the vehicle, a modified all-wheel drive subframe will be implemented. This subframe will house a traction motor and a single gear electric drive transmission. A custom fuel tank and fuel system will be constructed for the vehicle, in order to use E85 fuel. Furthermore, an energy storage system will be placed in the rear of the vehicle, in the trunk and spare tire space. Modifications for the packaging must be made and analysis must be performed to validate the structural integrity of all modifications. Tennessee's engineering team is made up of five specific groups: mechanical, thermal, electrical, controls, and center stack teams.
Technical Paper
2014-04-01
Harveer Singh Pali, Naveen Kumar, Chinmaya Mishra
Abstract Biodiesel from non-edible vegetable oils is of paramount significance in India due to insufficient edible oil production. The present work deals with relatively underutilized non-edible oil “Schleichera oleosa” or “Kusum”. The Kusum biodiesel (KB) was produced using a two stage esterification cum transesterification process as the free fatty acid content of the oil was high. Important physico-chemical properties were evaluated and they were found to conform with corresponding ASTM/EN standards. Various test fuels were prepared for the engine trial by blending 10%, 20%, 30% and 40% of KB in diesel by volume and were named as KB10, KB20, KB30 and KB40 respectively. The results showed that full load brake thermal efficiency was dropped by 3.8% to 17% with increase in KB composition in the test fuel. Diesel (D100) showed the maximum full load brake specific energy consumption followed by KB10, KB20, KB30 and KB40. Hydrocarbons and Carbon monoxide emissions along with smoke opacity at full load were reduced by 7-42 %.
Technical Paper
2014-04-01
Li Sun, Mohamed Awadallah, Lianhua Chi, Nong Zhang
Abstract This paper presents a smart electric scooter system consisting of a microprocessor based vehicle controller (integrating an embedded regenerative braking controller), a 300W Permanent Magnet (PM) DC motor, two low-power DC-DC converters to form a higher power DC-DC converter pack, a motor controller, a supercapacitor bank and a capacitor cell balancing sub-system. During acceleration or forward motoring mode, the vehicle controller sets the DC motor into motoring mode to further utilizing motor controller regulate wheel speed and acceleration torque, whereas during deceleration or forward braking mode, sets the DC motor into braking mode and further utilizing regenerative braking controller regulate wheel speed and braking torque, as well as functions as a constant current (whose reference value is adjustable via a potentiometer) generator to charge the supercapacitor bank in a controllable fashion, hence not only successfully replacing frictional braking to certain degree, but also increasing the total energy efficiency dramatically owing to the low internal resistance and larger capacitance of the supercapacitor compared with other conventional regenerative braking systems via batteries.
Technical Paper
2014-04-01
Brian Sisk, Zhenli Zhang
Design of batteries for automotive applications requires a careful balance between vehicle requirements - as driven by automakers - and cost. Typically, for batteries, the goal is to meet the most stringent requirement at a competitive cost. The real challenge in doing so is understanding how the battery-level requirements vary with changes in the vehicle, powertrain, and drive cycle. In this work, we consider the relationship between vehicle-level and battery-level requirements of microhybrid vehicles and their linkage with battery design. These vehicle platforms demand high-power pulses for impractical durations - over 60 seconds on some drive cycles. We demonstrate a method for optimizing the battery design for fuel economy against any specific drive cycle, whether regulatory, consumer, or otherwise. This method allows for a high degree of customization against manufacturer or consumer value. Electrochemical modeling and vehicle modeling, coupled with experimental validation, is used to investigate the effects of key battery design parameters - such as particle size and coating thickness - on the energy and power capability of lithium ion batteries.
Technical Paper
2014-04-01
Ehsan Samadani, Leo Gimenez, William Scott, Siamak Farhad, Michael Fowler, Roydon Fraser
Abstract In electrified vehicle applications, the heat generated of lithium-ion (Li-ion) cells may significantly affect the vehicle range and state of health (SOH) of the pack. Therefore, a major design task is creation of a battery thermal management system with suitable control and cooling strategies. To this end, the thermal behavior of Li-ion cells at various temperatures and operating conditions should be quantified. In this paper, two different commercial pouch cells for plug-in hybrid electric vehicles (PHEVs) are studied through comprehensive thermal performance tests. This study employs a fractional factorial design of experiments to reduce the number of tests required to characterize the behavior of fresh cells while minimizing the effects of ageing. At each test point, the effects of ambient temperature and charge/discharge rate on several types of cell efficiencies and surface heat generation is evaluated. A statistical thermal ramp rate model is suggested which enables fast and accurate determination of cell surface temperature and heat generation where the vehicle is started from cold or warm environments at a range of constant currents over the entire state of charge (SOC) range.
