某型纯电动轿车动力系统参数匹配与优化

以某款纯电动轿车为研究对象,根据其动力性与经济性设计指标,提出一种基于NEDC行驶工况的参数设计方法,对该车的电动机和动力电池进行了选型与参数匹配。为了在满足动力性指标的基础上进一步提升经济性,针对变速器和主减速器参数提出一种基于自适应模拟退火算法的多目标优化方案,利用权重法将表征汽车动力性的多目标优化问题转化为单目标优化问题,得到综合动力性优化目标函数,并将一次NEDC工况总能耗作为经济性优化目标函数,再基于自适应模拟退火算法得到多目标优化问题所需的最优解。仿真结果表明优化后车辆的综合性能有较好提升。     

无级变速传动系统整体优化控制策略

传统的发动机最佳经济性和最佳动力性控制策略不能保证传动系统整体性能最优。以无级变速传动系统整体性能最优为目标,从经济性、动力性和瞬态工况特性三个方面论述基于功率需求的整体优化控制策略。制定发动机、液力变矩器和无级变速器的整体效率优化算法,求解最佳节气门开度控制表、最佳速比控制表和液力变矩器理想闭锁控制线。在经济性模式下,以满足功率需求的整体最高效率点作为控制目标;在动力性模式下,根据功率需求计算目标节气门开度,以当前车速下的整体最大功率点的速比作为目标速比。在瞬态工况下,直接以车辆有效驱动功率作为控制目标,结合发动机转矩补偿与速比变化率限制,给出恒功率和零功率两种量化控制模式。仿真结果表明,整体优化控制策略使经济性提高3.2%,40～80 km.h–1的超车加速时间缩短13.7%,避免急加速过程中的动力疲软现象。     

复合储能式装载机能量控制优化与仿真

针对工程车辆在机群作业下的能量管理问题,以复合储能式装载机为研究对象,利用Recurdyn-Edem联合仿真建立连续作业环境获取工况数据;分别以V型工况及集群作业下装载机单次循环工况油耗最少为目标,设计了基于等效油耗最小策略与规则相结合的控制策略,为了能够进一步提高全局工况的燃油经济性,使用遗传算法对等效油耗最小关键参数进行寻优,最后带入整车模型进行仿真验证。结果表明,V型工况与集群作业工况下,该控制策略相较于自适应神经模糊控制,燃油经济性分别提升了3.23%和4.26%;通过dSPACE进行硬件在环试验,试验与仿真结果基本一致,进而验证了优化结果的有效性。     

双状态无级变速传动系统整体效率优化

针对现有无级变速传动系统效率优化算法的不完整性,以整体效率最优为目标设计最佳工况点求解算法,制定基于功率需求的传动系统整体优化控制策略,将满足功率需求的最高效率点作为基本控制目标,以实现最佳经济性;当功率需求超出传动系统功率范围时,将当前车速下的最大输出功率点作为控制目标,以实现最佳动力性;求解液力变矩器理想状态切换线,制定实际切换控制线。试验验证和对比分析结果表明,采用优化控制策略降低油耗近3%,起步加速时的变矩器闭锁时间缩短11%,最大输出功率提高2.3%。     

基于动态规划的液力机械自动变速传动(HMPRT)自动换档控制策略

针对外界负载变化比较剧烈的轮式装载机等工程车辆采用传统液力机械自动变速器时,面临着效率偏低、油耗较大的问题,提出在轮式装载机上应用新型回流式液力机械自动变速传动(Hydraulicmechanicalpowerrefluxtransmission,HMPRT)系统。装载机需要通过换档来适应复杂的作业要求,所以结合HMPRT调速特性制定基本换档规律。考虑到装载机等工程车辆常在已知典型的工况下进行作业,同时为避免基本换档规律的动力性和经济性模式的来回切换,降低驾驶员的工作量,采用动态规划建立HMPRT换档规律的优化设计方法。该方法首先根据装载机常用作业工况的特点及HMPRT的换档特性,确定DP控制参数,以燃油消耗作为代价函数,并且增加惩罚函数,用来避免产生频繁换档现象。研究结果表明,采用动态规划提出的换档规律时,与最佳动力性换档规律相比燃油消耗降低3.5%,与最佳经济性换档规律相比换档次数减少33.3%。综合考虑了典型作业工况,在保证动力性和经济性的同时,避免了频繁换档。     

两挡纯电动汽车传动系换挡规律及速比优化研究

以提高电动汽车动力性与经济性为目标,对两挡纯电动汽车传动系速比进行优化设计。以0~80 km/h加速时间和ECE-EUDC-LOW循环工况百公里耗电量分别作为电动汽车动力性与经济性的两个分目标函数,建立了双目标函数下的速比优化模型。考虑到换挡规律在速比优化过程中的耦合效应,确定了与速比关联的兼顾动力性与经济性的换挡规律制定准则。设计一种具有非支配比较筛选功能的枚举算法,求取双目标函数的Pareto最优解集。结果表明,相对于初始速比,电动汽车采用某组优化速比时加速时间缩短了3.5%,百公里耗电量降低了2.4%,电动汽车动力性与经济性得到了提高。     

