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Published by AUTO FAN Magazine Co. Ltd.

Table of Content

    25 September 2024, Volume 46 Issue 9 Previous Issue    Next Issue
    Risk Prediction of Heterogeneous Traffic Participants Based on Spatio-Temporal Graph Neural Networks
    Xianghao Meng,Ling Niu,Junqiang Xi,Danni Chen,Chao Lü
    2024, 46 (9):  1537-1545.  doi: 10.19562/j.chinasae.qcgc.2024.09.001
    Abstract ( 371 )   HTML ( 21 )   PDF (4301KB) ( 400 )   Save

    Effectively predicting the future risk indicators of multiple traffic participants under the driver's field of vision is the key to providing risk warnings to human drivers and avoiding potential collision risk. Most existing research on risk only considers the pairwise interaction between a single individual and the vehicle in the scene, and conducts research from the perspective of evaluation rather than prediction, while ignoring the different interaction between heterogeneous traffic participants and future risk status. This paper proposes a heterogeneous multi-objective risk prediction method Risk-STGCN based on spatiotemporal graph convolutional neural network, using graph convolution and temporal convolution to learn single-frame scene graph information and timing information respectively, combined with multi-layer timing prediction network to predict the multi-objective risk indicator TTC. Training and verification are conducted on the open source data set BLVD and the real vehicle self-collected data set, which is then compared with commonly used sequence prediction models. The experimental results show that the average TTC error of the proposed model on different data sets is less than 0.95 s, with multiple experimental indicators better than other models mentioned in this paper. The proposed model has good robustness and improves the interpretability of risk prediction in complex traffic scenarios.

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    Research on Global Oriented Path Planning Fusion Algorithm for Intelligent Vehicles
    Shuo Zhang,Shiqi Kuang,Xuan Zhao,Yisong Chen,Qiang Yu,Man Yu
    2024, 46 (9):  1546-1555.  doi: 10.19562/j.chinasae.qcgc.2024.09.002
    Abstract ( 220 )   HTML ( 17 )   PDF (3774KB) ( 506 )   Save

    For the problems of path planning on curved roads, a path planning fusion algorithm based on global oriented artificial potential field method is proposed in this paper. Considering the curved road conditions, a grid map based on deformed grid is constructed. Considering the driving risk in the road environment, the heuristic function of A* algorithm is optimized based on the driving risk field theory. To improve the limitation and inherent defects of the traditional artificial potential field method, in view of the outline shapes of the subject vehicle, environment vehicles and obstacles, the artificial potential field method is improved as the local path planning method by introducing in the globally guided path. Taking the path planned by the improved A* algorithm as the global optimal guided path, the path planning fusion algorithm is designed based on the improved artificial potential field method. The simulation results show that the proposed fusion algorithm can generate effective and reasonable driving path, which is close to the real vehicle path extracted from the dataset. Moreover, the path planned in the environment with obstacles is safe and efficient, meeting the driving requirements of the vehicle.

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    Application of Scenario Complexity Evaluation in Trajectory Prediction and Automated Driving Decision-Making
    Daofei Li,Hao Pan
    2024, 46 (9):  1556-1563.  doi: 10.19562/j.chinasae.qcgc.2024.09.003
    Abstract ( 176 )   HTML ( 8 )   PDF (3227KB) ( 261 )   Save

    The evaluation of scenario complexity is crucial for improving adaptability and flexibility of autonomous vehicles in coping with complex environments and enhancing the applicability of the algorithms. A graph-based algorithm for evaluating scenario complexity is developed in this paper, which fully considers interactive topology and categorizes traffic scenarios into three complexity levels. The reasonability and effectiveness are validated in ramp merging scenarios. To demonstrate its scalability, the evaluation algorithm is applied in the development of the trajectory prediction and decision-making algorithms of automated driving. The proposed algorithms are then tested using natural driving datasets and vehicle-in-the-loop experiments. The results indicate that scenario complexity evaluation enables early estimation of prediction uncertainty, enhances the real-time and optimality of decision-making algorithms. In data replay tests, the complexity assessment module can reduce the failure rate and collision rate during lane merging by approximately 38% and 92%, respectively, indicating promising application prospects.

