燃料电池汽车转向系统综述

介绍燃料电池汽车转向系统的要求与特点,综述现有适合燃料电池汽车的电动液压助力转向系统、电动助力转向系统技术及未来线控转向系统技术,分析各自的特点,并阐述了燃料电池汽车转向系统的应用与发展趋势。     

某氢燃料车型液压助力转向系统匹配设计

随着液压助力转向系统的不断应用与发展,人们对转向系统的要求越来越高。文章结合某氢燃料车型液压助力转向系统的设计,就该系统中的转向器和电动转向泵压力和流量进行匹配设计,对转向器垂臂摆角、转向油管的内径和油罐的容积、转向直拉杆的间隙和强度等进行设计和校核,确保了转向系统的安全性和合理性。     

基于阿特金森循环的电动汽车增程器开发

增程式车用发动机更加关注电驱动车辆行驶工况下,电机驱动功率-道路行驶阻力功率平衡状态时的发动机燃油经济性.基于这种特点,开发了一种增程式电动车辆专用发动机,发动机工作循环采用基于阿特金森循环的高膨胀比设计,发动机可以提供额定35 kW的发电功率输出.匹配车辆后,对比同等动力水平下的传统奥托循环发动机与阿特金森循环增程器...     

燃料电池汽车电动液压助力转向系统设计研究

电动液压助力转向系统的设计研究在燃料电池汽车整车开发中有着非常重要的意义。文章介绍了燃料电池汽车电动液压助力转向系统设计及不同的系统控制设计方案,并进行对比分析,得出了较优的燃料电池汽车转向系统设计方案。研究结果对燃料电池汽车电动液压助力转向系统的开发设计具有重要的参考价值。     

干式复合带无级自动变速器系统与速比电机控制策略的研究

介绍了一种干式复合带无级自动变速器(A-CVT)的结构及T作原理。该变速器不仅减少了成本昂贵、结构复杂的液力或电液装置，还改善了汽车的燃油经济性和发动机的排放。利用装有A-CVT的MatizⅡ轿车为试验车开发了A-CVT的电控系统，并对A-CVT中速比电机的控制策略进行了较为详细的讨论。在MatizⅡ轿车上长时间的试用和测试表明，该电控系统使样车基本达到了原车的性能指标。     

液压技术在混合动力汽车节能方面的应用

随着我国经济的不断发展和汽车工业技术水平的提高,人们对生活环境提出了更高层次要求,其中混合动力轿车就是一个很好地研究方向。本文介绍几种液压传动系统、燃油发动机控制系统以及电动助力转向系统等。通过对比分析国内外混合动力系统在节能方面应用现状及存在问题;最后针对该课题进行展望并总结出一些自己对于今后工作所做出的意见与建议:从油耗和排放两个方面对技术发展前景做了简要阐述,提出未来发展中应注意的关键点。     

混合动力汽车发动机起动/停机控制

介绍了采用继电器对发动机管理系统ECU的工作进行控制,同时针对发动机管理系统原有的减速断油模式进行了重新标定,实现了发动机高转速起动功能,且降低了停机时的转速,避免了对发动机ECU频繁的通/断电操作及因频繁起动造成的发动机燃油消耗率和排放性能的不良影响。     

Dynamics characteristics analysis and control of FWID EV

Compared with internal combustion engine (ICE) vehicles, four-wheel-independently-drive electric vehicles (FWID EV) have significant advantages, such as more controlled degree of freedom (DOF), higher energy efficiency and faster torque response of an electric motor. The influence of these advantages and other characteristics on vehicle dynamics control need to be evaluated in detail. This paper firstly analyzed the dynamics characteristics of FWID EV, including the feasible region of vehicle global force, the improvement of powertrain energy efficiency and the time-delays of electric motor torque in the direct yaw moment feedback control system. In this way, the influence of electric motor output power limit, road friction coefficient and the wheel torque response on the stability control, as well as the impact of motor idle loss on the torque distribution method were illustrated clearly. Then a vehicle dynamics control method based on the vehicle stability state was proposed. In normal driving condition, the powertrain energy efficiency can be improved by torque distribution between front and rear wheels. In extreme driving condition, the electric motors combined with the electro-hydraulic braking system were employed as actuators for direct yaw moment control. Simulation results show that dynamics control which take full advantages of the more controlled freedom and the motor torque response characteristics improve the vehicle stability better than the control based on the hydraulic braking system of conventional vehicle. Furthermore, some road tests in a real vehicle were conducted to evaluate the performance of proposed control method.     