Technical Paper
2014-04-01
Ehsan Samadani, Siamak Farhad, Satyam Panchal, Roydon Fraser, Michael Fowler
Abstract In this paper, initial results of Li-ion battery performance characterization through field tests are presented. A fully electrified Ford Escape that is equipped by three Li-ion battery packs (LiFeMnPO4) including an overall 20 modules in series is employed. The vehicle is in daily operation and data of driving including the powertrain and drive cycles as well as the charging data are being transferred through CAN bus to a data logger installed in the vehicle. A model of the vehicle is developed in the Powertrain System Analysis Toolkit (PSAT) software based on the available technical specification of the vehicle components. In this model, a simple resistive element in series with a voltage source represents the battery. Battery open circuit voltage (OCV) and internal resistance in charge and discharge mode are estimated as a function of the state of charge (SOC) from the collected test data. It is shown that although the OCV should be measured under no-load condition, still it can be estimated with an acceptable accuracy (∼5%) from the driving data.
Technical Paper
2014-04-01
Adam Ing, Ramin Masoudi, John McPhee, Thanh-Son Dao
Abstract Due to rising fuel prices and environmental concerns, Electric Vehicles (EVs) and Hybrid Electric Vehicles (HEVs) have been gaining market share as fuel-efficient, environmentally friendly alternatives. Lithium-ion batteries are commonly used in EV and HEV applications because of their high power and energy densities. During controls development of HEVs and EVs, hardware-in-the-loop simulations involving real-time battery models are commonly used to simulate a battery response in place of a real battery. One physics-based model which solves in real-time is the reduced-order battery model developed by Dao et al. [1], which is based on the isothermal model by Newman [2] incorporating concentrated solution theory and porous electrode theory [3]. The battery models must be accurate for effective control; however, if the battery parameters are unknown or change due to degradation, a method for estimating the battery parameters to update the model is required. A set of manufacturer recommended battery parameters were evaluated using a numerical sensitivity analysis to evaluate their identifiability.
Technical Paper
2014-04-01
Dragan Simic, Dominik Dvorak, Hannes Lacher, Helmut Kuehnelt, Elena Paffumi, Michele De Gennaro
Abstract This contribution deals with the modeling and validation of multi-physical battery-models, by using the programming language Modelica. The article presents a battery model which can be used to simulate the electric, thermal and aging behavior of a lithium-ion traction battery of an EV in different load conditions. The model is calibrated with experimental data of an electric vehicle tested on a chassis dynamometer. The calibration parameters, that are the open circuit voltage, the serial resistance and the resistance and capacitance of two serially connected RC-circuits, are used to configure the electric equivalent circuit model of the battery. The calibration process is based on a best-fit of the measured data from one test, while the validation is made by comparing measured and simulated battery voltages of a different battery load cycle. The comparison between simulations and experiments shows that this model is capable to accurately reproduce the real-world behavior of the battery, providing the scientific community with a novel approach for design and optimization purposes.
Technical Paper
2014-04-01
Rashad Mustafa, Mirko Schulze, Peter Eilts, Ferit Küçükay
Abstract Hybrid electric vehicles (HEV's) are facing increasing challenges in optimizing the energy flow through a vehicle system, in order to improve both fuel economy and vehicle emissions. Energy management of HEV's is a difficult task due to the complexity of the total system in terms of electrical, mechanical and thermal behavior. In this paper, an advanced control strategy for a parallel hybrid vehicle is developed. Four main steps are presented, particularly to achieve a reduction in fuel consumption. The first step is the development of a highly complex HEV model, including dynamic and thermal behavior. Second, a heuristical control strategy is developed to determine the HEV modes and third, a State of Charge (SoC) leveling is developed with the interaction of a fuzzy logic controller. It is proposed to calculate the load point shifting of the Internal Combustion Engine (ICE) and the desired battery SoC. Fourth, novel multi-objective optimization techniques, such as a genetic algorithm, are used for the optimization of the fuzzy logic controller and the heuristical control strategy.
Technical Paper
2014-04-01
David Ord, Eli White, P. Christopher Manning, Abhijit Khare, Lucas Shoults, Douglas Nelson
Abstract The Hybrid Electric Vehicle Team (HEVT) of Virginia Tech is excited about the opportunity to apply for participation in the next Advanced Vehicle Technology Competition. EcoCAR 3 is a new four year competition sponsored by the Department of Energy and General Motors with the intention of promoting sustainable energy in the automotive sector. The goal of the competition is to guide students from universities in North America to create new and innovative technologies to reduce the environmental impact of modern day transportation. EcoCAR 3, like its predecessors, will give students hands-on experience in designing and implementing advanced technologies in a setting similar to that of current production vehicles. The primary goals of the competition are to improve upon a conventional internal combustion engine production vehicle by designing and constructing a powertrain that accomplishes the following: Reduce Energy Consumption Reduce Well-to-Wheel (WTW) GHG Emissions Reduce Criteria Tailpipe Emissions Maintain Consumer Acceptability in the area of Performance, Utility, and Safety Meet Energy and Environmental Goals, while considering Cost and Innovation This paper presents results from several modeling problems and conceptual vehicle designs.
