高压共轨柴油机电控系统设计

日趋苛刻的排放法规和能源危机成了内燃机行业关注的焦点,柴油机电控系统是柴油机的核心关键技术,为柴油发动机获得更好的排放指标、动力性能和经济性能提供了现实可行性,其中ECU（电子控制单元）的设计是实现柴油机控制的基础,决定着ECU总体框架、控制功能与驱动能力。随着柴油机总体对电控供电效率、     

国内重型柴油机0BD标准发展综述

本文首先回顾重型柴油机国内外OBD标准发展历程,根据中国重型柴油机国Ⅳ、国Ⅴ、国ⅥOBD的法规要求对标准内容、循环方式、型式检验进行对比研究。详细分析主机厂在不同阶段OBD开发的主流技术路线,目的是全面梳理中国重型柴油机OBD标准发展趋势,下一阶段OBD法规趋势为弱化发动机型式认证的要求,OBD直接监测车辆排放状况,实现主管部门达标监管的最终目的。增加整车OBD的型式认证内容,重点关注NOx控制系统功能验证,OBD相关部件的故障验证以及OBD相关功能验证,本文可以指导企业下一步OBD重点开发方向。     

矿山自卸车起动控制过程及故障研究

早期的矿山自卸车一般使用机械泵柴油机,随着人们对发动机排放及油耗要求越来越高,矿山自卸车逐步开始使用大缸径系列电控柴油机。为了了解大缸径电控柴油机的起动过程,以及帮助维修人员更方便的解决电控柴油机起动过程中遇到的故障,本文对大缸径柴油机的起动过程原理进行了详细介绍,并对常见起动困难故障原因进行分类、总结。同时,本文通过故障处理的实例,介绍了大缸径电控柴油机起动故障的处理过程,为维修人员解决此类故障提供了参考。     

基于虚拟仪器的柴油机电控系统试验监测平台设计

介绍应用NI公司LabVIEW虚拟仪器软件,设计搭建针对型号柴油机电控系统的试验监测平台。详细说明了在虚拟仪器开发环境下,利用串口通信技术,完成对柴油机电控系统各状态参数的在线监测。所研制的试验监测装置能够实时监测多台柴油机电控系统产品,并能对电控系统产品进行控制和试验数据记录,其中显示界面可以实时图形化显示多台电控系统主要运行参数及故障报警的情况,满足各种型号电控系统试验通用化要求,提高电控系统产品制造验收效率。     

船用柴油机电控高压共轨系统技术特点及管理

阐述了电控共轨柴油机的工作过程和特点,并与传统柴油机在性能和结构上进行了比较,在介绍电控柴油机优点的同时,对当前主流机型SulzerRT-flex和MAN-BWME-C的电控技术进行了对比和分析;探讨了船用柴油机电子喷射燃油系统的运行管理措施,指出电控共轨燃油喷射系统可改善船舶柴油机的经济性、可靠性和排放性,是船用柴油机的发展方向。     

电控柴油机的使用与维护

1.机电控单元（ECU）的使用注意事项 （1）柴油机出厂时已进行了严格的试验,用户不得随意调整ECU的数据以改变柴油机的功率和配置。 （2）整机电控系统的检修必须由专业人员进行。 （3）用户不得自行拆解ECU、共轨油泵和喷油器。进行焊接操作或插拔ECU的插接器时,务必切断ECU的电源,以防损坏ECU或其他部件。     

柴油机共轨限压阀打开故障的研究与分析

随着柴油机技术日趋成熟,高压共轨燃油系统柴油机被广泛应用,但当在某些条件被触发或者出现故障时,柴油机共轨限压阀会被打开,柴油机限制最高转速至1500rpm,即进入跛行回家模式,并限制柴油机扭矩输出,需要停车断电重启ECU后故障才能暂时恢复。针对该故障现象,从柴油机本体到与整车的匹配,以及机械方面、电气系统、电控数据等因素,进行了深入的分析和研究,对故障原因进行分类归纳、总结排查步骤和方法,从而为故障快速定位和解决提供依据。     

基于ET7190的发动机ECU监控系统设计

随着发动机电控系统功能的不断提升,传感器和执行器的数量也在不断增加,导致与电子部件相关故障的增加。为此,以OBD系统为基础,开发了一套选择通过CAN总线或K线读取ECU中的数据,显示各传感器和执行器的工作参数的系统,用来发现和判断发动机故障及其类型并报警提示。试验验证表明了监控系统的可行性。     