汽车助力转向技术及其控制策略的研究

汽车转向系统发展至今,已经历了机械转向、液压助力转向、电控液压转向、电动助力转向、主动转向、后轮随动转向、线控转向和操纵手柄式转向等形式。本文对各种助力转向系统技术及控制策略进行研究,为转向系统的进一步研究提供理论基础。     

Development of an electric motor-driven pump unit for electro-hydraulic power steering with 42V power-Net

Motorization in vehicles is expanding rapidly for fuel efficiency, customer comfort, convenience, and safety features. These new electric loads represent an increase in the required electric power. This has generated interest in new, higher power systems such as the 42V Power Net. The electro-hydraulic power steering (EHPS) system is one of these systems. This paper presents the development of the electric motor-driven pump unit for the EHPS system using a 42V power-Net. The interior type permanent magnet synchronous motor (IPMSM) can be applied to this system with more power density per volume for compactness of the EHPS. In order to improve the system, the IPMSM and its control method was optimized for improved torque characteristics and electric power consumption. The performances of both the pump unit and the IPMSM have been verified by experimental results. Finally, all in one type the electric motor-driven pump unit are developed from the experiment verification.     

Stability enhancement and fuel economy of the 4-wheel-drive hybrid electric vehicles by optimal tyre force distribution

In this paper, vehicle stability control and fuel economy for a 4-wheel-drive hybrid vehicle are investigated. The integrated controller is designed within three layers. The first layer determines the total yaw moment and total lateral force made by using an optimal controller method to follow the desired dynamic behaviour of a vehicle. The second layer determines optimum tyre force distribution in order to optimise tyre usage and find out how the tyres should share longitudinal and lateral forces to achieve a target vehicle response under the assumption that all four wheels can be independently steered, driven, and braked. In the third layer, the active steering, wheel slip, and electrical motor torque controllers are designed. In the front axle, internal combustion engine (ICE) is coupled to an electric motor (EM). The control strategy has to determine the power distribution between ICE and EM to minimise fuel consumption and allowing the vehicle to be charge sustaining. Finally, simulations performed in MATLAB/SIMULINK environment show that the proposed structure could enhance the vehicle stability and fuel economy in different manoeuvres.     

混合动力汽车燃油经济性研究

应用能量分析的方法,以轿车和载货汽车为例,研究了混合动力汽车(HEV)与传统燃油发动机汽车的燃油经济性。发现按原车后备功率最大值时所对应的车速所需的驱动功率作为HEV燃油发动机功率的选择依据,节油效果最显著。当燃油驱动功率和电动驱动功率各占50%左右时,HEV轿车的经济性评价指标为原车的22.8%,HEV货车的经济性评价指标为原车的79.2%,同时又能保证动力性基本不变。结果表明,用混合动力可以有效地降低汽车的100km燃料消耗量,轿车的燃料消耗降低幅度大于货车。     

Development of equivalent fuel consumption minimization strategy for hybrid electric vehicles

Power distribution between an internal combustion engine and electric motors is one of main features of hybrid electric vehicles that improves their fuel economy. An equivalent fuel consumption minimization strategy can instantaneously identify the optimal power distribution by converting the battery power into the equivalent fuel power and minimizing the overall fuel consumption. To guarantee the effectiveness of the strategy, it is essential to find the proper value of the conversion factor used to obtain the equivalent fuel power. However, finding the proper value is not a straightforward process because it is necessary to consider the overall power conversion efficiencies and battery charge sustaining strategy for the target driving cycle in advance. In this study, a model-based parameter optimization method is introduced to find the optimal conversion factor. A hybrid electric vehicle simulation model capable of estimating fuel consumption was developed, and the optimal conversion factor was discovered using a genetic algorithm that evaluates its population members using the simulation model. A series of simulations and vehicle tests was conducted to verify the effectiveness of the optimized strategy, and the results show a distinct improvement in fuel economy.     

