Effects of FTP-75 mode vehicle fuel economy improvement due to types of power steering system

This paper focuses on fuel economy improvement according to the type of power steering system. Usually, a conventional power steering system is directly driven by the crankshaft of the engine with a belt, known as HPS (hydraulic power steering). However, there is some inefficiency with this system at high engine speeds. To improve this inefficiency, automobile makers have developed two power steering systems: EHPS (electro-hydraulic power steering) and MDPS (motor-driven power steering) or EPS (electric powered steering). However, there has been insufficient study of effects of the type of power steering system on fuel economy. In this paper, the effect of the type of power steering system on fuel economy is studied experimentally, and calculations of the effect on vehicle fuel economy are presenting using computer simulation with AVL cruise software. The results demonstrate that a 1% vehicle fuel economy improvement can be achieved in a vehicle with an electro-hydraulic power steering system compared to a vehicle with a hydraulic power steering system. In addition, a 1.7% vehicle fuel economy improvement can be achieved using a full electric power steering system in a FTP-75 driving cycle. These results could be used to choose a power steering system.     

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。     

电动液压助力转向系统控制算法研究与实现

研究了电动液压助力转向控制系统中转向盘角速度、车速和电机转速之间非线性关系的控制算法,并依据实际控制系统参数,得到该控制系统中车速、电机转速及转向角速度三者的非线性关系,利用仿真软件实现了控制系统所需要的助力曲线。通过在AMESIM中仿真对比表明,运用该算法能够得到较理想的助力曲线,验证了该算法在电动液压助力转向系统中应用的可行性。通过台架试验表明,该系统助力效果明显,控制算法中参数变换对控制系统的影响与实际控制系统控制效果相吻合。     

柴油机电控系统平台开发及应用

介绍了柴油机单体泵电控系统平台化开发内容:ECU硬件开发、上层驱动和应用层开发、底层驱动开发、操作系统及任务调动。提出了V型开发流程、软件CMMI开发方法等规范的开发流程方法。对应用该平台化方法开发的柴油机单体泵电控系统进行试验,验证了该平台开发方法的有效性。     

基于某重型商用车42V稀土永磁ISG的控制研究

42V电器系统是国际上研究的热点,起动/发电一体机(ISG)是42 V电器系统的核心部件。针对42 V大扭矩(600 Nm)稀土永磁ISG设计了可变结构的功率变换器拓扑,通过对功率变换器的串联和并联切换控制,实现了稀土永磁电机低速时大扭矩输出和高速时发电电压可控,同时提出两路分频错相的斩波控制方法,解决了电机绕组需要高斩波频率,功率开关管斩波频率低的问题。     

Thermal anaysis of an electric water pump for internal combustion engine vehicles

An electric water pump for engine cooling system has an advantage which particularly in the cold start, the use of the electric water pump saves fuel and leads to a corresponding reduction in emissions. However, the electric water pump for internal combustion engine generates much more heat loss than that for hybrid electric vehicle or electric vehicle since it is operated by electric power of high current and low voltage. In this study, the fluid flow and thermal characteristics of the canned type electric water pump with an inverter integrated has been investigated under the effects of heat generation. The analysis conditions such as outdoor air temperature of 125°C, water pump speed of 6000 rpm, coolant temperature of 106°C and coolant flow rate of 120 L/min were used as a standard condition. Therefore, the thermal performance of the canned type electric water pump’s motor and inverter was evaluated by comparison with that of mechanical seal type. In the motor, the temperature reduced by over 10°C, and in the inverter, the amount of temperature decrease equaled to the maximum temperature difference, about 18.7°C. Also, canned type electric water pumps of variable materials were compared for the evaluation of thermal transfer performance for variable thermal conductivity of a can. The motor and inverter were cooled lower to 42°C at motor and about 40°C at inverter for reasonable selection of can’s thermal conductivity.     