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    Trajectory Planning for Intelligent Vehicle in Dynamic Unstructured Environment Based on the Graph Search and Optimization Methods
    Xiujian Yang,Yongrui Bai
    2024, 46 (9):  1564-1575.  doi: 10.19562/j.chinasae.qcgc.2024.09.004
    Abstract ( 146 )   HTML ( 8 )   PDF (4724KB) ( 282 )   Save

    A trajectory planning method based on graph search and optimization is proposed for intelligent vehicle trajectory planning in dynamic unstructured environments. Firstly, the graph search method is employed to search for motion primitives for intelligent vehicles to obtain initial trajectories that conform to kinematic characteristics. Then, based on nonlinear model predictive control methods, the trajectory is optimized to obtain smoother and safer trajectories. In order to achieve rapid and secure expansion of primitives in dynamic unstructured environments, a method for primitive collision detection is proposed. This method uses obstacle expansion and grid discrete motion elements to perform static collision detection on irregular obstacles, and introduces in the concept of velocity obstacles to perform dynamic collision detection on dynamic obstacles in velocity space. The proposed algorithm is compared by simulations in ROS/Gazebo environment, and is evaluated by field tests. The results show that compared to the TEB algorithm, the proposed trajectory planning method improves the average obstacle avoidance success rate by 18% while meeting the real-time computing requirements, demonstrating higher safety obstacle avoidance ability and feasibility.

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    A Hybrid Control Strategy for Light Commercial Vehicle Path Tracking Considering Complex Disturbances
    Jie Hu,Zhiling Zhang,Jiefeng Zhong,Wenlong Zhao,Jiachen Zheng,Silong Zhou,Zijun Qu
    2024, 46 (9):  1576-1586.  doi: 10.19562/j.chinasae.qcgc.2024.09.005
    Abstract ( 129 )   HTML ( 5 )   PDF (4145KB) ( 201 )   Save

    Complex disturbances such as external interference, model uncertainty and parameter perturbation directly affect the accuracy and driving safety of intelligent vehicle path tracking control. Commercial vehicles are more susceptible to complex disturbances during driving because of their load characteristics. A hybrid path tracking control method is proposed in order to improve the accuracy and smoothness of commercial vehicle path tracking. Firstly, a robust sliding mode controller based on extended observer and an incremental LQR controller with stable changes are established. Particle swarm optimization algorithm is used to tune the parameters of the incremental LQR. Then, in order to improve robustness while weakening chattering, a fuzzy controller is used to adjust weight coefficient between them according to vehicle speed and lateral error. Finally, simulation analysis and vehicle experiments are conducted. The experimental data shows that SMC+LQR has good control performance to cope with complex external disturbances.

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    Research on Fast Stochastic Model Predictive Control-Based Eco-Driving Strategy for Connected Mixed Platoons
    Lijun Qian,Jian Chen,Feng Zhao,Xinyu Chen,Liang Xuan
    2024, 46 (9):  1587-1599.  doi: 10.19562/j.chinasae.qcgc.2024.09.006
    Abstract ( 126 )   HTML ( 6 )   PDF (3632KB) ( 184 )   Save

    To address the problem of speed trajectory deviation of connected vehicles (CVs) caused by human driver error, a real-time eco-driving strategy for connected mixed platoons considering human driver error is proposed in this paper. Firstly, real vehicle tests are conducted to collect human driver error data of different drivers to establish the human driver error model based on Markov chain so as to predict the human driver error for a period of time in the future. Then, with the optimization objective of minimizing the fuel consumption of the entire platoon, the platoon speed trajectory optimization problem is formulated as an optimal control problem. Fast stochastic model predictive control (FSMPC) is employed to calculate the optimal speed trajectories of the connected vehicle in the mixed platoon. Both the simulation and intelligent and connected micro-car test results indicate that, compared to the traditional eco-driving strategy based on fast model predictive control (FMPC), the proposed eco-driving strategy can effectively reduce the speed trajectory deviation and fuel consumption of the whole platoon as well as meet the real-time requirements.

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    Generation Method for Anthropomorphic Continuous Interactive Test Scenarios of Automated Driving
    Bing Zhu,Tianxin Fan,Jian Zhao,Peixing Zhang,Dongjian Song,Yue Xue,Wenbo Zhao
    2024, 46 (9):  1600-1607.  doi: 10.19562/j.chinasae.qcgc.2024.09.007
    Abstract ( 194 )   HTML ( 11 )   PDF (1562KB) ( 357 )   Save

    Scenario-based simulation test method is an important means of automated driving vehicle safety verification; however, current test scenarios generation methods are mostly for independent scenarios. How to simulate the human real driving process to generate continuous interactive test scenario with challenges has become a problem that needs to be solved urgently in automated driving test evaluation. In this paper, an automated driving anthropomorphic continuous interactive test scenarios generation method is proposed. Firstly, the architecture for anthropomorphic continuous interactive test scenarios generation is established, and the vehicle motion behavior analysis is conducted based on the HighD dataset. On this basis, the current behavior of tested automated driving vehicle based on the trajectory similarity feature is analyzed, and the prediction of the future trajectory through the state transfer matrix is realized. Then, the type of the future behaviors of the traffic vehicles based on the trajectory interaction rules are determined, and the specific trajectory is generated by Transform network. Finally, the key performance indicators such as danger and anthropomorphism of the generated test scenarios are evaluated in simulation test environment, which proves the effectiveness of the method proposed in this paper.

