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Abstract It is widely understood that the thermal state of a light-duty vehicle at the beginning of a trip influences the vehicle performance throughout the drive cycle. Cold starts, or initial states with component temperatures near ambient conditions, are strongly correlated with reduced vehicle performance and energy efficiency and increased emissions. Despite this understanding, there is little literature available that characterizes initial thermal states beyond empirical studies and simplified analyses of dwell times. We introduce a framework that considers vehicle activity patterns, including the previous drive event, duration of the previous dwell event, and relevant ambient conditions occurring during these events. Moreover, the framework allows for technologies to influence the prominence of cold starts and warm starts.

Abstract This article applies a new method for the evaluation and estimation of real-life energy consumption of two different thermal management systems based on driving behavior in the course of the day. Recent attempts to find energy-efficient thermal management systems for electric and plug-in hybrid electric vehicles have led to using secondary loop systems as an alternative approach for meeting dynamic heating and cooling demands and reducing refrigerant charge. However, the additional layer of thermal resistance, which influences the system’s transient behavior as well as passenger compartment comfort during cool-down or heat-up, makes it difficult to estimate the annual energy consumption. In this article, the overall energy consumption of a conventional and a secondary loop system is compared using a new method for describing actual customers’ driving behavior in the course of the day.

Abstract The high-frequency noise issue is one of the most significant noise, vibration, and harshness problems, particularly in battery electric vehicles (BEVs). The sound package treatment is one of the most important approaches toward solving this problem. Owing to the limitations imposed by manufacturing error, assembly error, and the operating conditions, there is often a big difference between the actual values and the design values of the sound package components. Therefore, the sound package parameters include greater uncertainties. In this article, an uncertainty analysis method for BEV interior noise was developed based on an interval model to investigate the effect of sound package uncertainty on the interior noise of a BEV. An interval perturbation method was formulated to compute the uncertainty of the BEV’s interior noise.

Abstract The proposed approach present the development of a computer tool that allows, in the first phase, the modeling of the electric vehicle power chain. This phase is based on a library developed under the Matlab-Simulink simulation environment. This library contains all the components of the power chain; it offers the selection of the desired configuration of each component. In the second phase, the tool solves the autonomy optimization problem. This problem is resolved by a program based on genetic algorithms. This program permits to optimize the configuration parameters maximizing the vehicle autonomy of the chosen chain. This tool is based on a graphical interface developed under the Matlab simulation environment.

Abstract Future SAE Level 4 and Level 5 autonomous vehicles (AV) will require novel applications of localization, perception, control, and artificial intelligence technology in order to offer innovative and disruptive solutions to current mobility problems. This article concentrates on low-speed autonomous shuttles that are transitioning from being tested in limited traffic, dedicated routes to being deployed as SAE Level 4 automated driving vehicles in urban environments like college campuses and outdoor shopping centers within smart cities. The Ohio State University has designated a small segment in an underserved area of the campus as an initial AV pilot test route for the deployment of low-speed autonomous shuttles. This article presents initial results of ongoing work on developing solutions to the localization and perception challenges of this planned pilot deployment.

Abstract In the case of electric vehicles, due to the charging current limitation of lithium battery at low temperatures (below -20°C), it has been proposed to heat the battery pack up to a suitable temperature range before charging through a liquid-heating plate with PTC. However, at a low state of charge (SOC), there is a question which one could take the place of battery pack to supply power for PTC when heating. So that off-board charger (OFC) has been considered to supply power for PTC in this paper. In order to control the current charging into the battery pack as less as possible at low temperatures, three control schemes of battery management system (BMS) are proposed and compared. Scheme 1: BMS controls the value of charging current request close to the working current of PTC. Scheme 2: BMS controls the value of charging voltage request to reach a state of relative balance. Scheme 3: BMS disconnects the pack from the charger and keeps the connection between PTC and charger.

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Abstract Currently, the governments are encouraging automotive vehicle manufacturers to produce electric vehicles (EVs) as these vehicles have a zero-emission footprint. Generally, the EVs are expected to be quieter compared to internal combustion engine (ICE) vehicles. But the absence of engine noise in EVs brings more challenges for noise, vibration, and harshness (NVH) as the other noise sources become more audible. Most of these noise sources are tonal in nature and, hence, cause discomfort to the passengers. The present work is related to the noise refinement in a pure EV. The dominant noise sources observed in this vehicle are the electric powertrain, cooling fan, and air compressor. The powertrain consists of a traction motor and a gearbox (GB) with a planetary gear system. The root cause identification of electric powertrain noise has been investigated with masking trials and with the acoustic camera.