电动转向油泵单元在新能源客车上的应用

介绍了电动转向油泵单元的组成及特点,重点阐述了电动转向油泵单元的选型及在新能源客车上的应用,并测量了电动转向油泵单元的噪声,为后续优化设计提供了依据。     

电动汽车PCU系统功能安全开发及测试方法研究

PCU系统作为电动汽车整车上的关键电控系统,其功能安全技术水平直接影响整车安全。本文基于某款混动车型搭载的PCU系统的功能安全V模型开发过程,从整车层面给出了相关项定义、危害分析和风险评估、安全目标、功能安全要求、技术安全要求,并在V模型开发右侧以故障注入测试为例给出了功能安全验证和确认方法示例,为开展PCU系统功能安全正向开发提供借鉴和参考。     

国际汽车电子技术发展新动态——42V汽车供电系统

汽车电子控制技术和智能化的发展趋势，使得汽车电子附件所占的比例和相应耗电量大幅提高，现有12V供电系统对汽车未来产品的供电能力不足是汽车业提出高电压供电系统的直接原因。使用42V供电系统可对发动机、电动制动系统、电动离合器、电动动力转向系统、线束开关和连接器等的技术创新起到推动作用。     

电动汽车用内置式永磁同步电机气隙磁场解析建模与多目标优化

为提高电动汽车用内置式永磁同步电机气隙磁场解析计算精度和优化效率，利用混合解析法建立考虑转子铁心磁桥饱和效应的电机气隙磁场参数化解析模型。首先利用联合等效磁路法的子域法建立内置式永磁同步电机开路气隙磁场解析模型；然后利用同样方法建立转子磁桥虚拟磁场解析模型，从而得到考虑转子磁桥饱和效应的电枢反应磁场解析模型；最后通过叠加原理建立内置式永磁同步电机合成气隙磁场解析模型。通过有限元仿真和转矩测试验证内置式永磁同步电机气隙磁场解析模型的准确性。基于所建立的解析模型，以永磁体极弧宽度、定子槽口宽度和转子端部磁桥厚度为优化变量，以特定阶次频率的径向力波、转矩和效率为优化目标，利用带精英策略的非支配排序遗传算法，对一台电动汽车用内置式永磁同步电机样机进行多变量多目标优化。研究结果表明：与试验结果相比，解析计算误差小于5%,而计算时间较有限元仿真缩短90%以上；优化后，电机特定阶次频率的径向力波减小了9.2%,最大转矩提升了2.49%,最大效率提升了0.69%,高效区面积扩大了约54.46%;所提方法既解决了内置式永磁同步电机强非线性和高饱和的解析建模共性难点，又极大提高了电机多目标优化效率；研究可...     

纯电动汽车动力系统故障分析

随着新能源汽车的发展,纯电动汽车的市场保有量愈来愈高,随着而来的新能源汽车后服市场也逐渐新起。纯电动汽车动力系统是纯电动汽车的核心部件,包括能源系统和驱动系统两个大的子系统。能源系统的主要组成部分为动力电池和动力电池管理系统。驱动系统的主要组成部分为驱动电机及电机控制器。文章归纳总结了动力系统的故障现象,对现象进行故障等级和故障类型的划分。并选取了三个典型案例进行故障排除,为维修人员提供参考。     

Experimental studies on the heating performance of the PTC heater and heat pump combined system in fuel cells and electric vehicles

In this study, a combined system consisting of a heat pump and a PTC heater was developed as a heating unit in electric vehicles. The system consists of a compressor, a condenser, an evaporator, an expansion device and a PTC heater. Experiments were conducted to examine the steady-state performance and dynamic characteristics of this system. The compressor speed, outdoor air inlet temperature, and indoor air inlet temperature were varied, and the performance of the system was experimentally investigated. The heating capacity, compressor power consumption and COP were obtained. Warm-up experiments were performed to investigate the dynamic characteristics of the system with a heat load of 1.5 kW in the indoor chamber. For the heat pump system, the PTC heater and the combined system, the heating performance and efficiency were investigated to determine an optimal control method. The results of this study agree well with the experimental results available in literature. This study provides experimental data of good quality for heating system design and the development of electric vehicles.     