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    A LiDAR-Based Dynamic Driving Scene Multi-task Segmentation Network
    Hai Wang,Jianguo Li,Yingfeng Cai,Long Chen
    2024, 46 (9):  1608-1616.  doi: 10.19562/j.chinasae.qcgc.2024.09.008
    Abstract ( 123 )   HTML ( 5 )   PDF (4342KB) ( 223 )   Save

    In autonomous driving scene understanding task, accurate segmentation of drivable areas, dynamic and static objects is essential for subsequent local motion planning and motion control. However, the current general semantic segmentation method based on lidar point cloud cannot achieve real-time and robust prediction on vehicle-end edge computing devices, and cannot predict the motion state of objects at the current moment. In order to solve this problem, a multi-task segmentation network MultiSegNet for driving areas and dynamic and static objects is proposed in this paper. The network uses the depth map output by the lidar and the processed residual image as the representation of the encoded spatial features and motion features to input to the network for feature learning, so as to avoid directly processing disordered high-density point clouds. For the large difference in the number of target distributions in different directions of the depth map, a variable resolution grouping input strategy is proposed, which can reduce the amount of network computation and improve the segmentation accuracy of the network. In order to adapt to the size of the convolutional receptive field required for targets at different scales, a depth-value-guided hierarchical dilated convolution module is proposed. At the same time, in order to effectively correlate and fuse the spatial position and attitude information of objects in different time domains, a spatiotemporal motion feature enhancement network is proposed. The effectiveness of the proposed MultiSegNet is verified on the large-scale point cloud driving scene datasets SemanticKITTI and nuScenes. The results show that the segmentation IoU of driving area, static object and dynamic object reaches 98%, 97% and 70%, respectively, which is better than that of mainstream networks, with real-time inference realized on edge computing devices.

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    A Survey on Ride Comfort Evaluation of Autonomous Vehicles
    Guojuan Zhang,Hongyu Hu,Haomiao Li,Mingjian Wang,Fei Gao,Zhenhai Gao
    2024, 46 (9):  1617-1627.  doi: 10.19562/j.chinasae.qcgc.2024.09.009
    Abstract ( 414 )   HTML ( 42 )   PDF (1222KB) ( 1310 )   Save

    With the rapid development of automated driving technology, ride comfort has become a key factor affecting user acceptance and overall experience with automated vehicles. In this paper, a comprehensive review of the current state of research concerning the evaluation of riding comfort in automated vehicles is presented. Firstly, the concept of comfort is thoroughly articulated, followed by an analysis of key factors influencing ride comfort. Subsequently, the quantitative indicators and evaluation models pertinent to automated vehicles are classified and elaborated in detail. The quantitative indicators are classified into four categories: subjective indicators, indicators derived from vehicle parameters, indicators based on physiological signals, and indicators related to driver behaviour. The evaluation models encompass psychophysical models, biomechanical models, statistical models, and learning-based evaluation models. Finally, prospective trends in the research of comfort in automated vehicles is brought forward, thereby offering a technical framework for further studies on the system design and user experience in this domain.

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    Effect of Fuel Control Parameters of the Active Pre-chamber on the Gasoline Engine Lean Burn Characteristics
    Bingxin Xu,Xinke Miao,Jun Deng,Jinqiu Wang,Liguang Li
    2024, 46 (9):  1628-1632.  doi: 10.19562/j.chinasae.qcgc.2024.09.010
    Abstract ( 105 )   HTML ( 4 )   PDF (1740KB) ( 155 )   Save

