Latest ArticlesIn order to improve the safety performance of automobiles and provide effective data support for the evaluation of automobile safety performance, the relevant requirements of the national standard GB 39732—2020 “Vehicle Event Data Recording System” for the data recorded by EDR are deeply analyzed, and the compliance judgment of EDR data of different manufacturers and models under various working conditions is carried out. The results show that the data that must be recorded according to the standard GB 39732 for all vehicle models is generally complete, but there are still imperfect data records under special driving conditions. Finally, some suggestions are put forward for the data that should be included in the recording scope of new energy vehicles when accidents occur.
Statistical Energy Analysis (SEA) is one of the conventional tools for predicting vehicle high-frequency acoustic responses. This study proposes a new method that can provide customized optimization solutions to meet NVH targets based on the specific needs of different project teams during the initial project stages. This approach innovatively integrates dynamic optimization, Radial Basis Function(RBF), and Fuzzy Design Variables Genetic Algorithm(FDVGA) into the optimization process of Statistical Energy Analysis(SEA), and also takes vehicle sheet metal into account in the optimization of sound packages. In the implementation process, a correlation model is established through Python scripts to link material density with acoustic parameters, weight, and cost. By combining Optimus and VaOne software, an optimization design workflow is constructed and the optimization design process is successfully executed. Under various constraints related to acoustic performance, weight and cost, a globally optimal design is achieved. This technology has been effectively applied in the field of Battery Electric Vehicle(BEV).
For the vacancy of the redundant braking system selection method, according to the performance requirements of the braking system, a design and verification method for the relevant components of the redundant braking system including motor, piston pump and solenoid valve was proposed. In this method, the deceleration index is transformed into the brake fluid pressure index through the theoretical calculation of vehicle dynamics, and the brake fluid pressure index is transformed into the liquid volume index through the pressure-volume characteristics of the braking system, and the liquid volume index is transformed into the flow index based on the response time requirement, so as to determine whether the solenoid valve scheme meets the requirements. Based on the structure and working principle of the motor and piston pump, the AMESim simulation model of the redundant braking system was established, and the simulation results were analyzed to determine whether the motor and piston pump scheme met the requirements. According to the vehicle parameters and brake parameters of a certain vehicle, the scheme check of the redundant braking system is carried out by using this method, which could provide support for the scheme selection of the redundant braking system.
With the widespread popularity of new energy vehicle models, electrical compressor operation noise is one of the main sources of electric vehicle noise. In order to analyze the mechanism of noise generation and clarify the noise characteristics and main transmission paths, this paper focuses on the study of order noise in electric compressor noise, and summarize the identification and optimization control methods of electric compressor noise based on the sources-path-response analysis model combined with engineering development examples. The research results indicate that: compared to traditional methods such as suppressing the compressor’s vibration force level and optimizing the vibration isolation capability of the transmission path, adopting a speed avoidance control strategy for the electric compressor to control the first-order booming noise is more cost-effective; optimizing and controlling the vibration isolation capability of the mounting brackets for the compressor and cooling fan are key to reducing the perceived amplitude of beat frequency noise inside the vehicle; based on the principle of auditory masking, the acceptance threshold for electromagnetic noise of the electric compressor can be increased by reasonably amplifying the noise of the cooling fan.
In order to study the impact of structural parameters of eddy current displacement sensor based on Printed Circuit Board (PCB) design on performance, this paper utilizes Ansys simulation software to establish a model of the eddy current displacement sensor. It analyzes the influence of various parameters, including coil excitation frequency and the gap between the coil and the measured target, on the system’s equivalent impedance and induced voltage. Based on the optimized model, a sensor prototype is constructed, and an experimental platform is established. An error analysis is conducted to compare the simulation results with the measured results. The experimental results show that the error of the optimized system reaches ±1.5% in the full range, thereby verifying the accuracy and feasibility of the model. This study provides a theoretical foundation for the development and application of the eddy current displacement sensors.
A single frequency point of 2.625 GHz exceeded the limit when the controller of parking auxiliary system carried out radiatied emission test of components, which did not meet the requirements of Electromagnetic Compatibility(EMC) Specs. By checking and analyzing the near and far field of the whole test link and Printed Circuit Board(PCB), it is found that the source of the noise is the Ethernet clock signal on PCB, and the clock and corresponding chip are not applied in this parking auxiliary system. The clock signal is radiated through the unintentional antenna formed by the broken line on the PCB board, resulting in the radiatied emission exceeding the limit. The reason why the radiation emission exceeded limits, and the process of discovering is described in detail, combined with theory and practice. By updating relevant software, turn off the clock driver, the problem of exceeding the limit of radiation emissied is solved at a low cost.
In order to analyze the output characteristics of the fuel cell system, this paper reviews the modeling of the stack level of Proton Exchange Membrane Fuel Cell (PEMFC) based on a large number of references, sorts out the research status of modeling of the proton exchange membrane fuel cell stack and the system level, summarizes the modeling methods and modeling purposes, and expounds the limitations and development trends of system modeling, which has reference significance for optimizing the control strategy and output performance of PEMFC system and accelerating the engineering application process of PEMFC.
Nowadays, in order to expand the roof view to bring passengers closer to nature, more and more new energy vehicles are opting for canopy designs without sunshades. However, after removing traditional sunshades, new solutions must be sought to address issues such as heat insulation, glaring sunlight, and interior reflections from the roof glass during the summer months. This paper conducts an in-depth analysis of the technical advantages and shortcomings of sunshade-free canopy in terms of heat insulation and interior reflections during summer, from both theoretical analysis and experimental comparison perspectives, and proposes improvement strategies. The research results indicate that although the panoramic roof enhances the vehicle’s interior view and technological appeal, it still has shortcomings in terms of heat insulation and the problem of interior reflections caused by direct sunlight. The proposed improvement strategies can effectively mitigate these issues, and offers consumers more comfortable and intelligent driving experiences.
Battery management system is conducive to maintaining excellent performances and safety of the vehicle power batteries, which is able to conduct functions of state estimation, energy equalization, thermal management and fault diagnosis. However, the traditional vehicle-end facility cannot meet the demands on hash rate and communication for advanced BMS. This paper proposes a cloud battery management system based on CHAIN (Cyber Hierarchy And Interactional Network), which can realize vehicle-cloud cooperation through End-Edge-Cloud-Intelligence mode and solve the problems of hash rate in distributed computation framework. It has the ability to provide different service delivery modes, including Infrastructure as a Service (IaaS), Platform as a Service (PaaS), Software as a Service (SaaS) and Data as a Service (DaaS). At last, several technical challenges and issues are concluded and an outlook on the multi-scenario applications of CHAIN is presented.
In order to deeply study the automatic and intelligent method of smart electric power supply, this paper explores the application of wireless power transmission(WPT) in the field of driverless electric vehicles. This paper first introduces the charging principles of the 2 wireless charging modes, and then designs the corresponding charging systems respectively. Combined with the simulation, the comparison and analysis of the single receiving coil and the multi-receiving coil are carried out. It is concluded that the double receiving coil has a better power inhibition effect on the dynamic wireless charging of electric vehicles, and the appropriate coil size and spatial distribution are given. Then combined with the engineering application, this paper puts forward the active position detection strategy of electric vehicles and the collaborative wireless charging scheme combining static and dynamic charging modes. Finally, the practical application of radio energy transmission technology in the field of intelligent driverless electric vehicles is introduced.