Parameters optimum matching of pure electric vehicle dual-mode coupling drive system

As an important development direction of pure electric vehicle drive system, the distributed drive system has the advantages of compact structure, high transmission efficiency, and flexible control, but there are some serious problems such as high performance requirements to the drive motors, complex control strategies, and poor reliability. To solve these problems, a two motors dual-mode coupling drive system has been developed at first, which not only has the capacity of two-speed gear shifting, but also can automatically switch between the distributed drive and the centralized drive by means of modes change control. So, the performance requirements to the drive motors can be reduced, the problem of abnormal running caused by the fault of unilateral distributed drive systems also can be resolved by replacing the drive mode with centralized drive. Then, the system parameters primary and the optimum matching under the principle of efficiency optimization have been carried out, which makes the drive system achieve predetermined functions and meet the actual demands of different operating statuses. At last, the economic comparison of a pure electric vehicle installation with a dual-mode coupling drive system, a single-motor centralized drive system or a dual-motor distributed drive system in the simulation conditions has been completed. Compared with other systems, the driving range of the electric vehicle driven by the designed system is significantly increased, which proves the better efficiency and application value of the system.     

Rollover prevention control for a four in-wheel motors drive electric vehicle on an uneven road

When a four in-wheel motors drive electric vehicle with a specific wheels mass is running on an uneven road and transient steering occurs in the meantime, the joint action of the large unsprung dynamic load and the centrifugal force may cause the vehicle to rollover. To avoid the above accident, a rollover prevention control method based on active distribution of the in-wheel motors driving torques is investigated. First, the rollover evolution process of the four in-wheel motors drive electric vehicle under the described operating condition is analyzed. Next, a multiple degrees of freedom vehicle dynamics model including an uneven road tyre model is established, and the rollover warning threshold is determined according to the load transfer ratio. Then, the hypothesis of the effects of unsprung mass on the vehicle roll stability on a plat road and on an uneven road is verified respectively. Finally, a rollover prevention controller is designed based on the distribution of the four wheels driving torques with sliding mode control, and the control effect is verified by simulations. The conclusion shows that, once the wheels mass does not match road conditions, the large unsprung mass may play a detrimental role on the vehicle roll stability on an uneven road, which is different from the beneficial role of large unsprung mass on the vehicle roll stability on a plat road. With the aforementioned rollover prevention controller, the vehicle rollover, which is caused by the coupling effect between large unsprung dynamic load and suspension potential energy on an uneven road, can be avoided effectively.     

Powertrain design and energy management of a novel coaxial series-parallel plug-in hybrid electric vehicle

For a series plug-in hybrid electric vehicle,higher working efficiency can be achieved by the drive system with two small motors in parallel than that with one big motor alone.However,the overly complex structure will inevitably lead to a substantial increase in the development cost.To improve the system price-performance ratio,a new kind of series-parallel hybrid system evolved from the series plug-in hybrid system is designed.According to the technical parameters of the selected components,the system model is established,and the vehicle dynamic property and pure electric drive economy are evaluated.Based on the dynamic programming,the energy management strategy for the drive system under the city driving cycle is developed,and the superiority validation of the system is completed.For the studied vehicle driven by the designed series-parallel plug-in hybrid system,compared with the one driven by the described series plug-in hybrid system,the dynamic property is significantly improved because of the multi-power coupling,and the fuel consumption is reduced by 11.4%with 10 city driving cycles.In a word,with the flexible configuration of the designed hybrid system and the optimized control strategy of the energy management,the vehicle performance can be obviously improved.     

四轮独立驱动轮毂电机电动汽车研究综述

基于轮毂电机驱动的电动汽车是未来汽车的重要发展方向,而针对四轮独立驱动轮毂电机电动汽车的发展和国内外研究现状,论文进行了综述。首先介绍了轮毂电机和轮毂电机电动汽车结构和控制特点,对四轮独立驱动轮毂电机电动汽车国内外研究概况进行了说明,最后指出从产品化角度四轮毂电机电动汽车在稳定性控制、城市工况节能控制方面进行深入的理论研究和实践探索,而充分发挥其控制优势进行基于驾驶员特性的智能控制是未来研究的重要内容。     

Optimum Driving System Design for Dual-Motor Pure Electric Vehicles

A pure electric vehicle driven by dual motors is taken as the research object and the driving scheme of the driving motor is improved to increase the transmission efficiency of existing electric vehicles. Based on the architecture of the transmission system, we propose vehicle performance parameters and performance indexes of a pure electric vehicle, a time-sharing driving strategy of dual motors. First, the parameters of the battery, motor, and transmission system are matched. Then, the electric vehicle transmission model is built in Amesim and the control strategy is designed in Simulink. With the optimization goal of improving the vehicle’s dynamic performance and driving range, the optimal parameters are determined through analysis. Finally, the characteristics of the motor are tested on the bench. The results show that the energy-saving potential of the time-sharing driven double motor is higher, and the driving mileage of the double motor drive is increased by 4%.     

