硕士学位毕业论文 硕士研究生： 贾振铎 指导教师：沈斌 教授 答辩时间：2014.06 摘要 电动汽车作为新能源汽车，因其采用清洁能源、无尾气排放、低噪音、电动机效率高、结构简单等特点已成为各汽车厂商重点研发的对象，电动巴士是新型环保的交通工具，对缓解城市环境压力具有重要意义。由于电动汽车驱动与传动原理均不同于传统汽车，因此其自动变速器的设计要适应电动汽车自身的特点进行，液压系统是自动变速器的控制中枢，它可控制自动变速器换档，并为自动变速器的传动系统提供冷却润滑油液。本文为电动巴士的三档自动变速器设计一套液压系统，并对该液压系统进行整体三维建模，然后利用多学科 CAE 仿真软件 ITI SimulationX 对液压系统进行动态特性仿真。论文研究的主要内容如下： 1 ．阐述论文研究背景及意义，分析国内外自动变速器液压系统发展与研究现状。 2 ． 根据 电动汽车自动变速器的设计要求，在分析电动汽车三档自动变速器工作原理的基础上，通过动力分析和运动分析，确定了液压系统主要参数，绘制了液压系统工作原理图，完成了液压系统功能原理设计和结构设计。 3 ．设计了液压系统各功能部件。选择液压泵的类型为摆线泵，根据液压系统油液流量、压力等参数，对摆线泵进行了结构设计，应用 KISSsoft 软件对摆线泵主轴进行强度校核。利用 计算软件 MathCAD 建立限压阀、安全阀和润滑系统节流孔的数学模型，设计并优化了以上元件和结构的几何参数。 设计液压控制阀块，合理布置集成于阀块上的元件。设计阀块、自动变速器箱体及自动变速器前后端盖上的油路。 结合液压系统设计要求与实际需要，选择液压系统的电磁阀、 骨架油封、 O 型圈、传感器等元件。利用 KISSsoft 软件设计计算液压系统所有螺栓、螺钉。在完成液压系统设计方案的基础上，应用 3D 建模软件 Creo Parametric 2.0 对液压系统进行整体三维建模。 4 ．利用仿真软件 ITI SimulationX 建立了三档自动变速器液压系统仿真模型，在油温为 30 0 C、6 0 0 C、9 0 0 C和12 0 0 C 时，对液压系统油液压力、流量等参数进行动态特性仿真，通过对仿真结果的分析，验证了液压系统设计方案的可行性，并对具体设计进行了改进。 关键词： 自动变速器，液压系统，设计，仿真， SimulationX ABSTRACT Electric autos are new energy autos. Because of clean energy, no exhaust emissions, low noise, high efficiency motors, simple structure and other characteristics, they have become the focus of research and design of the automotive manufacturers. Electric buses are an environmentally friendly way of transport. They are a paragon of alleviating the pressure on the urban environment. Because the driving principle of electric autos differs from conventional autos, the automatic transmission of an electric auto is designed to adapt to the characteristics of electric autos themselves. The hydraulic system is the control center of an automatic transmission. It is able to control the shift of an automatic transmission and provide lubricating fluid to cool and lubricate the drive system of an automatic transmission. A hydraulic system for a 3-gear automatic transmission of an electric bus has been designed and was built into 3D models by using the software Creo Parametric 2.0. Based on the multi domain CAE simulation software ITI SimulatonX, the hydraulic system of the automatic transmission was modeled and simulated. The main contents of the research of this thesis are as follows: 1. The technical characteristics and development trend of electric autos and automatic transmissions have been analyzed, the significance of the development of an automatic transmission has been explained. The above mentioned studies laid the foundation for the later research. 2. The design requirements of automatic transmissions have been clarified. The schematic diagram for the working principle of the hydraulic system was designed based on the analysis of the working principle of the 3-gear automatic transmission of the electric bus. The main parameters of the hydraulic system have been determined, the function and structure design of the hydraulic system have been accomplished. 3. The components of the hydraulic system has been designed. Gerotor pump has been selected as the model of the hydraulic pump. It has been designed according to the flow and pressure of the fluid and other parameters of the hydraulic system. The intensity of the principal axis of the pump was then assessed by using the software KISSsoft. The key parameters of the relief valve, the safety valve and the orifices of the lubrication system are calculated and optimized based on the calculation software MathCAD. The hydraulic control valve block of the hydraulic system has been designed with a reasonable arrangement of the elements, which were integrated into the valve block. The oilway of the hydraulic control valve block, the transmission case, the front and rear cover of the transmission have been designed. Three solenoid valves, an oil seal, an O-ring, two temperature sensors and two pressure sensors were designed according to the combination of the design requirements for the hydraulic system and the actual needs. All the bolts and screws in the hydraulic system were calculated and designed by using the software KISSsoft. The hydraulic system was built into 3D models by using the software Creo Parametric 2.0 on the basis of the overall design of the hydraulic system. 4. The simulation model of the hydraulic system was built based on the simulation software ITI SimulatonX and was simulated in an oil temperature of 30 0 C、6 0 0 C、9 0 0 C和12 0 0 C . The dynamic flow and pressure of the fluid and other parameters for the hydraulic system, have been analyzed based on the results of the simulation. According to the above analysis, the design of the hydraulic system was optimized and its feasibility was verified. Key words: automatic transmission, hydraulic system, design, simulation, SimulationX
