Extended-Kalman-filter-based regenerative and friction blended braking control for electric vehicle equipped with axle motor considering damping and elastic properties of electric powertrain

Because of the damping and elastic properties of an electrified powertrain, the regenerative brake of an electric vehicle (EV) is very different from a conventional friction brake with respect to the system dynamics. The flexibility of an electric drivetrain would have a negative effect on the blended brake control performance. In this study, models of the powertrain system of an electric car equipped with an axle motor are developed. Based on these models, the transfer characteristics of the motor torque in the driveline and its effect on blended braking control performance are analysed. To further enhance a vehicle's brake performance and energy efficiency, blended braking control algorithms with compensation for the powertrain flexibility are proposed using an extended Kalman filter. These algorithms are simulated under normal deceleration braking. The results show that the brake performance and blended braking control accuracy of the vehicle are significantly enhanced by the newly proposed algorithms.     

电子驻车制动卡钳电控性能测试系统的设计与实现

介绍了基于飞思卡尔MC9S12XS128MAL单片机的电子驻车制动卡钳电控性能测试系统,具体阐述了电子驻车制动卡钳无液压夹紧释放功能、有液压夹紧释放功能、电机过载性和电机欠电性测试的实现方法.该测试系统采用完全不同于汽车行业现有团体标准规定的试验方法,以更接近实车工况的方式进行测试,测试方法和测试系统具有一定的创新性....     

新能源电机系统性能匹配优化研究

主要针对新能源电机系统在不同车型上的应用进行性能匹配优化研究。从平台化的车型参数出发进行电机系统参数匹配优化设计,同时进行闭环仿真计算保证车辆的动力性能。在电机系统的效率优化提升方面,基于乘用车常用NEDC工况,获取电机系统在工况下的运行数据,基于仿真数据一方面研究电机系统在对应工况下的高效区间分布;另一方面根据电机系统在驱动和发电状态下的电功率和机械功率计算平均效率,同时结合不同方案下的效率MAP差异,判断不同方案在整车经济性上的表现。通过本文提到的性能匹配优化研究方法,可以缩短开发产品周期,保证项目在前期的输入定位相对准确,从而保证产品开发完成后可以有较强的市场竞争力,可以满足绝大多数车型的需求。更加有利于后续的市场推广。     

A locomotive–track coupled vertical dynamics model with gear transmissions

A gear transmission system is a key element in a locomotive for the transmission of traction or braking forces between the motor and the wheel–rail interface. Its dynamic performance has a direct effect on the operational reliability of the locomotive and its components. This paper proposes a comprehensive locomotive–track coupled vertical dynamics model, in which the locomotive is driven by axle-hung motors. In this coupled dynamics model, the dynamic interactions between the gear transmission system and the other components, e.g. motor and wheelset, are considered based on the detailed analysis of its structural properties and working mechanism. Thus, the mechanical transmission system for power delivery from the motor to the wheelset via gear transmission is coupled with a traditional locomotive–track dynamics system via the wheel–rail contact interface and the gear mesh interface. This developed dynamics model enables investigations of the dynamic performance of the entire dynamics system under the excitations from the wheel–rail contact interface and/or the gear mesh interface. Dynamic interactions are demonstrated by numerical simulations using this dynamics model. The results indicate that both of the excitations from the wheel–rail contact interface and the gear mesh interface have a significant effect on the dynamic responses of the components in this coupled dynamics system.     

Development of dry hybrid belt CVT

We have developed a continuously variable transmission (CVT) which has superior transfer efficiency, by thoroughly reducing transfer loss by means of using a dry hybrid belt, using no lubrication composition system around the belt, and using an electric control system of a DC motor.The fuel efficiency and driveability of the prototype vehicle equiped with the CVT were proven equivalent or even superior to a 5 speed manual transmission.     