融合电控柴油机传感器数据的贝叶斯综合故障诊断网络研究

针对电控柴油机故障源多样性和不确定性的问题,对故障现象、状态数据提取及处理、贝叶斯故障诊断网络、故障源的先验概率获取、故障源的确定等方面进行了研究,在故障现象出现的情况下对如何有效确定故障源进行了分析和归纳,构建了融合传感器数据的电控柴油机贝叶斯网络综合故障诊断模型,提出了使用传感器数据技术检测电控柴油机工作状态,并结合经验法等估算出各类故障源的先验概率。通过运用贝叶斯网络技术推断查找到故障源的方法,并以丰田1KZ电控柴油发动机为实验对象,使用Hugin Expert工具对该诊断网络进行了推理验证。研究结果表明,该诊断网络充分发挥了传感器数据诊断技术的实时性和贝叶斯网络技术的判断决策能力,有效提高了电控柴油机故障诊断的正确率和实效性。     

DPF捕集效率故障诊断方法研究

随着全球排放法规的加严,柴油机对颗粒物排放的要求越来越高。目前,重型柴油机主要采用DPF(柴油机颗粒过滤器或颗粒捕集器)来减少排气中颗粒物排放。根据国六排放法规,柴油机后处理带有DPF时,必需对DPF捕集效率故障进行诊断。本文以采用BOSCH系统的某款重型柴油机为研究对象,通过分析颗粒物传感器和DPF压差传感器不同故障诊断策略,基于WHTC循环探究这两种诊断策略对DPF捕集效率故障判定的适用工况。研究发现,压差传感器法监测DPM捕集效率故障只适用于在高负荷工况与DPF堵塞故障监测及无故障车辆区分度较大的发动机,颗粒物传感器法测DPF捕集效率故障适用于绝大多数工况。     

数控加工中心自动换刀系统的研究

自动换刀系统( ATC)包括刀库机构、换刀机构以及控制系统3个部分,是加工中心的重要组件之一.为了解决数控加工中心自动换刀速度慢、稳定性低及控制系统编程复杂等问题,将一种软件式内置PLC技术应用于自动换刀系统中.在分析自动换刀系统的基本结构、工作原理以及研究圆盘刀臂式自动换刀系统的控制流程的基础上,结合ServoWor...     

基于大脑皮层互信息理论的睡眠分级研究

睡眠的分级研究是睡眠状况分析和睡眠质量评价的前提和基本内容。目前国际通用的睡眠分级方法，是利用脑电信号另加脑功能信号（如肌电图、眼动电流图），且必须由人工判别分析。大脑皮层互信息理论是研究脑功能变化的有力工具。通过动脉计算睡眠脑电4个导联之间的互信息时间序列的复杂度，并利用一个3层的的人工神经网络进行6个级别的分类。6例720个不同时期的睡眠片段的测试表明，系统睡眠分级与人工分级的总相符率达到90.83%，且实现了睡眠动态自动分级。神经网络的学习功能，可使系统的准确率进一步提高，逐渐接近或达到人工分级的水平。与其他睡眠分级方法相比，本系统有一定优势，且计算速度快，可望应用于临床实时睡眠监护及睡眠分析中。     

Effect of the molecular weight on deformation states of the polystyrene film by AFM single scanning

Nanobundles patterns can be formed on the surface of most thermoplastic polymers when the atomic force microscope (AFM)‐based nanomechanical machining method is employed to scratch their surfaces. Such patterns are reviewed as three‐dimensional sine‐wave structures. In the present study, the single‐line scratch test is used firstly to study different removal states of the polystyrene (PS) polymer with different molecular weights (MWs). Effects of the scratching direction and the scratching velocity on deformation of the PS film and the state of the removed materials are also investigated. Single‐wear box test is then employed to study the possibility of forming bundle structures on PS films with different MWs. The experimental results show that the state between the tip and the sample plays a key role in the nano machining process. If the contact radius between the AFM tip and the polymer surface is larger than the chain end‐to‐end distance, it is designated as the “cutting” state that means the area of both side ridges is less than the area of the groove and materials are removed. If the contact radius is less than the chain end‐to‐end distance, it is designated as the “plowing” state that means the area of both side ridges is larger than the area of the groove and no materials are removed at all. For the perfect bundles formation on the PS film, the plowing state is ideal condition for the larger MW polymers because of the chains’ entanglement. SCANNING 35:308‐315, 2013. © 2012 Wiley Periodicals, Inc.     