    The pre-chamber ignition system can enhance the lean mixture combustion, which will then improve the thermal efficiency significantly. Based on a self-developed active pre-chamber and its fuel supply system, the effect of premixed gas injection pressure and fuel ratio on combustion characteristics at the lean boundary of an engine with a compression ratio of 16 is respectively investigated. The experimental results show that among the three kinds of premixed gas injection pressure of 0.19,0.14 and 0.09 MPa, the indicated mean effective pressure is the highest, and the ignition delay time and combustion duration are the lowest at the injection pressure of 0.09 MPa, with the most stable combustion. When the proportion of premixed gas fuel increases from 0.54% to 2.69% gradually, the engine's indicated mean effective pressure (IMEP) increases first, and then decreases, reaching its maximum at a ratio of 1.61% when the combustion is most stable and both the ignition delay period and combustion duration are the shortest. The active pre-chamber can realize the stable combustion with a λ of 1.8. Indicated thermal efficiency increases from 32.9% to 39.4%, a relatively increase of 19.8% compared with that of spark plug ignition.

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    Study on the Influence of Passive Pre-chamber Combustion Strategy on In-cylinder Combustion and Emission Characteristics of Gasoline Engines
    Lü Yang,Shangsi Feng,Jing Luo,Lan Li,Zhe Kang
    2024, 46 (9):  1633-1642.  doi: 10.19562/j.chinasae.qcgc.2024.09.011
    Abstract ( 86 )   HTML ( 2 )   PDF (4180KB) ( 102 )   Save

    As global emission regulations and energy-saving policies become increasingly stringent, gasoline engines are facing significant challenges. The urgent technical challenge is to achieve high efficiency and ultra-low emission of gasoline engines. The pre-chamber turbulent jet ignition is one of the most promising technologies for improving the thermal efficiency of gasoline engines and reducing pollutant emission. In this paper, the influence of lean combustion limit expansion and ignition timing on the optimization of thermal efficiency is investigated systematically through three-dimensional flow simulation analysis coupled with a detailed chemical reaction mechanism. The results show that the passive pre-chamber can effectively expand the lean combustion limit, improve the thermal efficiency and reduce the pollutant emission of the engine in comparison with the spark ignition. At an excess air factor of 1.5, the maximum indicated thermal efficiency is 47.24%, which is 11.89% higher than that of the original engine, with the NO x and Soot reduced by 29.27% and 98.76%, respectively.

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    Study on the Influence of Lithium Ion Soft Package Battery Leakage on Electrical Performance and Safety, and Big Data Warning
    Zhaojie Geng,Wenjing Yuan,Rong Huang,Bao Mu,Kangkang Wang,Jingjing Liang
    2024, 46 (9):  1643-1653.  doi: 10.19562/j.chinasae.qcgc.2024.09.012
    Abstract ( 168 )   HTML ( 18 )   PDF (5669KB) ( 240 )   Save

    With the increase of new energy vehicles in the market and battery energy density, thermal runaway events gradually increase. Battery safety issues become particularly important, whereas leakage is one of the key factors inducing battery thermal runaway. In this paper, the influence of leakage on electrical performance and safety is studied by simulating leakage at the cells and modules. At the same time, based on experimental data and remote vehicle data, the characteristics of the leaked battery are extracted and the warning logic is established to achieve online monitoring of the leakage warning. For cells test, a comparative analysis is conducted on the test data of leaking and normal battery cells under cyclic and static states. It is found that compared with normal cells, leaking cells show mass reduction, thickness increase, capacity fade, DC internal resistance increase and dismantling characterization abnormity, which proves that leakage has certain impact on the electrical performance and safety. For module test, characteristics of the thickness and DC internal resistance changes from the parallel units with different leakage degrees are studied. It proves that the thickness and DC internal resistance increase with the increase of leakage degrees, which also augments the potential safety risk of the battery. For vehicle level big data, the pressure difference characteristics of the leaked battery during the starting and ending stages of charge are identified to establish warning and identification logic and conduct online monitoring.

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    Tube-MPC Vehicle Stability Control Based on Stability Domain Division in Extension Phase Plane
    Dongxu Su,Zhiguo Zhao,Kun Zhao,Gang Li,Qin Yu
    2024, 46 (9):  1654-1667.  doi: 10.19562/j.chinasae.qcgc.2024.09.013
    Abstract ( 155 )   HTML ( 13 )   PDF (8277KB) ( 158 )   Save

