【作者】 马英；

【导师】 邓兆祥；

【作者基本信息】 重庆大学 ， 车辆工程， 2013， 博士

【摘要】 电动汽车作为唯一能达到零排放的机动车越来越受到人们的欢迎，电动车轮也称为电动轮技术作为电动汽车的一个重要的发展方向，特别是由外转子轮毂电机直接驱动车轮行驶的电动车轮，将动力传递机构最大程度的进行了简化，动力得到了高效的传递；将整车的动力系统转移到车轮空间内，大大提高了车内可利用空间；永磁同步电机技术的发展为电动车轮车辆提供了高功率密度的轮毂电机；通过线控技术对电动车轮内电机的控制，可以使车轮对控制的响应更为迅速，也为实现四轮独立控制策略提供了更多的可能。但是将整车动力系统从车身移至车轮内，不仅存在轮内结构布置空间紧张的问题，而且动力系统的安装使车轮部分质量增加，车身与车轮的质量比降低，将造成车辆平顺性降低、车轮动载荷变大、道路友好性和行车安全性降低等车辆垂向负效应问题，这也正是当前电动车轮驱动车辆研究需要解决的关键问题。为了实现电动车轮内驱动、制动、传动及连接装置在电动车轮内合理布置，有效利用轮内空间，设计出能够驱动车辆高速、稳定、安全且轻量化的电动车轮，本文结合电动车轮驱动的电动车辆悬架构型的分析，深入的研究了电动车轮结构。分析轮毂电机不同安装方式得到的电动车轮车辆动力学构型，证明了轮内悬浮电机是解决电动车轮驱动车辆垂向振动恶化问题的最佳动力学构型。研究轮毂电机质量增加对车辆平顺性造成的影响，系统的分析并对比由电动车轮不同安装方式得到的车辆悬架构型及其动力学微分方程。根据轮毂电机作为动力吸振器，对整车起减振作用时受到轮内空间限制这一实际情况，提出相对车轮的垂向运动量作为不同悬架构型参数优化的约束条件，得到将轮毂电机和制动器在车轮内悬浮的电动车轮最优的悬架构型，并通过对比验证：本文优化计算得到的采用最优构型的电动车轮车辆不仅可以解决轮毂电机引入造成的簧下负效应问题，而且可以得到比原车的更优的平顺性和安全性。提出基于最优控制算法的轮内主动减振系统来减小电机和车轮之间相对位移。综合考虑轮毂内部空间限制、车辆行驶工况变化以及车身簧上簧下质量比不固定等因素，发现在有限的轮内空间中，轮毂电机所占空间与其相对车轮垂向运动位移相互制约，本文又以保持车辆的平顺性性能不降低为基本要求，以减小轮毂电机相对车轮的垂向位移为目标，对轮内主动减振系统进行了研究，目的是降低电动车轮内结构对空间的要求。经过验证：电动车轮在主动减振系统的作用下，不仅保证了车辆的平顺性，而且大大降低了减振过程中轮毂电机相对车轮的位移，即降低了轮内减振系统结构对轮内空间的要求，另外因主动减振系统结构简便可以减小轮内减振系统所占空间，并可以通过控制算法的调整适应电机、车轮及车身质量变化，避免因刚度、阻尼设计需求变化造成减振系统结构重新设计匹配。发明了一种新型高速电动车轮。根据最佳动力学构型将轮内电机由簧下质量转化为轮内动力吸振器来提高车辆平顺性的原理，采用弹簧阻尼机构将环形电机和制动器悬浮在车轮内，采用十字滑块传动装置实现电机与轮毂间的等速传动，解决了轮内悬浮电机的结构实现问题，满足高速行驶要求的同时，改善整车平顺性和操稳性。根据电动车轮车辆对轮毂电机的需求和对不同特点电机的比较，确定外转子永磁同步电机作为电动车轮驱动电机，并根据汽车理论计算与车辆动力型匹配的电机性能，采用场路结合的方法分析了轮毂电机关键参数，通过对电机进行仿真分析和试验台验证，电机的转矩和转速满足车辆的动力性需求。对电动车轮的轻量化设计从三个方面进行了研究，首先利用电机设计分析软件，经过分析和对比优化出满足车辆动力性，质量减小9kg的轮毂电机电磁方案；然后根据现有电机壳体、制动盘和传动机构结构有限元分析结果，采用铝合金材料来对电机壳体和传动机构进行重新设计，可使质量降低约23kg；最后又通过对轮内减振系统的弹簧、导向杆和液压阻尼减振器集成一体化的碟片弹簧液压减振装置，在提高车辆平顺性的同时减轻了电动车轮质量。更多还原

