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Abstract Advanced passenger vehicles are complex dynamic systems that are equipped with several actuators, possibly including differential braking, active steering, and semi-active or active suspensions. The simultaneous use of several actuators for integrated vehicle motion control has been a topic of great interest in literature. To facilitate this, a technique known as control allocation (CA) has been employed. CA is a technique that enables the coordination of various actuators of a system. One of the main challenges in the study of CA has been the representation of actuator dynamics in the optimal CA problem (OCAP). Using model predictive control allocation (MPCA), this problem has been addressed. Furthermore, the actual dynamics of actuators may vary over the lifespan of the system due to factors such as wear, lack of maintenance, etc. Therefore, it is further required to compensate for any mismatches between the actual actuator parameters and those used in the OCAP.

Abstract This article presents a workflow for aerodynamic optimization of vehicles that for the first time combines the adjoint method and the efficient global optimization (EGO) algorithm in order to take advantage of both the gradient-based and gradient-free methods for aerodynamic optimization problems. In the workflow, the adjoint method is first applied to locate the sensitive surface regions of the baseline vehicle with respect to the objective functions and define a proper design space with reasonable design variables. Then the EGO algorithm is applied to search for the optimal site in the design space based on the expected improvement (EI) function. Such workflow has been applied to minimize the aerodynamic drag for a mass-produced electric vehicle. With the help of STAR-CCM+ and its adjoint solver, sensitive surface regions with respect to the aerodynamic drag are first located on the vehicle.

Abstract One of the key problems of battery electric vehicles is the risk of severe range reduction in winter conditions. Technologies such as heat pump systems can help to mitigate such effects, but finding adequate heat sources for the heat pump sometimes can be a problem, too. In cold ambient conditions below −10°C and for a cold-soaked vehicle this can become a limiting factor. Storing waste heat or excess cold when it is generated and releasing it to the vehicle thermal management system later can reduce peak thermal requirements to more manageable average levels. In related architectures it is not always necessary to replace existing electric heaters or conventional air-conditioning systems. Sometimes it is more efficient to keep them and support them, instead. Accordingly, we show, how latent heat storage can be used to increase the efficiency of existing, well-established heating and cooling technologies without replacing them.

Abstract As the automotive industry moves toward electrification, battery costs and vehicle range are two large issues that will delay this movement. These issues can be partially resolved through the use of series-hybrid vehicles, which can replace a portion of the batteries with a small engine that serves to recharge the battery. Given the size, weight, and operational constraints of this engine, a 2-stroke engine makes sense. Indeed, 2-stroke engines are currently being used for a number of applications including consumer products, small ground vehicles, boats, and drones. The technology has significantly improved to allow for reduced emissions and increased efficiency, especially through the use of direct injection. This article discusses the state of technology for 2-stroke engines and its application in series-hybrid vehicles. In particular, the use of a 2-stroke engine as a range extender provides significant benefit in range and cost over fully electric vehicles.

Abstract Advances in hybrid vehicles and electric vehicles (EV) are creating a need for a new generation of lubricants and new lubricant performance tests. Copper corrosion is one prominent concern for hybrid vehicles and EVs and is routinely assessed using a coupon test. This is characterized as metal dissolution, a surface tarnish, or a corrosion layer where a corrosion product remains on the surface and is characterized by a qualitative visual rating. This deficiency does not provide insight into the nature of the corrosion deposit. In an electric drive unit, there are multiple sources of the electric potential present, which can significantly alter the formation of a corrosion deposit which is not assessed in the coupon tests. The formation of a conductive corrosion deposit can result in catastrophic failure of the electric drive unit, either through direct shorting of the motor winding or failure of the power electronics.

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 Electric Vehicle (EV) equipped with two-speed transmission has benefit in improving dynamic performance and saving battery consumption. However, during gear shift process, torque interruption and shift impact may lead to a bad shift quality. This work investigates gear shift process in an Automated Manual Transmission (AMT) configuration-based two-speed transmission. First of all, a typical gear shift process is analyzed. Parameters like motor speed, shift force, motor torque change rate, and speed difference between synchronizer and target engage gear are all included to find the relationships with shift duration. Then vehicle jerk is introduced as a criterion to evaluate shift impact. Besides, a comprehensive shift control strategy is developed. While keeping the output torque at wheels unchanged, the shift strategy also improved motor working efficiency after gear shift.