Technical Paper
2014-04-01
Brian Harries, Townsend Hyatt, Kenneth Leslie, Brandon Smith, Marc Compere
Abstract This paper describes the interdisciplinary architecture selection study conducted by Embry-Riddle Aeronautical University (ERAU) to determine the Plug-in Hybrid Electric Vehicle (PHEV) architecture for its entry into EcoCAR2: Plugging In To The Future. This study includes a fuel, component, and architecture comparison to determine the most viable strategy to convert the competition vehicle, a 2013 Chevrolet Malibu, into a strong PHEV. Performance, energy, emissions, and consumer acceptability goals were established and summarized in the Vehicle Technical Specifications (VTS). Drive cycle simulations were used to create vehicle and component requirements for achieving the VTS targets. Three candidate architectures were then evaluated and compared for energy consumption, well to wheel (WTW) emissions, WTW petroleum energy usage, performance, packaging, and consumer acceptability. The architectures compared were a front wheel drive Series PHEV, a series-parallel through the road PHEV, and pre-transmission PHEV.
Technical Paper
2014-04-01
Trevor Crain, Joshua Wilke, Brendan Boyer, Trevor Fayer, Brian Fabien, Per Reinhall
Abstract The University of Washington Advanced Vehicle Works team has spent the last two years designing and integrating a Parallel Through The Road (PTTR) PHEV drive system into a stock Chevy Malibu as part of the EcoCAR 2 Advanced Vehicle Technology Competition. This paper presents the integration efforts performed throughout year 2 in an effort to produce a 65% “buyoff ready” prototype vehicle. EcoCAR2 challenges 16 universities across North America to reduce the environmental impact of a 2013 Chevrolet Malibu without compromising consumer acceptability. The architecture chosen by the team to address these goals is a PTTR PHEV which provides all-electric operation to displace petroleum usage, four wheel drive mode to improve utility performance for consumers, and an efficient charge-sustaining mode using 20% biodiesel (B20). The PTTR architecture is the lowest cost architecture to provide all of these benefits, and it does so without compromising the safety or performance of the platform.
Technical Paper
2014-04-01
Domenic Leo Barsotti, Sandra Boetcher
Abstract The present study discusses the benefits of using a phase change material (PCM) based cold plate for more efficient energy storage system (ESS) cooling in Plug-In Hybrid Electric Vehicles (PHEV). This paper numerically demonstrates the benefits that a PCM cold plate has over a more conventional aluminum cold plate design. These benefits include six times more passive cooling capacity and a 66% mass reduction. Further investigations into improving the system were conducted in an effort to maximize passive cooling.
Technical Paper
2014-04-01
Kevin L. Snyder, Jerry Ku
Abstract The Wayne State University (WSU) EcoCAR2 student team is investigating powertrain optimizations as a part of their participation in the EcoCAR2 design competition for the conversion of a 2013 Chevrolet Malibu into a plug-in hybrid. EcoCAR2 is the current three-year Department of Energy (DoE) Advanced Vehicle Technical Competition (AVTC) for 15 select university student teams competing on designing, building, and then optimizing their Plug-In Hybrid conversions of GM donated vehicles. WSU's powertrain design provides for approximately 56-64 km (35-40 miles) of electric driving before the Internal Combustion Engine (ICE) powertrain is needed. When the ICE is started, the ICE traditionally goes through a cold start with the engine, transmission, and final drive all at ambient temperature. The ICE powertrain components are most efficient when warmed up to their normal operating temperature, typically around 90-100 °C. There are now some conventional vehicles currently available that employ active warm-up to recover waste heat from hot engine coolant to more quickly heat up the transmission fluid for reduced parasitic losses to improve fuel economy by approximately 2%. [1] [2] The WSU student team is investigating the improvements to fuel consumption (FC) of the ICE powertrain operation in the team's plug-in hybrid through pre-heating the ICE powertrain components before the engine is started.