【Abstract】 Electric vehicle becomes more and more popular because that it is the only kind ofvehicle which creates no pollution. As an important developing aspect of electric cars,the electric wheel especially which is driven directly by external rotor in-wheel motor,can extensively simplify the power transmission system, making power transmissionwith a high efficiency. The electric car’s power system lies in the wheels, providingmore inner space available for users. Meanwhile, the permanent magnet synchronousmotor can provide in-wheel motor with high power-density. Through the wire control tothe in-wheel motor, the wheels response quicker to the control, providing moreprobabilities to achieve independent control policy for the wheels. However, moving thepower system from the body to the wheels brings a problem to the placement in thewheel; further more, the wheel mass will increase, the mass ratio of the body to wheelwill decrease by the mounting of power system, thus decreasing the car smoothness,increasing dynamic load of wheels, decreasing road friendly and driving security,causing vertical negative effect problems to the car. Above are the key problems thatneed to be solved by in wheel motor driven cars today. Involving with the analysis onsuspension structure of in-wheel motor driven car, this study gives a deep research onin-wheel motor’s structure, in order to place the driven system, braking system,transmission system and connection system right in the wheel, make full use ofin-wheel space, design electric wheels that can drive the car speedily, stably, safely andlightly.The in-wheel motor driven car’s kinetic structure elicited by analyzing differentmounting modes of in-wheel motor proves that the suspension motor in the wheel is theoptimized kinetic structure, which can solve the exacerbating problem of verticalvibration. In this essay, we studies the affection to the smoothness caused by the massincrease of in-wheel motor, systematically analyze and compare the vehicle suspensionstructure and its kinetics differential equation by different mounting modes of theelectric wheel. Applying the in-wheel motor as the vibration absorber will be limited inthe spaces of the wheel in a damping action. In this situation, we put the verticalmovement as an restriction to optimize parameters of different suspension structures,work out the optimized suspension structure of electric wheel where the in-wheel motorand arrester are suspended to the axis. We conclud after comparison that electric car with optimized structure can not only solve the negtive unsprung affection of thein-wheel motor, but also obtain smoothness and safty better than the one without thatoptimized structure.In-wheel initiative damping system basing on optimized control algorithm canreduce the relative displacement between the motor and the wheel. Taking the spacelimit of the wheel, driving road differences, and the unfixed ratio of body’ssprung/unsprung mass into account, we found that the space required by in-wheel motorwould interact with the vertical relative displacement of the wheel in limited space.Meanwhile, this essay uses keeping the vehicle smoothness as basic condition, reducingthe vertical relative displacement between in-wheel motor and the wheel as the target,studies on the in-wheel initiative damping system, for reducing the space requirement ofthe in-wheel motor. By way of simulation, this study validates that in-wheel initiativedamping system can not only insure the smoothness, but also greatly reduce the relativedisplacement between the in-wheel motor and the wheel during shock absorption, whichmeans reducing the space requirement of the damping system. In addition, the initiativedamping system can reduce the space requirement; also can avoid the re-design matchof the damping system structure by way of adapting changes of the motor, wheel andbody mass through a controller.This study introduces a new high speed electric wheel. Based on the theory thattransforming in-wheel motor’s unsprung mass to vibration absorber will improve thesmoothness according to optimized kinetic structure, we use a sprung damper tosuspend the annular motor and the arrester in the wheel, and a crisscross slidertransmission system to achieve the transmission between the motor and wheel at aneven speed. In this way, we can resolve the problem of the suspension motor structure inthe wheel, meeting the demand of a high driving speed, improving the smoothness andstability at the same time. By comparing different motors according to the claim of theelectric vehicle to in-wheel motor, we fix on the external rotor permanent magnetsynchronous motor as the motor of electric wheels. Also, according to the calculationabout the motor performance matching the vehicle’s kinetic performance, we analyzethe key parameters of in-wheel motor through the method of field circuit combination.By the simulation analysis and test-bed validation, we conclude that the torque andspeed of the motor can meet the requirement of vehicle’s kinetics performance.The lightness design of electric wheel is researched from below three aspects.Firstly, shape the electromagnetism scenario of in-wheel motor with a9kg mass reduce which satisfies the vehicle kinetics performance by using the motor design and analyzesoftware; secondly, based on the Finite Element Analysis result about the structure ofmotor shell, brake disc and transmission system, redesign the motor shell andtransmission system with aluminum alloy material, reducing the mass by23kg alike;thirdly, by integrating disc spring hydraulic damping device with the sprung of thedamping system, oriented pole and hydraulic damper, improving smoothness andreducing wheel mass at one time.更多还原