混合动力系统发动机工况点优化的标定实现

混合动力系统较传统动力总成系统增加了电机、电池,使发动机工况点可以在发动机、电机、动力电池限制范围内进行优化,以提高燃油经济性。以优化整车燃油经济性为目的,得到所有可运行工况点发电、助力工作模式下的等效燃油消耗率。等效燃油消耗率为非线性离散数据,为保证标定数据有效、整车系统的稳定性,给出基于等效燃油消耗率的发动机工况点标定数据修正原则,最终得到混合动力系统扭矩分配的标定数据。通过合理标定扭矩分配,达到优化发动机工况点落点以提高整车经济性的目的。     

浅谈智能驾驶对转向系统的发展影响

随着汽车及零部件行业的飞速发展,助力转向系统技术也得到了飞速发展和更新换代,从最初的机械助力转向,到液压助力转向,再到电动助力转向系统。尤其是随着当前汽车行业智能驾驶和车联网的发展,电动助力转向系统的高级功能开发和技术进一步提速,通过冗余设计从而来支持整车自动驾驶技术。     

发动机热管理系统对整车节油性能的评估

优化车辆发动机热管理的结构形式与控制模式是提高车辆节油性能的重要途径,本文在公交客车平台基础上,比较了基于电动风扇冷却的新型发动机热管理系统与由皮带直驱的风扇冷却系统,阐述基于电动风扇冷却的发动机热管理系统对整车节油性能的贡献。     

YC6108ZQ型车用柴油机的开发

在ＹＣ６１０８ＺＱ型柴油机基础上，采用废气涡轮增压技术，并对气缸体、曲轴、进排气系统、系统和供油系统等进行了高度改进。改进后的ＹＣ６１０８ＺＱ柴油机提高了功率、增大了扭矩，同时获得了较低的噪声、排放、低油耗等综合性能指标。通过装车考核，表明该机具有良好的动力性、经济性和适应性。     

并联式混合动力客车传动系设计与仿真

对混合动力客车（HEB）的传动系种类进行分析与探讨,设计某种并联式HEB的传动系,在MATLAB／SIMLINK仿真环境下,在满足车辆动力性要求的前提下,利用ADVISOR软件,以燃油经济性为主要目标,确定传动系主要部件的具体参数,并与纯内燃机客车的仿真进行比较分析。     

Optimization of power management among an engine,battery and ultra-capacitor for a series HEV: A dynamic programming application

In a hybrid electric vehicle (HEV) system, it is an important issue on how to distribute the output power from multiple power generating components to operate a vehicle more efficiently. Many studies have been conducted on how to manage multiple power sources of a vehicle based on various optimization theories. In this study, an algorithm to calculate the optimization of a series HEV that has three power generating components, engine, battery and ultra-capacitor, is developed based on dynamic programming. Normally dynamic programming is applied to the optimization of power management and components sizing by estimating potential fuel economy for electrified vehicle such as HEV, Plug-in HEV or Fuelcell HEV. In contrast with most objective systems that have only two power generating components, the system in this study has three power sources. Since the system has three power sources, the number of state and control variables of optimization problem increases. Therefore the number of calculations increases unreasonably. To decrease the number and time of calculations, a new electric model that contains the both characteristics of battery and ultra-capacitor is developed with some assumptions. In comparison with the optimization algorithm which follows the theory of DP with no assumptions, the results from the newly developed algorithm has 1.04 % discrepancy in terms of fuel economy, even though the calculation time decreases to 4400 times less.     

基于增益功率燃油系数的HEV能量管理策略

为了优化等效燃油最小能量管理策略的节油效果，以适用于工程批量应用为导向，制定基于增益功率燃油系数的混合动力汽车(HEV)能量管理策略。基于瞬时优化原理，提出基于增益功率燃油系数的工作模式决策机制，根据电机发电或电动引起的发动机功率与燃油消耗率的变化关系，分别给出电机充电和放电模式下增益功率燃油系数的计算方法。考虑发动机扭矩瞬态快速变化对油耗的影响和电机及电池包充放电效率特性，提出发动机高效区域扭矩滞回控制方法，建立基于增益功率燃油系数的能量管理策略算法架构。基于MATLAB/Simulink搭建控制策略软件模型，通过转鼓试验台进行实车试验验证。研究结果表明：相对于等效燃油最小能量管理策略，基于增益功率燃油系数的能量管理策略提升了节油率和舒适性，在全球轻型汽车测试循环(WLTC)工况下的百公里油耗降低了约4.8%，发动机的启停次数降低了约53%；相对于有效燃油消耗率(BSFC)最优工作点控制方法，发动机高效区域滞回控制方法降低百公里油耗约1.8%；与采用基于动态规划的全局优化能量管理策略的仿真结果对比，在不能提前预知工况的条件下，制定的能量管理策略在WLTC工况与新标欧洲测试循环(NEDC)工况下的油耗与理论最优值差距均较小。