基于MSP430F449的自动寻迹电动小车

介绍了电子竞赛使用的具有自动寻迹行驶功能电动小车的设计与实现方法.本设计以MSP430F449为核心,利用自制传感器识别黑色引导线,MSP430F449控制集成H桥芯片驱动两个带减速机构的小直流电机,小直流电机分别驱动左右车轮沿黑色引导线行驶.     

Research on Hybrid Input Mechanical Press Driven by Two Motors

1 Introduction The mechanical press is very important for plastic forming, whose service performance has a direct effect on the quality of workpieces and the working life of dies. The transmission system of a general mechanical press consists of a belt drive, gear reducer and crank-slider mechanism. This transmis- sion system gives the slider a higher speed at the de- formation stage of the plastic workpiece and clearly has some heavy disadvantages. Cracks easily initiate on the bottom of a cy…     

电动汽车电气驱动系统

针对电动汽车对驱动系统的基本要求，对其驱动电机及电力电子器件特性进行了分析和比较，就电动汽车电气驱动系统中驱动电机的应用、电力电子器件的发展趋势及器件的选用准则提出了一些建议。     

双驱轮毂式电机在无人驾驶中的控制与仿真

针对无人驾驶车在直行和转弯过程中轮毂式驱动电机输出转速不协调的问题,将电子差速控制策略引入车辆控制系统中．根据速度矢量对控制系统的影响,设计了以永磁无刷直流电机控制技术为基础的电子差速控制器．该系统以无人驾驶车需要的车速和转弯角度为输入,两后驱电机转速为输出．对驱动电机转速与时间的响应曲线进行了仿真,仿真结果表明此控制器完全能够实现机械差速器的功能,可以实现车辆直线行驶和转弯过程中车轮自由差速．     

混合动力技术在军用汽车上的应用

以BJ212军用轻型越野车为例,对其改为混合动力后的驱动型式、动力总成参数的确定以及性能预测等方面进行了初步探讨。结果表明,改变后的越野车易于实现纯电动行驶和停车发电的功能,更能适应野战部队的需要。与原车相比,最高车速提高30%,最大爬坡度提高34%,油耗降低30%,同时能在纯电动模式下以50km/h的速度行驶33.7km。     

基于车辆循环工况并联混合动力汽车感应电机额定功率和效率的匹配

提出了基于车辆循环行驶工况并联混合动力汽车感应电机额定功率的匹配方法,在电机过载能力范围内根据每个循环工况电机的需求功率确定常用功率区域和额定功率。给出了基于工况匹配电机本体效率的计算方法。结合北京、伦敦循环工况,与解放牌混合动力客车的第二轮样车40kW电机进行对比仿真分析,结果表明,基于工况匹配的电机进一步提高了整车燃油经济性。     

State Estimation of the Electric Drive Articulated Dump Truck Based on UKF

The requirements of vehicle dynamic stability control are higher than ever as the significant increase of electric drive articulated vehicle speed. According to the construction features of articulated dumping truck and nonlinear characteristics of moving vehicles, nonlinear observer of vehicle status is designed to strength robustness of dynamic control system in this paper. A 4-degree-of-freedom nonlinear dynamic model of articulated electric drive vehicle is built as reference model to estimate the state of the articulated vehicle. And by adopting Unscented Kalman Filter (UKF) algorithm, a series of state parameters such as longitudinal velocities of front and rear frames, yaw rate and side-slip angle are estimated. During the test of 60 t articulated electric drive vehicle, 2 inertial navigation modules are installed in the front frame and rear frame respectively and the speed of each electric drive wheel is obtained simultaneously. As the test results suggest, in various working conditions, the algorithm based on UKF is able to accurately estimate the state parameters of articulated vehicle with the estimated error less than 5%. The proposed method is justified to be the theoretical basis and application guidance for articulated vehicle stability control.     

Simulation of Steering Performance for Electric Drive Tracked Vehicle

According to the analysis of the fundamental steering theories of the electric drive tracked vehicle, a new effective electric drive tracked vehicle model is built in this paper. And the simulation of the steering performance of the vehicle is made. The results show that the electric transmission has great advantage on the steering performance aspect; the small radius steering and even the pivot steering is realizable, and the agility and the rapidness is wonderful. The regenerative energy can be fully utilized by controlling.     

