In order to meet the needs of charging safety, service experience of high-power DC charging piles and improve their power utilization, this paper proposes a flexible power allocation control strategy. Based on the topology of circular power allocation, the power allocation control timing and algorithm for charging start, charging in progress and release at the end are designed. The utilization rate of power nodes is improved by static and dynamic polling switching. To ensure stable operation of the system, the definition of minimum remaining required power is introduced, and the difference in remaining required power, the number of switching times in a single insertion gun, and the filtering time are comprehensively judged to avoid frequent switching. Verification result shows that this strategy can improve average power utilization rate from 1.76% to 2.24%, demonstrating significant optimization effect.

This paper investigates discrepancies between the conducted emission test results of the On-Board Charger (OBC) and those of the vehicle-level alternating current charging system. Starting from the testing mechanisms, the paper systematically analyzes the correlation between the OBC’s electromagnetic interference characteristics and the vehicle-level test conditions. Through combined simulation and experimental validation, the paper proposes a component-level conducted emission interference control scheme. By ensuring component-level electromagnetic compatibility performance, the scheme enables pre-validation of vehicle-level standard requirements, thereby provides support for the forward development of electromagnetic compatibility in new energy vehicles.

In order To evaluate and predict the Electromagnetic Compatibility (EMC) performance of DC/DC converter in the early stage of design, the mainstream electromagnetic compatibility “three elements” method is first used to analyze the main interference source and propagation path of DC/DC converter. Secondly, based on the high-frequency parameter theory of transformer, the parasitic parameter theory of Printed-Circuit Board (PCB) and the parameter extraction method of common mode chokes, the common mode interference of transformer, PCB wiring and common mode chokes are analyzed separately. The high-frequency equivalent model of transformer and PCB, experimental environment test benches and high-voltage filtering modules are established using Maxwell, HFSS, SIwave, and Q3D software in the ANSYS simulation platform. Finally, the integration of each module of DC/DC converter and the simulation analysis of conduction and radiation emission are completed in Simplorer software. The results indicate that the conducted and radiated interference exceeds the standard more severely in the Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) switching frequency band and its harmonics of the main interference source. The model simulation results are basically consistent with theoretical analysis and actual experimental results, and the simulation model has high accuracy.

To reduce injuries of through-type headlamp to pedestrians’ pelvic limb in collisions, a series of pedestrian upper leg impact tests are designed to evaluate the crash response characteristics of a car equipped with through-type headlights at different impact points. The test results show that when the upper leg collides with the middle area of the headlamp, the impact force peak value reaches up to 6 424 N, the injury risk is very high. The paper proposes two optimizations to headlamp including low-temperature treatment and increasing initial injury, and a series of test are performed. The results show that the risk of injury to pedestrians’ legs is reduced by reducing the structural toughness of the through-lamp lampshade by low-temperature treatment which cause the lampshade crack at early stage, which effectively reducing impact force peak value and improving the energy absorption capacity in collisions. In contrast, the effect of only weakening toughness of interior plastic parts is not obvious.

To rapidly and accurately predict the crashworthiness indicators of thin-walled tubes, a bionic gradient circular multi-cell thin-walled tube axial compression model for predicting the average collision force is established based on the Simplified Super Folding Element (SSFE) theory, and a Long Short-Term Memory (LSTM) network model is built to predict the crashworthiness indicators of the bionic gradient circular multi-cell thin-walled tube under different geometric parameters. The results show that the theoretical prediction error is less than 6% compared with the simulation results, indicating the reliability of the theoretical model. The LSTM network model exhibits an error of less than 2% for Energy Absorption (EA) and Initial Peak Force (IPF) on the validation set, and an error of less than 5% on the test set, demonstrating excellent prediction accuracy and generalization capability.