基于功能安全的分布式驱动电动汽车前轮失效补偿控制

分布式驱动电动汽车可以实现四轮转矩分配和差动转向,提升整车的动力学控制性能和经济性,但是四轮转矩独立可控的特点也对功能安全提出挑战。当前轮单侧电机出现执行器故障失效情况时,不仅会产生附加横摆力矩降低车辆安全性,差动转向功能的存在还会使车辆严重偏航。基于此,在设计分布式驱动-线控转向一体化底盘的基础上,基于功能安全提出一种分布式驱动电动汽车前轮失效补偿控制策略。首先建立分布式驱动失效动力学模型,分析前轮失效对车辆状态的影响机理,发现单一的驱动转矩截断控制无法满足车辆状态修正需求;其次设计一套备用的线控转向结构,通过变截距滑模控制算法提高切换状态下线控转向系统的转角跟踪性能,并用台架试验验证跟踪的准确性;然后设计自适应失效诊断观测器实时诊断驱动系统的电机故障,在将对应轮进行驱动转矩截断后,通过模型预测控制算法对车轮转矩重新分配实现纵向和侧向的状态跟踪;最后通过仿真和实车试验验证所提失效补偿控制策略的有效性和可用性。研究结果表明：分布式驱动电动汽车前轮单侧电机失效后,备用的线控转向系统能及时矫正前轮转角,所提出的失效补偿控制策略能够快速恢复车辆的稳定性和路径跟踪能力。     

汽车通用电动机性能测试系统

从系统的组成、功能、参数测试方法、负载转矩的施加等方面，介绍了所研制的通用型汽车电动机性能测试系统，并着重对归算到标准电源电压和标准环境温度的校正方法进行了深入的探讨。最后给出了应用实例。     

现代汽车车载自诊断系统效率的分析

现代汽车车载自诊断(OBD)系统存在一个OBD不能监测出故障(误诊)的区域，该区域定义为自诊断系统的“盲区”。产生自诊断盲区时，汽车使用性能开始下降。汽车OBD系统产生的盲区主要受电子连接及布线技术、汽车传感器质量和执行器性能、汽车接地技术等凶素的影响。     

Development of capacitor hybrid truck

Nissan Diesel Motor has developed a capacitor hybrid medium-duty truck. This vehicle involves a new power-train technology which makes for high efficiency and low emission with the basic technology being a high performance capacitor type storage device. The newly developed capacitor has an energy density that is twice as great as commercial ultracapacitors. The simple parallel hybrid system of this vehicle was composed of this capacitor, a single motor, a conventional diesel engine and a mechanical automatic transmission system. Fuel economy about 1.5 times greater than that of a conventional diesel truck is achieved. Furthermore, the TLEV level of exhaust emissions is also achieved.     

电动汽车驱动控制策略研究综述

驱动系统是电动汽车研制的关键技术之一,它直接决定电动汽车的性能。矢量控制通过坐标变换将定子电流矢量分解为转子磁场定向的两个直流分量并分别加以控制,从而实现异步电动机磁通和转矩的解耦控制,达到直流电动机的控制效果。直接转矩控制,并不需要观测转子磁链,它基于定子磁场控制磁场定向以转距作为被控量,思路清晰,手段直接。本文根据电动机矢量控制及直接转矩控制理论,结合电动汽车的实际要求,对其的现状及优缺点进行了分析及说明,介绍了改进的控制措施及发展趋势。     

Shape design optimization of interior permanent magnet motor for vibration mitigation using level set method

This paper presents a new optimization method to obtain the structural design of permanent magnet motor which can reduce the mechanical vibration. The optimization problem is formulated to minimize a multi-objective function including the mean compliance of the whole stator for maximizing the stiffness under the magnetic force and the torque ripple by aligning torque profiles to a constant target value for maximizing the magnetic performance, with constraint for material usage. The level set function is introduced for representing the structural boundaries and calculating the material properties. A coupled magneto-mechanical analysis is performed to verify the vibration characteristic of the motor system and obtain the design sensitivities. To confirm the usefulness of the proposed design method and to obtain the optimum structural design for low vibration motor, a design example of 20 kW interior permanent magnet motor developed for the power train of a hybrid electric vehicle is provided.     

18000 r/min超高转速轻量化新能源汽车电机轴开发

随着新能源汽车电机转速的不断提升,电机轴面临更加苛刻的刚强度、耐久性和抗过挠要求。通过合理选材,并辅之以轻量化设计、磁环境优化、工艺匹配等方法,成功开发出满足18 000 r/min服役要求的电机轴。新电机轴在质量减少25.5%时,其自由模态频率、扭转强度、扭转疲劳寿命、台架试验过程中的噪声和温升等性能指标均不低于原低转速电机轴。通过对材料成分及工艺的优化以增强基体的强韧性有利于提升电机轴的抗扭及抗疲劳性能。通过轻量化结构设计和反向辅助磁场设计,可降低电机轴在高速旋转过程中承受的单边磁拉力、离心力、系统重力等,也有利于提升电机轴的抗挠能力,进而提升电机的耐久性和车辆的舒适性。     