    For the stability control problem of distributed four-wheel-drive electric vehicles under extreme conditions, considering the influence of sensor noise of yaw rate, lateral and longitudinal acceleration, as well as the estimation error of slip angle, a phase plane stability domain division method based on extension theory and an adaptive Tube-based Model Predictive Control algorithm (ATMPC) are proposed to quickly quantify the stability level of the vehicle and ensure the vehicle driving stability while maintaining tracking accuracy. The designed vehicle yaw stability control system utilizes hierarchical design architecture. The upper layer employs the extension theory to associate the vehicle slip angle-yaw rate phase plane with extension control domain and determines the control domain based on the actual vehicle state and calculates the dependent function to realize the decision-making of the control target weights and modes of the lower layer's Tube-MPC. The lower layer utilizes Tube-MPC to track the desired vehicle slip angle and yaw rate, enabling precise decision-making regarding the yaw moment, and adopts the tire loading ratios optimization method for the allocation of the yaw moment. The control strategy is validated by Carsim/Simulink co-simulation. The results show that the proposed control framework and ATMPC strategy can significantly enhance the driving stability of vehicles in extreme conditions and improve robustness in noisy environments, outperforming traditional MPC.

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    Control Strategy for Dual-Clutch Transmission Gear Shifting Process in Pure Electric Vehicles Based on LADRC
    Bolin He,Yong Chen,Qinglin Dai
    2024, 46 (9):  1668-1677.  doi: 10.19562/j.chinasae.qcgc.2024.09.014
    Abstract ( 88 )   HTML ( 2 )   PDF (5623KB) ( 116 )   Save

    For the uncertainty of the shift control model and parameters and the existing unknown disturbances of the two-speed dual clutch transmission (2DCT) of pure electric vehicles, a linear active disturbance rejection controller (LADRC) method is proposed. Firstly, the dynamic model of the 2DCT shifting process is established, and the shifting process is analyzed. Then, considering the uncertainty and unknown disturbance of the control model, the LADRC controller is applied to the shifting process to track the desired rotational speed, and the Extended State Observer (ESO) is used to estimate the disturbance in real time and compensate for it. Finally, it is compared with the PID control. Simulation and experimental results show that the controller has smaller tracking error and strong robustness, which ensures good gear shifting quality.

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    Research and Application of Reliability Method of Differential System of New Energy Vehicle in Off-road Scene on Sandy Surface
    Xudong Jiang,Zhenghong Li,Minglang Zhang,Huafang Cui,Dapeng Yao,Yiming Zhang
    2024, 46 (9):  1678-1686.  doi: 10.19562/j.chinasae.qcgc.2024.09.015
    Abstract ( 108 )   HTML ( 5 )   PDF (3045KB) ( 238 )   Save

    Based on the current assessment status of the differential system of new energy vehicles, combined with the invalidation problem of the differential system installed on the cross-country type/sport sedan type, in the process of cross-country scene/racing track scene driving test, the application scenes, working principles, damage mechanisms and invalidation forms of the differential system installed on the cross-country type are analyzed in this paper. The Archard damage model is used for damage verification. Based on clustering analysis, the massive real automobile testing data collected from road test are screened and extracted, and then transformed into powertrain bench verification test conditions. The fault of the differential system of the road test automobile is reproduced, forming the reliability assessment ability of the differential system in the sand off-road scenario of new energy vehicles, which provides support for the selection and optimization of differential systems and the development of new automobile models. Meanwhile, this article also has certain reference value on how to improve the performance and reliability of differential systems.

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    Research on Vehicle Airbag Energy Absorption Device for Pedestrian Classification Protection
    Kaibo Yan,Yang Shu,Sisi Lu,Hui Duan,Jie Yang
    2024, 46 (9):  1687-1696.  doi: 10.19562/j.chinasae.qcgc.2024.09.016
    Abstract ( 138 )   HTML ( 12 )   PDF (4755KB) ( 239 )   Save

    Current crash protection research for pedestrians has been conducted primarily on adults, with no classification of adults and children. In this paper, a numerical simulation model of human-vehicle collision is established according to the relevant crash provisions of Euro-NCAP, and the simulation analysis shows that universal airbags cannot effectively reduce the head injuries of adults and children at the same time. Therefore, an airbag energy absorption device for adult and child classification protection is studied according to the characteristics of airbags and the physiological differences between adults and children, and an improved YOLOv5 pedestrian target detection model is proposed to realize the classified recognition of adults and children. According to the classification results, the vehicle control module dynamically adjusts the parameters of the airbag energy absorption device, so that the device can be deployed to different states for adults and children respectively, realizing the classification protection of pedestrians. The results show that the designed target detection model is able to achieve the classification and recognition of pedestrians, with an increase of 3.11% and 4.32% in terms of adult and child category detection accuracy, respectively, compared with the initial model. After installing the airbag energy absorption device, the HIC value of the adult head can be reduced by a maximum of 63.4% and the peak acceleration can be reduced by a maximum of 61.7%, while the HIC value of the child head can be reduced by 31.4% and the peak acceleration can be reduced by 53.2%. The thesis research results can provide scientific theoretical support for the design of pedestrian active and passive safety protection devices.