硕士学位毕业论文 硕士研究生： 任莎莎 指导教师：沈斌 教授 答辩时间：2012.06 摘要 随着汽车工业的发展，汽车市场竞争日趋激烈，各大汽车生产厂为了争取更 多的客户、更大的市场，都围绕改善汽车驾驶的舒适性、节能、环保等方向进行不懈的研究。 汽车电动助力转向 (EPS) 系统是近年来发展起来的一种新型动力转向系统，具有节能、质量轻、安全、环保等一系列优点，正逐步取代传统的液压助力转向系统，成为动力转向系统发展的一个主流趋势，EPS不仅能够改善汽车驾驶舒适性、节能、环保，同时对降低生产和维护成本、缩短开发周期、减少开发成本等多个方面都大有裨益。因此，发展 EPS 成为当今汽车生产商、零部件开发商以及科研机构的研究热点。并且随着计算机技术的迅速发展，多体动力学软件 MSC.ADAMS 的开发，为EPS系统的研究提供了更为方便有效的平台。 本研究着重进行了以下几项工作： 首先， 详细分析了EPS的系统结构和工作原理及其主要的组成部件，并分析了EPS转向系统在工作过程中的受力情况 , 建立了 EPS 转向系统的动力学方程。 其次，对EPS的关键技术助力特性进行了详细的分析和研究，给出了直线型，折线型和曲线型三种助力特性的数学方程，并分析了三种助力特性的优劣。其后根据曲线型助力特性的数学模型和助力特点，提出了基于 BP 神经网络优化算法计算任意车速下方向盘转矩与电机助力转矩的非线性关系的方法。对基于 BP 神经网络优化算法的EPS系统控制策略和算法进行了深入研究 , 通过分析车辆和驾驶员对转向控制的要求和特点 , 获得了汽车车速和方向盘扭矩二输入下的EPS的助力特性 。 其后， 基于车辆动力学的建模方法 , 利用 MSC.ADAMS/CAR 软件 建立了 EPS 转向系统仿真模型 , 以及用于整车动力学分析的整车模型 。 最后，基于 ADAMS 的 整车模型，进行 典型工况下的整车仿真分析 ，通过对有无 EPS 的横摆角速度和侧向加速度等参数的对比 说明了 EPS 系统对提高汽车操纵稳定性方面有一定的积极作用。 关键词 ： 电动助力转向，助力特性， ADAMS ，仿真 ABSTRACT With the development of the automotive industry, the competition is fiercely in the auto market. In order to get more customers and bigger market, all the vehicle companies are doing their best to improve comfortable of driving, energy saving, environmental protection etc. and direction of unremitting study. Electric power steering system (EPS) is a new power steering system developed in recent years. With a number of advantages of energy saving, light weight, safety, environmental protection etc., EPS is gradually replacing the traditional hydraulic power steering and has become a major trend in the development of the power steering system. EPS is not only to improve comfortable of driving, decrease consume energy, prevent the pollution of the environment, but also can reduce production and maintenance costs, shorten the development cycles, reduce development costs and other aspects of a great benefits. Therefore, the development of EPS becomes one of the hottest topics what automobile manufacturers, parts developers and research institutions focus on. With the rapid development of computer technology, the multi-body dynamics software of MSC.ADAMS provides a more convenient and effective platform for the study of EPS. This research focuses on the following aspects: First of all, a detailed analysis of systematic constructer, the working principle and great compenent, and force analysis of EPS steering system in the course of its work, set up EPS steering system dynamics equation. Secondly, a detailed analysis and research of power assist characteristic, which is is the key technology of EPS, gave three mathematical equations for a straight line, polyline type and curve type of power assist characteristics, and analyzed the advantages and disadvantages of the three power characteristics. Subsequently, according to curve type of mathematical models and assist characteristics, based on BP neural network, brought forward to calculate the nonlinear relationship between the steering wheel torque and motor power assist torque at any the speed of vehicle. EPS system control strategy and algorithm optimization algorithm based on BP neural network has conducted in-depth research, according to analysis of steering control requirements and characteristics of vehicle and driver, obtained the power assist characteristic of EPS under the two input of the vehicle speed and steering wheel torque. Secondly, based on vehicle dynamics modeling method, using the software of MSC.ADAMS/CAR, established the EPS system model, and the vehicle model for dynamic simulation analysis. Finally, based on ADAMS vehicle model, have done the vehicle dynamic simulation analysis under the typical conditions. Compared with the yaw rate and lateral acceleration parameters of vehicle between no EPS and with EPS systems illustrate that EPS have some active role to improve vehicle handling and stability. Key words : Electric power steering, Power assist characteristic, ADAMS/CAR; Simulation
标签: 仿真
