车载动力电池包的有限元分析及轻量化设计

为了实现动力电池包的轻量化,并避免电池包在使用时产生的频率共振问题,对动力电池包的3种典型工况进行结构强度分析及模态响应分析.采用变密度法建立了以电池包柔度最小为优化目标、单元节点位移为设计变量、电池包的刚度和模态为约束条件的优化数学模型,对电池包上盖进行形貌优化.根据优化结果对电池包进行结构改进,改进后的电池包强度、...     

基于某车型动力电池包的随机振动疲劳分析与结构设计改进

基于随机振动理论与频域疲劳分析方法,利用有限元软件构建动力电池包随机振动疲劳失效分析模型并计算结构的疲劳寿命,分析结果与试验结果完全吻合。分析结构的失效机理并进行结构设计改进,试验结果表明,改进方案的疲劳寿命得到显著的提高,具有较好的抗振耐久性能。     

某电动汽车动力电池箱随机振动仿真与试验

为保证装载在新能源汽车上的动力电池包在实际道路上运行的可靠性及安全性,需对电池包进行随机振动工况的可靠性验证。本文基于通用有限元软件ANSYS,对某动力电池汽车的动力电池箱进行随机振动工况下的仿真计算。最后通过随机振动试验对仿真分析结果进行了对比验证,保证有限元方法的正确性,得出了基于仿真分析的随机振动工况动力电池强度评估标准。     

混合动力客车车身骨架轻量化设计

利用HyperMesh软件对混合动力客车进行静态分析和模态分析,使用相对灵敏度的方法筛选出对客车刚度和客车模态影响小但对质量影响大的构件,将其厚度作为设计变量,以客车质量最小、扭转刚度最大为目标对客车进行多目标优化,并对比优化前后模型的结构性能.分析结果表明,在各项性能变化不大,在满足设计要求的条件下,客车车身骨架质量减少259kg,轻量化程度达到10.67％,取得了较大的轻量化效果,同时说明了客车骨架结构轻量化设计方案的有效性.     

基于模糊自适应滑模方法的混联式混合动力客车模式切换协调控制

在混联式混合动力汽车纯电动至并联驱动模式切换过程中,由于发动机、电动机及离合器瞬态特性的影响,可能导致动力系统输出转矩的突变从而使车辆产生较大的纵向冲击。以混联式混合动力客车为研究对象,考虑发动机和电动机瞬态响应特性的显著不同,针对离合器在结合过程中的运行状态,以提高驾驶性能为目标设计出混合动力客车纯电动至并联驱动模式切换协调控制策略。协调控制采用模糊自适应滑模方法,其中模糊自适应系统用于估计系统参数不确定性引起的偏差以及发动机实际输出转矩与目标转矩的偏差,估计出的偏差值用于调整滑模控制器的控制量,从而提高控制系统的控制精度和鲁棒性。通过仿真及实车试验验证控制策略的有效性。结果表明,设计的控制策略在模式切换过程中满足驾驶员动力需求的前提下使动力系统输出转矩的波动范围和最大冲击度分别下降85%和78%,从而显著提高了混合动力客车的驾驶性能。     

机械外力下动力电池包的系统安全性分析与评价

动力电池包是一个复杂系统综合体,对复杂系统而言仅考虑组件的可靠安全性并不能保证其系统的安全性,迫切需要从系统层面分析评价动力电池包的安全性。运用复杂系统安全理论结合电动汽车实际工况,提出基于整体精细化模型可量化、层次化的动力电池包系统安全性评价。保证单体锂电池模型精细化的情况下,从正碰、侧碰、振动冲击三种常见工况对动力电池包进行仿真分析,采用层次分析(AHP)和模糊综合评价(FCE)相结合的方法对影响动力电池包系统安全的关键因素指标进行综合性安全评价。结果表明动力电池包系统安全性等级较低,安全性能较差。所提方法可为动力电池包正向结构设计和系统安全改善等工作提供参考。     

电动汽车动力电池包结构设计分析研究进展

动力电池包是电动汽车的核心模块之一,有严格的安全性和轻量化的要求,必须通过规范的结构分析和优化来实现.简述动力电池包发展现状、总装结构设计要点以及结构设计流程,总结其结构动力学分析和温度场仿真模拟的研究进展,明确指出建立精细化有限元模型、进行温度场模拟的电池包动力学性能分析与结构优化是进一步提高电池包研发水平的重要方向...     