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    Cockpit Facial Expression Recognition Model Based on Attention Fusion and Feature Enhancement Network
    Yutao Luo,Fengrui Guo
    2024, 46 (9):  1697-1706.  doi: 10.19562/j.chinasae.qcgc.2024.09.017
    Abstract ( 133 )   HTML ( 4 )   PDF (2852KB) ( 200 )   Save

    For the problem of difficulty in balancing accuracy and real-time performance of deep learning models for intelligent cockpit driver expression recognition, an expression recognition model called EmotionNet based on attention fusion and feature enhancement network is proposed. Based on GhostNet, the model utilizes two detection branches within the feature extraction module to fuse coordinate attention and channel attention mechanisms to realize complementary attention mechanisms and all-round attention to important features. A feature enhanced neck network is established to fuse feature information of different scales. Finally, decision level fusion of feature information at different scales is achieved through the head network. In training, transfer learning and central loss function are introduced to improve the recognition accuracy of the model. In the embedded device testing experiments on the RAF-DB and KMU-FED datasets, the model achieves the recognition accuracy of 85.23% and 99.95%, respectively, with a recognition speed of 59.89 FPS. EmotionNet balances recognition accuracy and real-time performance, achieving a relatively advanced level and possessing certain applicability for intelligent cockpit expression recognition tasks.

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    Life Cycle Climate Performance Analysis of Air Conditioning System in Electric Vehicle Charged with Mixed Refrigerant
    Feng Zhou,Xuwen Tian,Hongqi Li
    2024, 46 (9):  1707-1714.  doi: 10.19562/j.chinasae.qcgc.2024.09.018
    Abstract ( 113 )   HTML ( 1 )   PDF (2691KB) ( 192 )   Save

    Air conditioning system as a key subsystem of environmental regulation within the entire vehicle system, the carbon emission of air conditioning system throughout its entire lifecycle is crucial for meeting the environmental protection and emission requirement of electric vehicle. Combining the life cycle climate performance (LCCP) model of electric vehicle air conditioning system with relevant data, the LCCP values in different provinces of China are analyzed in this paper. Besides, the LCCP values under two different heating schemes and different carbon intensities of electricity are compared. The results show that low-GWP mixed refrigerant RE170/R134a (RE170 to R134a mass fraction ratio 90∶10) can lead to a decrease in LCCP values for electric vehicle air conditioning system by 11.2% to 28.1% in China. Replacing the PTC heater with the heat pump results in a decrease in LCCP values by 0 to 33.1%. In addition, considering the future changes in China's carbon intensity of electricity and the proliferation of electric vehicles, it is anticipated that the LCCP values for an individual vehicle by 2035 will decrease by 31.7% to 39.3%, while the gross electric vehicle LCCP values in China will increase significantly.

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    Research on the Influence and Control of Automobile Sheet Metal Vibration on Interior Noise Based on Transmission Path Analysis
    Yongchao Li,Yu Zhao,Huanhuan Chen,Hu Wang,Rongrong Zhang
    2024, 46 (9):  1715-1722.  doi: 10.19562/j.chinasae.qcgc.2024.09.019
    Abstract ( 156 )   HTML ( 8 )   PDF (6042KB) ( 276 )   Save

    The road noise problem in the frequency range of 35-40 Hz generated by a certain vehicle model on rough asphalt pavement at a speed of 30 km/h is analyzed by simulation and testing methods. Based on structural noise transfer path analysis (TPA) and node contribution analysis, it is determined that the problem frequency noise is mainly caused by low-frequency vibration of the vehicle body sheet metal parts. Therefore, based on the partial resonance principle, a resonance structure that can be industrialized according to the shape and local space of the sheet metal is designed, which is composed of a metal bracket and a metal block. By attaching this resonance structure to the sheet metal area with a significant contribution, simulation results show that the structure reduces the vibration of the sheet metal, thereby optimizing the interior noise. The peak noise levels in the front and rear seats are reduced by 8.6 and 6.4 dB, respectively. Meanwhile, the vehicle test results indicate that the interior noise has been improved by 7.0 and 5.8 dB. This provides a new research method and optimization scheme for controlling low-frequency noise caused by vibration of sheet metal.

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