分布式独立驱动车辆复合转向匹配特性研究

为研究分布式独立电驱动车辆的复合转向机理,提升车辆的转向机动性、操纵稳定性,以某型8 × 8独立电驱动车辆为对象,构建整车仿真模型、分布式独立电驱动控制模型以及车辆复合转向控制模型,在几何转向的基础上,通过在驱动轮主动叠加速差转角即前馈施加车轮虚拟偏转角的方法,分析在相同轮转角状态下,几何转向模式与复合转向模式对车辆转向半径的影响。通过不同行驶工况下的动态仿真,结合车辆的横摆角度、侧向加速度、质心侧偏角等车辆稳定性特性参数,分析复合转向对于车辆操纵稳定的影响,得出分布式独立电驱动车辆复合转向匹配特性。     

Simulation investigation of tractive energy conservation for a cornering rear-wheel-independent-drive electric vehicle through torque vectoring

Although electric vehicle fully exhibits its comparative merits of energy conservation and environmental friendliness, further improvement of its traction energy efficiency lacks comprehensive investigations in the past. In this paper, the effect of the torque vectoring on traction energy conservation during cornering for a rear-wheel-independent-drive electric vehicle is investigated. Firstly, turning resistance coefficient and energy conservation mechanism of torque vectoring are derived from the single track dynamic model. Next, an optimal torque vectoring control strategy based on genetic algorithm is proposed, with the consideration of the influence of the operation-point change of the in-wheel motors, to find out the best torque vectoring ratio offline. Finally, various simulation tests are conducted to validate the energy conservation effect after Simulink modelling. The results verify that though the optimization of the operating region of the motors is the main part for tractive energy conservation, the contribution of torque vectoring itself can reach up to 1.7% in some typical cases.     

基于双伺服电机的电动助力转向器硬件在环仿真试验平台

针对传统汽车转向系统建模仿真方法精度不高的问题,在深入研究二自由度整车动力学模型和轮胎模型的基础上,设计开发了一套基于双伺服电机加载的电动助力转向器（EPS）硬件在环仿真试验平台.EPS总成输入端可以选择方向盘手动加载或伺服电机自动加载,输出端则根据整车动力学模型和轮胎模型在当前方向盘转角及实车运行参数下的求解结果,由输出端伺服电机动态模拟实际汽车转向阻力矩,并通过检测关键信号指导调试与检验EPS系统性能.实际应用表明,该试验平台实时性、可靠性好,仿真试验精度高,能对EPS关键性能参数进行准确把握,非常适合于EPS系统的研发、测试及性能评价.     

四轮独立驱动电动车转向驱动的转矩协调控制

通过对四轮独立驱动电动汽车进行转矩协调控制进行动力学理论分析,表明转矩协调控制可以增强车辆的动力性以及弯道极限行驶性能,提高车辆的操纵性和稳定性。提出采用BP神经网络PID控制方法协调驱动力矩。利用建立的四轮独立驱动电动车7自由度模型进行了阶跃输入、稳态回转和正弦输入仿真。仿真结果表明:提出的转矩协调方法改善了车辆的操纵性和稳定性。     

电力测功机动态测试平台系统

为了测试电动汽车电机驱动性能,开发了一台高性能电力测功机测试系统,该系统使用他励直流发电机负载电机和可工作在4个象限的高性能控制器,实现了电机转速的闭环控制,配备了高性能的转矩传感器和全数字化的数据采集系统,实现了对异步电机、直流电机、永磁无刷电机、永磁同步电机及相应控制器的动、静态性能测试．     

辅助混合动力电动汽车技术研究(Ⅱ)--驱动电机控制系统及关键技术

针对辅助混合动力电动汽车的运行特点,完成了基于单片机80C196KC的电动汽车驱动控制系统的设计,介绍了系统设计中的关键技术与调试经验,在输入信号的处理与IGBT的驱动保护方面做了深入研究．实验结果表明,系统整体性能优良,实现了对驱动电机的安全可靠控制．     

电动汽车盘式轮毂永磁电机设计

为了合理地设计盘式轮毂永磁电机,利用盘式永磁电机对电动汽车轮毂进行了研究.在对电动汽车特性要求以及电机结构、材料、特点分析的基础上,选用盘式无铁芯永磁同步电机作为电动汽车轮毂直驱电机.为选择理想的电机参数,通过理论分析的方法对轮毂式电动汽车总体动力性能进行分析计算,讨论了决定轮毂电机选择的电动汽车3项主要性能指标：最高车速、加速时间与最大爬坡度.根据电动汽车的性能要求,最终合理地确定了轮毂电动机的功率、转速与转矩,给定了轮毂电动机的主要参数,为轮毂盘式电机的设计提供了依据.