In order to reduce the risk of passenger lower leg injuries in crash test, this paper analyzes the influencing factors of dummy lower leg injuries based on a large number of test data, and then studies the influence of passenger foot posture on lower leg injuries through leg impact test and simulation. The results show that the direct cause of foot injury is the excess lower tibial moment M_y value. Lower leg injuries could be effectively reduced by adjusting the foot posture. When the foot is tilted forward by 10°, the lower tibial moment M_y is 94.21 N·m, and the tibial index T_i is 0.44, which could be reduced by 37% compared with the standard foot posture.

The resrearch aims of the paper is to improve the optimization efficiency of the automobile sill beam, and address the challenges of optimization such as the limited energy absorption of the sill extrusion aluminum under the condition of the side column collision, long iterative cycle of explicit solution in the simulation and the high requirements of the manufacturing process. A collision model is established based on an SUV model, and the Design Of Experiment (DOE) analysis is made with sill beam thickness as variables, resulting in 144 groups of valid design data are obtained. A Reduced-Order Model (ROM) is formed by deep learning methods(Rapidminer, romAI) and used as the alternative model of optimization and simulation. The results of CAE simulation verifies that accuracy of romAI reaches more than 95% in optimization and the solution speed is increased by more than 40 times under the limited data, which greatly shortens the R&D cycle.

In order to analyze pedestrian leg crash injury in active and passive safety fusion scenes with intervention of Automatic Emergency Braking (AEB) system, this paper firstly compares and analyzes THUMS (Total Human Model for Safety) human body finite element model and advanced Pedestrian Legform Impactor (aPLI), then selects THUMS dummy model with higher biological fidelity to study the influence rule of collision speed and vehicle body posture on leg injury index with the intervention of AEB system. The results show that the motion response of THUMS dummy is closer to practical collision state compared with aPLI. With the change of collision speed and vehicle body posture, different types of vehicles show different leg-type injury rules at different collision positions, and the influence of collision speed on leg injury index is greater than that of vehicle pitch attitude. The increase of vehicle pitch angle and the decrease of collision speed will cause the decrease of upper leg collision speed, but it has no obvious effect on the collision angle. The change of collision speed and vehicle body posture will affect the collision posture of pedestrian leg and vehicle, thus influencing various leg injury indicators. Therefore, the impact of vehicle body braking on pedestrian collision should be considered in the pedestrian lower limb injury evaluation system, so as to evaluate the pedestrian lower limb injury more comprehensively and objectively.

In the safety property development of side pole under crash condition, the relationship between vehicle structural characteristics (such as initial side space, speed waveform) and occupant injury is not uncertain, and there are few strategies for matching side airbags to vehicle structural characteristics. In order to address the above issues, this paper proposes a lateral Pole collision Occupant Load Criterion (POLC) to correlate the structural characteristics of the vehicle’s side structure and occupant injuries, and categorize vehicles into two groups based on the relative magnitude of their POLC values to the occupant’s average acceleration tolerance limit a_{ave_max}. For a given vehicle A with a POLC value less than a_{ave_max}, the paper analyzes deformation of the side airbag matched for the vehicle from the perspective of occupant kinematics, then analyzes whether the side airbag stress-deformation curve meet occupant protection demand from the perspective of stress limit of occupant torso, in an attempt to provide a theoretical basis for the design of vehicle side structure characteristics at the early stage of vehicle crash safety development.

In order to enhance the testing and evaluation of systematicness and comprehensiveness of Moving Off Information System (MOIS) for commercial vehicles, the paper analyzes the evaluation requirements of commercial vehicle MOIS, clarifies the working principle of MOIS, and proposes specific testing and evaluation plans and improvement measures. Commercial vehicles with the same MOIS perception and recognition scheme but different sizes are used as test samples, the alarm triggering and ending timing, alarm duration, etc. of MOIS are evaluated and analyzed for different target objects, blind spot positions, and bias rates. The results show that the same scheme of MOIS installed on commercial vehicles of different sizes can meet regulatory requirements, and the monitoring effect of the system on the forward blind spot shows a trend of right side>left side>middle. Moreover, when the vehicle moves together with the longitudinal target object in front, the larger vehicle has better blind spot monitoring effect.