AMT经济性换挡研究

挡位决策就是根据车辆运行情况、道路情况和驾驶员的意图,按照某些目标(如动力性、经济性)最优的原则确定当前车辆的挡位,并通过选换挡执行机构控制变速箱换挡。     

基于智能控制的装载机自动换挡策略

装载机具有工况复杂的特点,提出根据驾驶意图采用多种换挡规律相结合的装载机自动换挡控制策略,并将模糊逻辑应用于司机驾驶意图的识别。对ZL50G型装载机进行改装,构建自动变速控制系统,进行整机现场铲掘和行走试验,结果表明,该自动换挡策略的控制逻辑正确,简化了驾驶员操作。V形铲掘作业和行走工况的油耗数据表明,采用该自动换挡策略在降低换挡劳动强度的同时起到节约能源的作用,兼顾装载机工作的经济性、动力性和实用性。     

装载机发动机输出功率分配特性的试验研究

装载机发动机功率分配特性研究有利于发动机多功率工作模式的设计与应用。以某典型装载机为例,在计算其传动轴转矩、转速基础上,结合液压系统工作压力,选择并标定了转矩与液压传感器,将转矩、转速与液压传感器信号接入数据采集仪,构建了装载机参数测试系统,应用n Soft软件、采用"铲-续-铲"方式对实车测试数据进行处理,获得了典型工况下装载机传动系统与液压系统实时动态消耗发动机功率历程谱图,针对谱图中反映出的同一工作循环不同作业段消耗发动机功率相差较大情况,提出将发动机功率设计为高、中、低三种功率工作模式,在满足实际作业需要的同时达到节能降耗的目的。     

基于粒子群算法的电动汽车常用工况的两挡变速器速比优化

针对电动汽车多挡变速器速比优化过程中,仅对单一特定工况进行优化,而与实际工况相差较多的不足,提出了基于粒子群算法的传动系常用运行区效率最优的速比优化方法,即通过多种特定工况的叠加找出电动汽车常用运行区,并通过调节速比的方式使电动汽车传动系的高效区最大可能地落入常用运行区内,使传动系平均运行效率最高。以整车动力性为约束条件,以电动汽车传动系常用运行区域下平均效率为经济目标,整车加速时间为动力性目标构建适应度函数,利用Matlab软件编写程序实现速比优化,并用AMESim软件搭建整车模型进行整车能耗验证。结果显示,通过优化后整车动力性经济性均有提升,表明所用的方法有效。     

基于CAD模型的齿轮辐板优化设计

对一种基于二维CAD模型的齿轮辐板优化设计方法进行了研究.探讨了其优化数学模型的建立方法,包括设计变量的选择、目标函数的确定及约束条件的选取.讨论了模型的数据结构及有关参数的计算,开发了齿轮辐板优化设计通用计算程序.并对某直升机减速器中的一薄辐齿轮辐板进行了优化,有效地减轻了齿轮的重量,取得了良好的效果.     

FOUR-PARAMETER AUTOMATIC TRANSMISSION TECHNOLOGY FOR CONSTRUCTION VEHICLE BASED ON ELMAN RECURSIVE NEURAL NETWORK

From the viewpoint of energy saving and improving transmission efficiency, the ZL50E wheel loader is taken as the study object. And the system model is analyzed based on the transmission system of the construction vehicle. A new four-parameter shift schedule is presented, which can keep the torque converter working in the high efficiency area. The control algorithm based on the Elman recursive neural network is applied, and four-parameter control system is developed which is based on industrial computer. The system is used to collect data accurately and control 4D180 power-shift gearbox of ZL50E wheel loader shift timely. An experiment is done on automatic transmission test-bed, and the result indicates that the control system could reliably and safely work and improve the efficiency of hydraulic torque converter. Four-parameter shift strategy that takes into account the power consuming of the working pump has important operating significance and reflects the actual working status of construction vehicle.     

NGWN(Ⅱ)型行星减速器基于Matlab的优化设计

针对NGWN(Ⅱ)型行星齿轮减速器提出了侧重于配齿计算、啮合及几何参数计算等的专用设计软件,建立了以减速器体积最小为目标,以齿轮强度要求等为主要约束条件的优化设计模型,并进行了基于Matlab的优化设计,获得了理想的、具备工程实用价值的综合设计效果.     

装载机智能减阻铲装控制策略及实验研究

为了降低装载机铲装作业时因轮胎滑转而造成的功率损失,提出了一种以破坏物料致密性为基础的智能减阻铲装控制策略.基于理论分析明确了装载机铲装时的作业阻力形成机理,确立了通过自动提升动臂来破坏密实核以达到减阻插入的新思路.提出了基于现有液压系统的改进方案,并设计了基于轮速差值的装载机智能减阻铲装控制策略.后续铲装实验证明,该...     