Abstract Due to the advantages of hybrid vehicles in comparison with pure electric vehicles, Hybrid Electric Vehicle (HEV)/Plug-in HEV (PHEV) no undoubtedly becomes the reasonable and practical solution in the development of vehicle electrification at the moment. Meanwhile, Dedicated Hybrid Transmission (DHT), as the especially designed hybrid transmission for HEV/PHEV, represents the development direction of hybrid vehicles. But in the market, the well-known DHT concepts are all protected by patents by large Original Equipment Manufacturers (OEMs). How to break the patents and more importantly develop the innovative DHT concepts in the next generation is of vital importance in the development of HEV/PHEV. In this article, firstly, the features and comparisons of different well-known DHT concepts are discussed and analyzed. The mechanical and electrical complexity are introduced to essentially analyze the advantage and disadvantage of different kinds of DHT concepts.

Abstract Objectified analysis and evaluation tools offer cost- as well as time-saving potentials regarding the calibration process of vehicle control units. To reduce the time required for the calibration effort, standardized processes including the frontloading of development tasks enable swift calibration procedures and can be used to develop a basis for the comparison of different vehicles and also the calibration quality. In this environment, objectified evaluation methods are also being developed for the investigation of the drivability of electric vehicles. This article presents a methodology for assessing the longitudinal drive behavior of battery electric vehicles during deceleration maneuvers. The aim is to objectively evaluate the vehicle deceleration by means of reproducible driving maneuvers. In addition to further measurement signals, the longitudinal acceleration signal serves as the main evaluation basis.

Abstract This work puts presents an all-inclusive state of the art bibliographical review of all categories of electrified transportation (xEVs) standards, issued by the most important standardization organizations. Firstly, the current status for the standards by major organizations is presented followed by the graphical representation of the number of standards issued. The review then takes into consideration the interpretation of the xEVs standards developed by all the major standardization organizations across the globe. The standards are differentiated categorically to deliver a coherent view of the current status followed by the explanation of the core of these standards. The ISO, IEC, SAE, IEEE, UL, ESO, NTCAS, JARI, JIS and ARAI electrified transportation vehicles xEV Standards from USA, Europe, Japan, China and India were evaluated. A total approximated of 283 standards in the area have been issued.

Abstract In the following, a multiphysics simulation approach for the calculation of the noise, vibration, and harshness (NVH) behavior of a three-phase permanent magnet synchronous machine is presented. Based on a defined operating point, the electromagnetic force densities in the air gap between the rotor and stator are determined on the basis of the flowing currents using the finite element method (FEM). In addition to the electromagnetic force densities, the structural modes with natural frequency and natural mode shapes are also determined by modal analysis. The electromagnetic forces and structural modes can then be reduced to the most important contributions in the modal space to significantly reduce the computation time. Using a frequency-dependent damping model, a full motor run-up is simulated and the resulting velocities at the surface of the machine are evaluated. The simulation results are then compared with a measurement and validated.

Abstract A classical antiskid brake system (ABS) is typically used to control the brake fluid pressure by creating repeated cycles of decreasing and increasing brake force to avoid wheel locking, causing the fluctuation of the brake hydraulic pressure and resulting in vibration during wheel rotation. This article proposes a new approach of skid control for ABS by controlling the disk pad position. This new approach involves using a modest control method to determine the optimal skid that allows the wheel to exert maximum friction force for decelerating the vehicle by shifting the brake pad position instead of modulating the brake fluid pressure. This pad position control (PPC) method works in a continuous manner. Therefore, no rapid changes are required in the brake pressure and wheel rotation speed. To identify the PPC braking performance, braking test simulations and experiments have been carried out.

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Abstract Distributed drive electric vehicles can apply the four-wheel differential drive to change the vehicle handling performance, which can make the connected and automated vehicles (CAV) more controllable. This article proposes a hierarchical scheme of the torque-vectoring controller (TVC), whose key parameters affecting the control objective are optimized from the human-vehicle closed-loop simulation test. First, the radial basis function (RBF)-based adaptive second-order sliding mode control (RASOSMC) for additional yaw moment generation is designed in the upper layer of the controller. The lower layer is the torque distribution strategy that takes into consideration the minimization of the tire load and the control error of the additional yaw moment and yaw rate. Afterward, the longitudinal and lateral driver model with the adaptive correction of preview time is established.