Abstract China is driving the transition away from internal combustion engine vehicles (ICEVs) to plug-in electric vehicles (PEVs, including plug-in hybrid electric vehicles (PHEVs) and battery electric vehicles (BEVs)) to address its pressing energy security and environmental pollution problems. The recent enactment of the dual-credit scheme mandate will compensate for the phase out of the subsidy program, while ostensibly shifting the burden of filling in the cost gap between PEVs and ICEVs from the government to the automakers (though in practice to car buyers).

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.

Abstract Wheel loaders are widely used in construction projects. In order to reduce pollution and energy consumption, major wheel loader manufacturers are developing electric powertrain technology. Our main research goal is to reduce the energy consumption of a pure electric loader. This study is intended to build a vehicle simulation model of a multiple drive motor electric loader. According to the common working conditions and empirical formulas of the loader, the simulation data of the electric loader are calculated. The torque distribution control strategy based on the optimal efficiency of the motor is designed for the multiple drive motor electric loader and is compared with the equal proportion distribution control and the axle load ratio distribution control through simulation analysis. The simulation results show that the proposed torque distribution control strategy based on motor optimal efficiency can reduce energy consumption by 7–12%.

Abstract Torque interruption and shift jerk are the two main problems in the gear-shifting process of electric-driven mechanical transmission (EMT). This article gives a general solution of the time-optimal coordination control to eliminate the impacts between the sleeve and the gear ring in the shortest time in analytic form. The designed coordination control is proposed to the gear-shifting process with the sleeve and the gear ring on the same shaft but can be extended to satisfy different gear-shifting processes. To obtain this method, the gear-shifting dynamic model is first built according to the two different motion sources, the drive motor and shift motor. The time-optimal dual synchronization control and position control for the drive motor and shift motor are then solved, respectively.

Abstract The world community is constantly and rapidly moving toward the search for alternative and ecologically clean energy sources, including for transport, and Russia’s war against Ukraine only intensified and accelerated such processes. This trend in transport is reflected in the spread of battery-powered electric vehicles (BEVs) with zero emission of harmful gases. Electric cars are experiencing a rapid increase in numbers, accompanied by the emergence of lesser-known risks. Among these hazards are the occurrence of fires in electric vehicles, primarily caused by component failures, notably the widely prevalent lithium-ion batteries. Fires of such cars have a different character compared to fires of vehicles powered by an internal combustion engine vehicle (ICEV). In this study, using the fire dynamics simulator developed by the National Institute of Standards and Technology, a BEV fire was simulated on the example of the Tesla Model S.

Abstract High technology expertise and strong advancement in electric vehicles and Lithium (Li)-ion battery devices and systems have increased the speed of development and application of new equipment. It is reported that Li-ion battery life reduces almost by 60 days per degree temperature rise in an operational temperature of 30°C to 40°C, which makes cooling a high priority. The current study focuses on cooling the battery system using Phase Change Material (PCM) placed as bands of different dimensions around the prismatic battery. Eight novel designs of varying dimensions were constructed for three-volume scenarios. The heat generations considered in this study are 6,855 W/m3, 12,978 W/m3, 19,100 W/m3, and 63,970 W/m3. The data obtained was trained using an artificial neural network (ANN), and an equation was attained to fit the data. The optimum placement of PCM with respect to the number of bands and dimensions was achieved through a Genetic Algorithm.

Abstract Batteries have profound importance in today’s world as they are useful in powering the future without fossil fuels because of their properties, such as high energy density and durability. Volumetric and packing efficiency is better for a prismatic cell when compared with a cylindrical cell, whereas heat will be higher for a prismatic cell. This makes them a hot topic of research and development (R&D), with researchers finding ever more ways to improve. In this work, an attempt is made to study the effect of various mini-channel configurations on prismatic cell thermal management including the effect of C-rate, coolant flow rate, and coolant inlet temperature on temperature gradient and maximum cell temperature using ANSYS-Fluent by using an equivalent circuit model (ECM) in multi-scale multidimensional (MSMD) add-on module.

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