基于有限元的全铝车身客车结构强度和刚度分析

应用ANSYS分析全铝车身客车在弯曲工况、制动工况以及转向工况下的结构强度和刚度。结果表明,该全铝车身客车满足结构强度和刚度的设计要求,可为客车车身轻量化提供可靠依据。     

某三段式客车车身骨架有限元分析

建立某三段式客车车身骨架有限元模型,利用有限元模型,分析该客车车身骨架在多种工况下的刚度和强度,并对该客车车身骨架结构进行了模态分析。     

蒙皮对客车车身结构强度和刚度的影响

采用有限元法,以ＹＺ１６７００Ｃ轻型客车为研究对象,根据计算结果研究和分析了蒙皮对客车车身结构强度和刚度的影响,为客车车身设计和结构强度分析提供了有价值的理论依据。     

大型客车车身骨架轻量化设计研究

建立了某全承载式客车车身骨架有限元模型,对车身骨架结构进行了静态分析与模态分析。在保证车身强度和刚度的条件下,提出钢铝一体化轻量化结构方案。以轻量化为目标计算铝合金型材的截面尺寸,完成客车车身骨架的轻量化设计。对轻量化后的钢铝一体化车身骨架进行了校核,并与原车身骨架进行了质量、静态、动态性能的比较分析。分析结果表明,轻量化后的强度和固有频率与之前相当,轻量化效果明显。     

一种新型混合动力城市客车的开发

针对城市公交客车的实际运行工况需要,开发出一种新型混合动力总成装置,用于混合动力城市公交客车。混合动力总成具有高低速双电机模式,能充分发挥串联式和并联式优点。混合动力客车具有纯电、混联、驻车发电和电网充电4种工作模式,使发动机、发电机、电机等部件更优化地匹配工作,在结构上保证了在复杂的工况下系统工作在最优状态,达到更高的节能和减排目标。     

Estimation method of state-of-charge for lithium-ion battery used in hybrid electric vehicles based on variable structure extended kalman filter

Since the main power source of hybrid electric vehicle(HEV) is supplied by the power battery, the predicted performance of power battery, especially the state-of-charge(SOC) estimation has attracted great attention in the area of HEV. However, the value of SOC estimation could not be greatly precise so that the running performance of HEV is greatly affected. A variable structure extended kalman filter(VSEKF)-based estimation method, which could be used to analyze the SOC of lithium-ion battery in the fixed driving condition, is presented. First, the general lower-order battery equivalent circuit model(GLM), which includes column accumulation model, open circuit voltage model and the SOC output model, is established, and the off-line and online model parameters are calculated with hybrid pulse power characteristics(HPPC) test data. Next, a VSEKF estimation method of SOC, which integrates the ampere-hour(Ah) integration method and the extended Kalman filter(EKF) method, is executed with different adaptive weighting coefficients, which are determined according to the different values of open-circuit voltage obtained in the corresponding charging or discharging processes. According to the experimental analysis, the faster convergence speed and more accurate simulating results could be obtained using the VSEKF method in the running performance of HEV. The error rate of SOC estimation with the VSEKF method is focused in the range of 5%to 10%comparing with the range of 20%to 30%using the EKF method and the Ah integration method. In Summary, the accuracy of the SOC estimation in the lithium-ion battery cell and the pack of lithium-ion battery system, which is obtained utilizing the VSEKF method has been significantly improved comparing with the Ah integration method and the EKF method. The VSEKF method utilizing in the SOC estimation in the lithium-ion pack of HEV can be widely used in practical driving conditions.     

Intelligent vehicle electrical power supply system with central coordinated protection