电传动矿用自卸车轮边电机驱动系统动态特性研究

矿区环境复杂,电传动矿用汽车的轮边电机传动系统对整车动力性、制动性及平顺性有极大影响,为了综合路面激励和电机自身激励综合分析驱动系统动态特性,采用数值仿真软件建立轮边电机传动系统模型,分析其在启动加速、平稳运行及制动时的动态特性,为了验证模型的准确性进行了实车实验。结果表明该轮边电机传动系统的输出转矩发生考虑波动转矩后会较大影响整车加速和制动性能,常见车速的加速和减速性能会减弱5%,稳定行驶阶段差别不大。刚柔耦合模型能更准确地描述驱动系统及整车动力特性,对整车的设计有指导意义。     

纯电动汽车动力驱动系统电动机的选择方法之研究

本文首先介绍了电动汽车用电动机的基本性能,并从汽车行驶动力学出发建立了纯电动汽车用电动机性能参数的数学模型,其次探讨总结了对电动机基本特性参数的初步确定原则。最后以目前所要开发的一辆纯电动汽车的基本参数及目标性能要求为例,按以上原则确定出电动机参数并绘制符合要求的电动机性能曲线,为电动机的快速选择和后续车辆动力传动系统匹配优化提供了依据。     

Improvement of drivability and fuel economy with a hybrid antiskid braking system in hybrid electric vehicles

When braking on wet roads, Antilock Braking System (ABS) control can be triggered because the available brake torque is not sufficient. When the ABS system is active, for a hybrid electric vehicle, the regenerative brake is switched off to safeguard the normal ABS function. When the ABS control is terminated, it would be favorable to reactivate the regenerative brake. However, recurring cycles from ABS to motor regenerative braking could occur. This condition is felt to be unpleasant by the driver and has adverse effects on driving stability. In this paper, a novel hybrid antiskid braking system using fuzzy logic is proposed for a hybrid electric vehicle that has a regenerative braking system operatively connected to an electric traction motor and a separate hydraulic braking system. This control strategy and the method for coordination between regenerative and hydraulic braking are developed. The motor regenerative braking controller is designed. Control of regenerative and hydraulic braking force distribution is investigated. The simulation and experimental results show that vehicle braking performance and fuel economy can be improved and the proposed control strategy and method are effective and robust.     

丰田FCHV-4型燃料电池汽车的结构特性分析

丰田汽车公司开发的FCHV-4型采用燃料电池和辅助电池作为混合动力系统的能源,极大提高能源转换效率,使汽车具有良好的性能。燃料电池与牵引电机逆变器直接相连,与辅助电池和DC/DC器串联。该燃料电池汽车的效率为传统内燃机汽车的3倍。     

Robust control system for continuously variable belt transmission

The continuously variable transmission control system consists of generation of a desired gear ratio and a servo gear ratio system. The servo gear ratio system must provide the desired response at all times without being influenced by external disturbances. These include oil pressure as well as variation in performance due to operating conditions or changes in control system characteristics with use. We have developed the servo gear ratio system incorporating a robust model matching method, which enables the continuously variable belt transmission to satisfy this performance requirement.     

双绕组永磁同步电机的设计及在客车上的应用

综合客车整车的动力性和经济性,再结合电机热平衡管理和冗余设计理念,研发了一种大功率大扭矩高效双绕组永磁同步电机。通过精准设计双绕组电机定转子结构,实现电机双源输出。扭矩叠加,整车动力性大幅提升,同时形成转矩耦合高效区,拓宽电机整体高效区占比,降低整车能耗,提高整车经济性。通过优化控制策略,实现电机两套绕组的分时驱动,确保电机温升和损耗始终处于较低状态,并保障了整车动力的不间断运行。     

一种电动汽车轮毂电机再生制动试验台架的设计与实现

设计了一种电动汽车用轮毂电机试验台,该试验台可将电机的性能测试试验与再生制动试验合二为一。介绍了该试验台的组成结构和测控系统工作原理,提出了电机再生制动试验方法及试验数据的计算公式,并利用虚拟仪器技术开发了测控系统软件环境。通过试验台的实际运行,验证了其台架设计的合理性及其测控系统控制方式的可行性。     

基于ADVISOR的电动汽车传动系统参数设计与性能仿真

对电动汽车电动机、传动系的传动比和电池组容量等参数设计的原则和方法进行了研究,以某种型号电动汽车为研究对象,对其动力传动系的参数进行合理的选择和设计.建立了整车动力传动系统的仿真模型,应用电动汽车仿真软件ADVISOR对整车动力性进行了仿真计算.仿真结果表明,以铅酸电池为能源的电动汽车的加速性、爬坡能力、最大车速、续驶...