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This paper details the development of the control algorithms to characterize the behavior of an electrohydraulic actuated dry clutch used in the powertrain of the Wayne State University EcoCAR 3 Pre-Transmission Parallel hybrid vehicle. The paper describes the methodology and processes behind the development of the clutch physical model and electronic control unit to support the calibration of the vehicle’s hybrid supervisory controller. The EcoCAR 3 competition challenges sixteen North American universities to re-engineer the 2016 Chevrolet Camaro to reduce its environmental impact without compromising its performance and consumer acceptability. The team is in final stages of Year Two competition, which focuses on the powertrain components integration into the selected hybrid architecture. The dry clutch used by the team to enable the coupling between the engine and the electric motor is a key component of the Pre-Transmission Parallel configuration.

The objective of the research into modeling and simulation was to provide an improvement to the Wayne State EcoCAR 2 team’s math-based modeling and simulation tools for hybrid electric vehicle powertrain analysis, with a goal of improving the simulation results to be less than 10% error to experimental data. The team used the modeling and simulation tools for evaluating different outcomes based on hybrid powertrain architecture changes (hardware), and controls code development and testing (software). The first step was model validation to experimental data, as the plant models had not yet been validated. This paper includes the results of the team’s work in the U.S. Department of Energy’s EcoCAR 2 Advanced vehicle Technical Competition for university student teams to create and test a plug-in hybrid electric vehicle for reducing petroleum oil consumption, pollutant emissions, and Green House Gas (GHG) emissions.

This study investigates using driver prediction to anticipate energy usage over a 160-meter look-ahead distance for a series, plug-in, hybrid-electric vehicle to improve conventional thermostatic powertrain control. Driver prediction algorithms utilize a hidden Markov model to predict route and a regression tree to predict speed over the route. Anticipated energy consumption is calculated by integrating force vectors over the look-ahead distance using the predicted incline slope and vehicle speed. Thermostatic powertrain control is improved by supplementing energy produced by the series generator with regenerative braking during events where anticipated energy consumption is negative, typically associated with declines or decelerations.

The Wayne State University (WSU) EcoCAR 2 Team designed the conversion of a GM donated 2013 Chevrolet Malibu to a Parallel-Through-The-Road (PTTR) Plug-In Hybrid vehicle within a 9 month timeframe. This fast prototyping project used the EcoCAR 2 Vehicle Development Process (EVDP). Various tradeoffs were made to meet all competition requirements and to make the vehicle as competitive as possible within budget, time and experience limitations. The chosen PTTR architecture, nicknamed by the team as “E2D2” (Ethanol-Electric Dual-Drivetrain), provides up to 35.7 electric only miles and a fuel economy of 60 miles per gallons gasoline equivalent (mpgge) or 3.96 liters gasoline equivalent (lge) per one hundred km. This is accomplished using an E85 engine-driven front traction system and a battery-electric-motors-driven rear traction system. The team developed the control system and designed the packaging and integration of all required components including the Energy Storage System (ESS).

Although many simulations and analyses of three-phase insulated gate bipolar transistor (IGBT) switching devices exist in the offline and post processing arenas, real-time simulation environments require varying levels of fidelity of real-time capable models, depending on the task at hand. This paper presents a comparison between existing basic real-time modeling techniques and more advanced techniques capable of simulating complex electrical characteristics in high fidelity, while retaining the capability of real-time simulation. Model development, simulation, and analysis of results was performed at Mississippi State University in an effort to better understand the effects of multiple brushless direct current (BLDC) IGBT inverters operating on the same high-voltage bus.

The Wayne State University (WSU) EcoCAR2 student team designed, modeled, Model-In-the-Loop (MIL) tested, Software-In-the-Loop (SIL) simulation tested, and Hardware-In-the-Loop (HIL) simulation tested the team's conversion design for taking a 2013 Chevrolet Malibu and converting it into a Parallel-Through-The-Road (PTTR) plug-in hybrid. The 2013 Malibu is a conventional Front Wheel Drive (FWD) vehicle and the team's conversion design keeps the conventional FWD and adds a Rear Wheel Drive (RWD) powertrain consisting of an electric motor, a single speed reduction gearbox and a differential to drive the rear wheels -where none of these previously existed on the rear wheels. The RWD addition creates the PTTR hybrid powertrain architecture of two driven axles where the mechanical torque path connection between the two powertrains is through the road, rather than a mechanical torque path through gears, chains, or shafts.

The University of Washington EcoCAR2 team (UWEC2) is currently in the process of building a Plug-in Hybrid Electric Vehicle (PHEV) for the EcoCAR2 Challenge. This competition challenges 15 universities across North America to reduce the environmental impact of a 2013 Chevrolet Malibu without compromising consumer acceptability. In order to be competitive in EcoCAR2, grid electricity is relied on heavily and the use of the Utility Factor method presented in SAE J2841 - Utility Factor Definitions must be used to compare emissions and consumption results with traditional vehicle results. Powertrain simulation in Autonomie was performed to explore many different hybrid architectures. The simulation results were normalized using the Utility Factor method to reach final architecture and component decisions.