四轴数控电解加工整体叶轮阴极轨迹计算及速度处理

在阐述用直纹面拟合扭曲型面的基础上,用刚体变换的方法推算出阴极的控制轨迹。首次提出求取段指令周期的迭代算法,可保证加工过程中阴极对型面的法向速度有最小的变化率,为进上步提高展成电解加工的精度提供了理论依据。实验证明,该证明,该方法虽然加工时间略有加长,但精度却有明显改善。     

一次进样分析氩气中碳、硫化物和质量数丰度值与比值

建立了一次进样分析氩气中的碳、硫化物信号和质量数丰度值与比值的方法,并可获知单位氩气内不同质量数的分子、原子分布20,Ar≈3.28%;36 Ar≈0.17%;37 Ar≈0.09%;40 Ar≈62.6%;41 Ar≈33.84%;42 Ar≈0.02%。     

Applying the min-projection strategy to improve the transient performance of the three-phase grid-connected inverter

Applying the min-projection strategy (MPS) to a three-phase grid-connected inverter to improve its transient performance is the main objective of this paper. For this purpose, the inverter is first modeled as a switched linear system. Then, the feasibility of the MPS technique is investigated and the stability criterion is derived. Hereafter, the fundamental equations of the MPS for the control of the inverter are obtained. The proposed scheme is simulated in PSCAD/EMTDC environment. The validity of the MPS approach is confirmed by comparing the obtained results with those of VOC method. The results demonstrate that the proposed method despite its simplicity provides an excellent transient performance, fully decoupled control of active and reactive powers, acceptable THD level and a reasonable switching frequency.     

An object-oriented reference model of the fuzzy front end of the new product introduction process

The global pressures of the modern market are placing an ever-increasing emphasis on the rapid development and introduction of new products. Central to this aim is the implementation of an effective business process for managing and controlling product innovation. Research has shown that the front end stages of the so-called new product introduction (NPI) process are weakest in a high proportion of companies and direct support is needed in this area. This paper describes how an object-oriented methodology has been applied to develop a reference model and architecture to facilitate the re-engineering and implementation of a high quality business process and help remove the fuzziness of the critical early stages of NPI. The results from the application and testing of this tool within a wide range of different companies are summarised and used to help derive conclusions regarding the validity of the research.     

Assessment of the sulfide stress corrosion cracking characteristics in the multi-pass weld of the A106 Gr B steel pipe

Sulfide stress corrosion cracking (SSCC) in crude oil field environment containing hydrogen sulfide (H₂S) has been recognized as a material degradation and damage mechanism. Laboratory data and field experience have demonstrated that extremely low concentration of H₂S may be sufficient to lead to SSCC failure of susceptible materials. In some cases, sulfides may act synergistically with chlorides to produce SSCC failures. SSCC mechanism is a form of hydrogen embrittlement that occurs in high strength steels and in localized hard zones in weld of susceptible materials. In the heat-affected zones adjacent to the weld, there are often very narrow hard zones combined with regions of high residual stress that may become embrittled to such an extent by dissolved atomic hydrogen. On the basis of this understanding, SSCC tests were conducted with smooth specimens of the multi-pass welded ASTM A106 Gr B steel pipe used in the oil industries. And SSCC resistance according to the welding processes was evaluated. From the results, the weld by GTAW+FCAW showed the largest resistance against SSCC. This paper was recommended for publication in revised form by Associate Editor Chongdu Cho Gyuyoung Lee received the M.S. degree in Mechanical Engineering from Sungkyunkwan University in 2003 and 2005, respectively. Currently he is in doctorate course in Sungkyunkwan University. He is currently serving as a Reliability member of the Korean Society of Mechanical Engineers. Lee’s research interests are in the area of welding design, environmental strength of materials, and life prediction and reliability assessment of the industrial facilities.     

带冠整体叶轮加工现状及新方法探索

综述了带冠整体叶轮的特点及国内外研制工作的现状，针对现有工艺方法的不足，提出了一种新的加工方法，即电解加工与电火花加工的组合电加工方法，进而对该工艺方法进行了介绍，分析了其技术特点。通过试验，其可行性得到了验证，有望成为带冠整体叶轮叶片型面的一种有效加工方法。     

IEC62443系列标灌概述韧SAL介绍

本文描述了IEC62443系列标准框架的发展过程，系列标准的主要内容和信息安全保证等级的定义，类型以及基本要求。