Simple design approach for improving characteristics of interior permanent magnet synchronous motors for electric air-conditioner systems in HEV

In this paper, a simple design method for improving the performance of an interior permanent magnet synchronous motor (IPMSM), for driving the air-conditioning compressor used in hybrid electric vehicles, is presented. There are many design methods that optimize the IPMSM. Each method deals with a variety of design factors, such as slot opening, pole arc, and rotor shape. However, as the number of design variables increases, a lot of modeling and analysis time is needed in order to improve the characteristics of an IPMSM. This paper demonstrates that the optimization of a double-layer IPMSM, satisfying the given design conditions, is possible with only a flux barrier shape design. Then, response surface methodology is applied as the optimization method, and the validity of the design approach is verified by comparison with test results.     

单轴并联式混合动力总成的设计

设计完成了驱动电机与电控共轨柴油机结合而成的混合动力汽车动力总成,该总成用于单轴并联式混合动力汽车。驱动电机既是电驱动装置,又是起动、发电一体化系统(ISG),基于MC 68H9S12DP256B单片机,研制了该总成的控制系统,通过CAN总线实现了联合控制,以电池充放电平衡和发动机燃油经济性为基础,应用了一种模糊逻辑控制策略,实现了混合动力系统的扭矩分配与不同工作模式以及模式间的切换,该总成能够在所要求的工作模式下运转。     

机场专用清扫车的主要功能及其结构组成

传统的机场清扫车具有刷扫、吸拾、磁吸、吹除四大功能,广泛应用于机场跑道、滑行道、停机坪道面的机械化清扫作业,在文章中,讲解了一款新型动力系统的机场清扫车,采用“副发动机驱动液压泵+液压马达带动风机”的动力输出型式,在液压传动和电控系统中,传感器采集分机转速信号,控制器实时调节变量泵的排量,达到风机转速及功率根据需要自动调节,可实现风机的无极调速,传动平稳可靠,降低对副发动机的冲击,提高了整机车工作可靠性和使用寿命。     

PHEV发动机冷却系统优化设计

基于台架测试,对某款PHEV发动机的冷却系统不同水泵转速的流量分布,不同发动机负荷的热量分布,以及能量流进行研究,发现薄弱环节并进行优化设计,基于AMESim仿真平台进行建模及仿真预测.结果表明,通过优化乘员舱采暖回路控制以及取消无效流量回路,可以实现系统水阻降低2.8％,电子水泵功耗下降23％,暖风回路流量提高27％...     

新一代汽车电气系统——36/42V阀控式铅酸蓄电池

介绍新一代汽车电气系统对电池发展的影响,新型汽车电池的选择程序及36/42V电系的引入;阐述了该电系对电池制造商和汽车制造商所提出的要求。     

Torque ripple minimization control of permanent magnet synchronous motors for EPS applications

This paper identifies a control method used to reduce torque ripple of a permanent magnet synchronous motor (PMSM) for an electric power steering (EPS) system. NVH (Noise Vibration Harshness) is important for safe and convenient driving. Vibration caused by motor torque is a problem in column type EPS systems. Maintaining a very low torque ripple is one solution that allows for smoother steering. Theoretically, it is possible to design and drive the motor without torque ripple. However, in reality, a PMSM system torque ripple is caused by the motor itself (saturation in the iron core and EMF distortion) and the imperfect driver. This paper analyzes torque ripple of a PMSM system, and an advanced PMSM control method for the column typed EPS system is presented. Results of the analysis indicate that the compensation current is needed in order to minimize torque ripple when a PMSM is driven.     

汽车42V/14V直流转换器设计

利用SC51022芯片设计出42V/14V转换器,该转换器适用于42V电气系统的汽车,功率为100W,可对小型用电设备供电。     

Analysis of planetary gear hybrid powertrain system part 2: Output split system

In recent studies, various types of multi-mode electric variable transmissions for hybrid electric vehicles have been proposed. A multi-mode electric variable transmission consists of two or more different types of a planetary gear hybrid powertrain system (PGHP), which can change power flow type using clutches to improve transmission efficiency. Input split systems are generally used for the single-mode powertrain because of their overall superiority, but other power split systems such as output split and compound split systems can be used in the dual-mode powertrain. In this study, we analyze the power transmission characteristics of output split systems, and evaluate their fuel economies in the FTP72 cycle, acceleration performance, and constant vehicle speeds. These results enable the selection of appropriate systems for a dual-mode powertrain.