Technical Paper
2014-04-01
Amanda Hyde, Shawn Midlam-Mohler, Giorgio Rizzoni
This paper describes the development and experimental validation of a Plug-in Hybrid Electric Vehicle (PHEV) dynamic simulator that enables development, testing, and calibration of a traction control strategy. EcoCAR 2 is a three-year competition between fifteen North American universities, sponsored by the Department of Energy and General Motors that challenges students to redesign a Chevrolet Malibu to have increased fuel economy and decreased emissions while maintaining safety, performance, and consumer acceptability. The dynamic model is developed specifically for the Ohio State University EcoCAR 2 Team vehicle with a series-parallel PHEV architecture. This architecture features, in the front of the vehicle, an ICE separated from an automated manual transmission with a clutch as well as an electric machine coupled via a belt directly to the input of the transmission. The rear powertrain features another electric machine coupled to a fixed ratio gearbox connected to the wheels. The model accounts for rotational dynamics and inertias of the torque generating components, gearboxes, and wheels.
Technical Paper
2014-04-01
Trevor Crain, Trevor Fayer, Brian Fabien, Per Reinhall
Abstract This paper details the development process and model architecture used in the University of Washington's EcoCAR 2 hybrid supervisory controller. The EcoCAR 2 project challenges 15 universities across North America to create a hybrid vehicle that most effectively minimizes emissions and fuel consumption while still maintaining consumer acceptability. The supervisory controller for the University of Washington was designed to distribute torque to the various electric and combustion drive systems on a parallel though the road plug-in hybrid electric vehicle using Simulink and Stateflow. The graphical interface of Simulink offers some distinct advantages over text-based programming languages. However, there are also significant challenges posed by the software, particularly when several controls engineers are working in parallel on a large model with some type of version control. In order to address some of these challenges, it is necessary to structure the model so that different areas of the program are properly partitioned to avoid instances of conflicting changes from different developers.
Technical Paper
2014-04-01
Shawn Salisbury, Thomas Bradley, Jake Bucher, Benjamin Geller
Abstract Plug-in Hybrid Electric Vehicles (PHEV) offer the benefits of both home charging from grid electricity and extended range from fuels. Fuel cell PHEVs in a range-extending (FCEREV) configuration build upon the advantages of PHEV by producing zero emissions while driving. The Colorado State University Vehicle Innovation Team (CSU VIT) successfully designed, built, and demonstrated a FCEREV named ‘H2eV’ for Year Two of the 3-year EcoCAR 2 collegiate competition. The demonstrated FCEREV is based on the 2013 Chevrolet Malibu and features a 15 kW Polymer Electrolyte Membrane fuel cell system, an 18.9 kWh/177 kW Li-Ion battery, and a 145 kW motor for all-electric drive. Operational data was taken during driving on a closed course, following a cycle that approximates the Environmental Protection Agency's 5-cycle test procedure. This paper provides an overview of the CSU VIT's FCEREV and a detailed analysis of vehicle performance during its successful demonstration. Analysis of fuel cell system operation provides proof-of-concept for the CSU VIT's FCEREV and highlights the emissions and energy consumption advantages of the designed vehicle for future development.
Technical Paper
2014-04-01
Swanand S. Kulkarni, Nikita Gandhi, Naga Chaithanya, Srinivasan Govindarajan
Abstract In a Mild hybrid electric vehicle, a battery serves as a continuous source of energy but is inefficient in supplying peak power demands required during torque assists for short duration. Moreover, the random charging and discharging that result due to varying drive cycle of the vehicle affects the life of the battery. In this paper, an Ultra-capacitor based hybrid energy storage system (HESS) has been developed for mild hybrid vehicle which aims at utilizing the advantages of ultracapacitors by combining them with lead-acid batteries, to improve the overall performance of the battery, and to increase their useful life. Active current-sharing is achieved by interfacing ultracapacitor to the battery through a bi-directional boost dc-dc converter. Furthermore, an energy management system (EMS) is developed that controls the power flow between the two sources and the load and determines the amount of charging of ultracapacitor either from the battery or during regeneration depending on the predictions based on the drive-cycle and the remaining energy of the ultracapacitor.
Technical Paper
2014-04-01
Wang Jun, Qingnian Wang, Pengyu Wang, Biao Han
Abstract The traditional vehicle design methods of hybrid electric vehicles are based on the rule-based control strategy, which often adopt the trial and error methods and the model-based numerical optimization methods. But these methods require a large number of repeated tests and a longer-term development cycle. In this paper, approximately the global optimization algorithm was used in control parameters designing through rational design of the penalty weights of objective function. But the optimized parameters apply only to vehicles that operating in the special drive cycle to get better fuel economy. Therefore, a drive cycle recognition algorithm was proposed to identify types of drive cycles in real-time, then an off-line genetic algorithm was adopted to acquire the optimization of control parameters under the various drive cycles, through drive cycle recognition results to choose the best control parameters. The simulation results demonstrate that adaptive energy strategy can improves the fuel-economy of hybrid electric vehicle and guarantees the vehicle power performance, driving performance.
Viewing 1 to 30 of 17597