The current research of vehicle electrical power supply system mainly focuses on electric vehicles (EV) and hybrid electric vehicles (HEV). The vehicle electrical power supply system used in traditional fuel vehicles is rather simple and imperfect;electrical/electronic devices (EEDs) applied in vehicles are usually directly connected with the vehicle’s battery. With increasing numbers of EEDs being applied in traditional fuel vehicles, vehicle electrical power supply systems should be optimized and improved so that they can work more safely and more effectively. In this paper, a new vehicle electrical power supply system for traditional fuel vehicles, which accounts for all electrical/electronic devices and complex work conditions, is proposed based on a smart electrical/electronic device (SEED) system. Working as an independent intelligent electrical power supply network, the proposed system is isolated from the electrical control module and communication network, and access to the vehicle system is made through a bus interface. This results in a clean controller power supply with no electromagnetic interference. A new practical battery state of charge (SoC) estimation method is also proposed to achieve more accurate SoC estimation for lead-acid batteries in traditional fuel vehicles so that the intelligent power system can monitor the status of the battery for an over-current state in each power channel. Optimized protection methods are also used to ensure power supply safety. Experiments and tests on a traditional fuel vehicle are performed, and the results reveal that the battery SoC is calculated quickly and sufficiently accurately for battery over-discharge protection. Over-current protection is achieved, and the entire vehicle’s power utilization is optimized. For traditional fuel vehicles, the proposed vehicle electrical power supply system is comprehensive and has a unified system architecture, enhancing system reliability and security.     

客车车身有限元分析

为了研究客车车身在不同工况下的受力和变形,对某半承载式客车车身的结构进行了分析和实体测绘,得到建模的基本数据,通过合理的简化建立了车身三维几何模型。定义了模型单元并对车身几何模型进行了有限元网格划分,定义了边界约束条件,建立了车身有限元模型。在弯曲、扭转、急转、制动4种不同工况下,对半承载式客车车身模型进行了强度和刚度校核。结果表明:该客车车身能够满足强度和刚度设计要求,同时在车身等强度和轻量化设计方面有优化空间。     

Operation algorithm for a parallel hybrid electric vehicle with a relatively small electric motor

In this paper, operation algorithms for a parallel HEV equipped with a relatively small motor are investigated. For the HEV, the power assist and the equivalent fuel algorithms are proposed. In the power assist algorithm, an electric motor is used to assist the engine which provides the primary power source. In the equivalent fuel algorithm, the electric energy stored in the battery is considered to be an equivalent fuel, and an equivalent brake specific fuel consumption for the electric energy is proposed. From the equivalent fuel algorithm, distribution of the engine power and the motor power is determined to minimize the fuel consumption for a given battery state of charge (SOC) and a required vehicle power. It is found from the simulation results that the fuel economy and the final battery SOC depend on the motor discharge energy and it is the best way to charge the battery only by the regenerative braking, not by the engine to improve the overall fuel efficiency of the HEV with the relatively small motor.     

动力蓄电池包挤压失效仿真与实验

为提高动力蓄电池包挤压仿真的精度,将延性损伤准则引入到有限元仿真,通过单轴拉伸试验、纯剪切试验与缺口件拉伸试验与有限元仿真,获得了某动力蓄电池包结构所用材料6061-T6铝合金的延性损伤参数。型材三点弯曲试验、动力蓄电池包挤压试验与有限元仿真的结果表明:输入延性损伤参数的有限元仿真结果与试验结果误差小,能较为准确地模拟铝合金损伤对结构承载性能的影响;不考虑材料失效的结果与试验结果误差较大。     

轻型车有限元分析及应用

采用有限元法分析了ＨＢ６７００型客车车身、车架的静态强度、刚度和固有频率及振型，对改进设计提供了有价值的理论依据。经实车运行验证了计算的正确性。     

混合动力汽车控制策略的研究现状及其发展趋势

对混合动力汽车的结构型式进行分类,HEV的动力系统基本可分为串联式、并联式和混联式3种,对并联型和串联型混合动力汽车控制策略研究现状进行分析。混联式混合动力系统结合了串联式和并联式两种结构的优点,使得能量流动的控制和能量消耗的优化具有更大的灵活性和可能性,并对混联式结构的几种控制方案进行了分析。指出混合动力汽车的控制策略不十分完善,需要进一步优化。控制策略不仅仅要实现整车最佳的燃油经济性,而且还要兼顾发动机排放、蓄电池寿命、驾驶性能、各部件可靠性及整车成本等多方面要求,并针对混合动力汽车各部件的特性和汽车的运行工况,使发动机、电动机、蓄电池和传动系统实现最佳匹配,兼顾上述各方面要求的优化控制策略的研究应是今后的研究重点。     

城市客车的结构轻量化设计

这里建立了城市客车车身和车架结构的有限元模型，进行了该结构在多种工况下的强度分析、刚度分析以及增加强度的结构改进设计，进一步提出了该车型结构的轻量化设计方案，并通过强度分析和刚度分析确认了轻量化设计方案。