The Wayne State University (WSU) EcoCAR2 student team is participating in a design competition for the conversion of a 2013 Chevrolet Malibu into a plug-in hybrid. The team created a repeatable on-road test drive route using local public roads near the university that would be of similar velocity ranges contained in the EcoCAR2 4-Cycle Drive Schedule - a weighted combination of four different EPA-based drive cycles (US06 split into city and highway portions, all of the HWFET, first 505 seconds portion of UDDS). The primary purpose of the team's local on-road route was to be suitable for testing the team's added hybrid components and control strategy for minimizing petroleum consumption and tail pipe emissions. Comparison analysis of velocities was performed between seven local routes and the EcoCAR2 4-Cycle Drive Schedule. Three of the seven local routes had acceptable equivalence for velocity (R₂ ≻ 0.80) and the team selected one of them to be the on-road test drive route.

A procedure for obtaining the optimum disk serration and blade root geometry is presented. The procedure uses the -finite element method, a suitable objective function and a standard mathematical programming technique as its basis. The objective functions investigated are the mean von Mises stress concentration factor, the coefficient of efficiency, and the hoop stress and radial stress concentration factors. The mathematical programming techniques considered are the Steepest Descent Technique, the Hill Algorithm and the Box Method. Results presented in this paper include the relative cost and the degree of success achieved by the design optimization procedure.

The Wayne State University student team reengineered a mid-sized sedan into a functional plug-in hybrid electric vehicle as participants in the EcoCAR 2 competition sponsored by the US Department of Energy and managed by Argonne National Laboratory. The competition goals included reducing petroleum usage, emissions, and energy consumption through implementing advanced vehicle technologies. During the competition, the team did plug-in charging of the 19 kWh high voltage traction battery, drove in pure electric mode (engine off) until the battery was depleted, then switched to hybrid mode and continued driving by using E85 from the fuel tank. The pure electric mode vehicle driving range was 48 km [30 miles] while pulling an emissions instrumented test trailer and projected to be 58 km [36 miles] without the test trailer load for the competition's city/highway blend drive cycle.

It is well known that thermal management is a key factor in design and performance analysis of Lithium-ion (Li-ion) battery, which is widely adopted for hybrid and electric vehicles. In this paper, an air cooled battery thermal management system design has been proposed and analyzed for mild hybrid vehicle application. Computational Fluid Dynamics (CFD) analysis was performed using CD-adapco's STAR-CCM+ solver and Battery Simulation Module (BMS) application to predict the temperature distribution within a module comprised of twelve 40Ah Superior Lithium Polymer Battery (SLPB) cells connected in series. The cells are cooled by air through aluminum cooling plate sandwiched in-between every pair of cells. The cooling plate has extended the cooling surface area exposed to cooling air flow. Cell level electrical and thermal simulation results were validated against experimental measurements.

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).

EcoCAR 2: Plugging in to the Future (EcoCAR) is North America's premier collegiate automotive engineering competition, challenging students with systems-level advanced powertrain design and integration. The three-year Advanced Vehicle Technology Competition (AVTC) series is organized by Argonne National Laboratory, headline sponsored by the U. S. Department of Energy (DOE) and General Motors (GM), and sponsored by more than 30 industry and government leaders. Fifteen university teams from across North America are challenged to reduce the environmental impact of a 2013 Chevrolet Malibu by redesigning the vehicle powertrain without compromising performance, safety, or consumer acceptability. During the three-year program, EcoCAR teams follow a real-world Vehicle Development Process (VDP) modeled after GM's own VDP. The EcoCAR 2 VDP serves as a roadmap for the engineering process of designing, building and refining advanced technology vehicles.

Connected and automated technologies poised to change the way vehicles operate are starting to enter the mainstream market. Methods to accurately evaluate these technologies, in particular for their impact on safety and energy, are complex due to the influence of static and environmental factors, such as road environment and traffic scenarios. Therefore, it is important to develop modeling and testing frameworks that can support the development of complex vehicle functionalities in a realistic environment. Microscopic traffic simulations have been increasingly used to assess the performance of connected and automated vehicle technologies in traffic networks. In this paper, we propose and apply an evaluation method based on a combination of microscopic traffic simulation (AIMSUN) and a chassis dynamometer-based vehicle-in-the-loop environment, developed at Argonne National Laboratory.

The Wayne State University EcoCAR2 team provided its members with Modeling and Simulation training course for the second summer of the competition. EcoCAR2 is a three-year Advanced Vehicle Technology Competition (AVTC) sponsored by General Motors and the Department of Energy. The course lasted three months and included 45 hours of formal lectures and class hands-on work and an estimated one hundred and fifty hours in home assignments that directly contributed to the team's deliverables. The course described here is unique. The design and class examples were extracted from an in-house complete vehicle simulation and control code to ensure hands-on, interactive training based on real-world problems. The course investigated the physics behind every major powertrain component of a hybrid electric vehicle and the different ways to model the components into a full vehicle simulation.

This paper details the Wayne State University development of the Hybrid Supervisory Controller strategies for the Year 3 of the EcoCAR 3 competition. Included in this paper are the processes for developing the strategies for the supervisory control system, which includes the torque distribution among the powertrain components, and the diagnostic strategies adopted to guarantee the safety critical functionalities of the vehicle. The EcoCAR 3 competition challenges sixteen North American universities to re-engineer the 2016 Chevrolet Camaro to reduce its environmental impact without compromising its performance and consumer acceptability. During the Year 3 of the competition the team has refined the control strategies designed in the previous years, to enable the powertrain full functionalities and achieve better energy consumption over pre-determined drive cycles.