大功率轮胎式装载机的液压传动系统研究

通过对装载机静压传动和动压传动两种传动方式的比较 ,分析了静压传动系统相对于采用液力机械的动压传动的一些优点 ,指出装载机发展现状及开始向高技术、大型化、采用静压传动的趋势。在分析装载机大型化和采用静压传动存在的问题的基础上 ,提出了大功率轮胎式装载机的静压传动方案。     

Modeling,validation and energy flow analysis of a wheel loader

This paper presents a wheel loader simulation model, validation results and energy flow analysis. The developed simulation model will facilitate the performance evaluation and optimization process in the development stage of a prototype wheel loader. The wheel loader simulation model consists of mechanical and hydraulic powertrain model, multi-body dynamic model and working part dynamic model. The multi-body dynamic model is simplified since the effect of pitch and roll motion of the wheel loader on the energy flow of the powertrain and hydraulic actuator systems is insignificant, a simplified planar model for the dynamic vehicle is good enough for the objective of this study. Every component is modeled and integrated in a simulation package developed using Matlab/Simulink. The simulation model has been validated using experiment data and the validation results show that it effectively represents the actual dynamic characteristic of the target wheel loader. The verified simulation model will be used as a virtual platform to evaluate the performance of alternative powertrain models such as a dual-clutch transmission and hydrostatic transmission. An advanced control system can also be implemented and evaluated using the virtual platform.     

新型液压拼焊工艺装备的设计与应用

阐述了装载机结构件新型液压拼焊工艺装备的有关原理和发展趋势，并通过对比现有的结构件拼焊工艺装备常用的夹紧模式，较为详细地剖析了设计装载机结构件液压拼焊工艺装备的思路，成功实现了在装载机三大结构件上的应用。确保了结构件的拼焊质量，提高了工作效率，降低了工人的劳动强度。     

Optimization of hydro-mechanical power split transmissions

The increasing attention to comfort, automation and drivability is pushing the driveline technology to ever complex solutions, such as power-shift or continuously variable transmissions. Between these, the hydro-mechanical solution seems promising for heavy duty vehicle, due to the reliability and the capability of transferring high power. However, the double energy conversion occurring in the hydraulic branch of the transmission could lower excessively the total efficiency, highlighting the needs for a careful design of the whole system.In this work, the design of a hydro-mechanical transmission is defined as an optimization problem in which the objective function is the average efficiency of transmission, while the design variables are the displacements of the two hydraulic machines and gear ratios of ordinary and planetary gears. The optimization problem is solved by a “direct search” algorithm based on the swarm method, which showed a good speed convergence and the ability to overcome local minima.The optimization design method will be applied to study the transmission of two vehicles: a 62 kW compact loader and a high power agricultural tractor.     

基于自混合干涉的齿轮箱故障诊断技术

将激光自混合干涉（SMI）技术用于齿轮箱的故障检测,设计出一种新的齿轮箱故障检测传感器。采用QL65D5SA型半导体激光自混合传感器、冯哈勃2342l012CR空心杯减速电机自带的行星齿轮箱,搭建了行星齿轮箱故障SMI检测系统,并对行星轮Z1做断齿故障实验。通过对时域波形的分析,可以找到额定转频下的12个冲击点;通过对齿轮箱故障信号傅里叶频谱的分析,发现故障齿轮的啮合频率周围出现与故障齿轮特征频率和行星架转频呈整数倍关系的边带,且啮合频率处的波形幅值明显增大,这些都与齿轮副的理论振动模型相符合。     

Adaptive state detection of gearboxes under varying load conditions based on parametric modelling

Conventional vibration monitoring techniques are unable to provide accurate state analysis of a gearbox under varying load condition. This paper proposes a novel technique for state detection of gearbox, which fits a time-varying autoregressive model to the gear motion residual signals applying a noise-adaptive Kalman filter, in the healthy state of the target gear. The optimum autoregressive model order, which provides a compromised model fitting for the healthy gear motion residual signals collected under various load conditions, is determined with the aid of a specific model order selection method proposed in this study. Consequently, a robust statistical measure, which takes the percentage of outliers exceeding the three standard deviation limits is applied to evaluate the state of the target gear, where the standard deviation of autoregressive model residuals takes its maximum in all tested gear motion residual signals for model order selection. The proposed technique is validated using full lifetime vibration data of gearboxes operating from new to failure under four distinct load conditions. The investigated load conditions include: (1) constant load, (2) one jump from 100 to 200% nominal torque level, (3) one jump from 100 to 300% nominal torque level, and (4) constant changed to sinusoidal. In each application, the specific model order selection and comparison of the proposed gear state indicator with three counterparts proposed in recent studies are addressed in detail. The Kolmogorov–Smirnov test is also performed as a complementary statistical analysis. The results show that the proposed technique possesses a highly effective and robust property in the state detection of gearbox, which is independent of varying load condition as well as remarkable stability, early alarm for incipient fault and significant presence of fault effects. The proposed gear state indicator can be directly employed by an on-line maintenance program as a reliable quantitative covariate to schedule optimal maintenance decision for rotating machinery.