国产化聚酯分散型控制系统的设计

介绍了江苏仪征化纤股份有限公司涤纶一厂国产化聚酯生产中分散型控制系统的组成结构,软硬件的设计和实施。重点介绍了DCS的全局操作站、局域控制网、高性能过程控制器、网络接口模件的组成结构。

适用于变电站的CAN现场总线通信适配卡的设计

在基于现场总线的变电站综合自动化系统中,各个节点之间的通信以及节点与上位机之间的通信是系统的核心;适配卡把节点的数据上传到上位机,同时又把上位机的命令和数据下传到节点,是核心中的关键。本文提出一种新的适配卡设计方案,采用ISA接口,使用89C 52微处理器,SJA 1000作为通信控制器,并利用双口RAM作为PC机与控制器之间的数据交换通道,使用EPLD器件作为双口RAM的控制和中断信号处理。最后简要阐述了适配卡的软件设计。

双丝高速软开关脉冲MAG焊装备

将CAN(局域控制网)总线技术、软开关技术、脉冲焊技术等有机地结合,研制了结构紧凑、一体化、协同控制的TANDEM型双丝焊装备。在深入分析双丝焊工艺要求的基础上,引入新型双闭环控制模式,实现了适合双丝焊要求的脉冲焊电源动特性、外特性。为减少双丝焊电弧之间的干扰,将CAN总线技术成功应用于双丝焊装备的通信控制中,设计了双丝焊装备的协同控制装置。结果表明,电源各项电气性能都满足了设计要求,且焊接过程稳定、飞溅小、焊缝成形好、焊接速度快、热输入小、变形小,突出显示了双丝高速焊的优点。

精密压力测试仪

针对洗衣机用水位传感器质量检测中存在的问题,开发了基于CAN(Controller Area Network)总线的精密压力检测系统。在上位计算机与前端测控模块之间的通信中,采用现场总线CAN网络技术。由于实现了系统冗余,系统具有安全可靠、功能完善、操作简便、性能价格比高等优点,成功实现了洗衣机用水位传感器检测的自动化,取得了较好的经济效益。

精密水位传感器测试仪

介绍了基于CAN(Controller Area Network)总线的精密水位传感器检测系统。在上位计算机与前端测控模块之间的通信中,采用现场总线CAN网络技术,系统不仅具有基本的参数测控功能,还可进行集中监控、参数设置、数据管理、报表打印等操作。由于实现了精确定位以及冗余,系统具有安全可靠、功能完善、性能价格比高等优点,成功实现了洗衣机用水位传感器参数的自动精确测量,取得了较好的经济效益。

精密水位传感器测试系统研制

针对洗衣机用水位传感器质量检测中存在的问题,开发了基于CAN(Controller Area Network)总线的精密水位传感器检测系统。在上位计算机与前端测控模块之间的通信中,采用现场总线CAN网络技术。由于实现了系统冗余,系统具有安全可靠、功能完善、操作简便、性能价格比高等优点,成功实现了洗衣机用水位传感器检测的自动化,取得了较好的经济效益。

新型工业循环冷却水自动加药系统

针对工业循环冷却水的处理问题,开发了基于CAN总线的工业循环冷却水处理系统。在上位计算机与前端测控模块之间的通信中,使用现场总线CAN网络技术。由于实现了系统冗余,系统具有安全可靠、功能完善、操作简便、性能价格比高等优点,大大提高了工业循环冷却水处理的自动化水平并取得了较好的经济效益。

精密水位传感器测试系统

本文针对洗衣机用水位传感器质量检测中存在的问题,开发了基于CAN(Controller Area Network)总线的精密水位传感器检测系统。在上位计算机与前端测控模块之间的通信中,采用现场总线CAN网络技术。由于实现了系统冗余,系统具有安全可靠、功能完善、操作简便、性能价格比高等优点,成功实现了洗衣机用水位传感器检测的自动化,取得了较好的经济效益。

油田深井智能通井仪监控系统设计与实现

该文具体研究了油田深井智能通井仪监控系统组成结构、地面和井下系统通信协议组成、基于高速混合单片机井下测控微系统的软硬件设计,同时简要介绍了现场总线CAN的特点和应用。该监控系统是对传统电动通井系统的技术改造与升级,适用于各种工艺措施造成堵塞的注水井、各种添加剂和工作液造成损害性堵塞的注水井、因温度、压力、PH值及矿化度等热力学条件的变化而形成的乳化堵、无机盐堵的注水井及井内析出高分子形成的有机物质堵塞的注水井。

Computer Network Control System in Automatic Automobile Detection

An automobile test controlling and managing system with computer network is introduced. The architecture of the local network, hardware structure, software structure, design of the test process, and error tolerating redundant design in work position substituting are presented. At last, the pivotal questions solved are discussed. With an advanced structure, this system is multi functional and flexible. Furthermore, advanced computer technology is adopted to improve its technical degree.

景洪水电站金属结构安装测量综述

本文介绍了云南景洪水电站金属结构安装工程测量控制过程,重点阐述表孔弧形门控制测量,支铰、底槛及检修门侧轨、弧门侧轨等施工安装测量及验收测量的难点、重点、解决方法及精度分析。

变电站现场总线适配卡设计分析

本文提出一种新的适配卡设计方案,采用ISA接口,使用89C52微处理器,SJA1000作为通信控制器,并利用双口RAM作为PC机与控制器之间的数据交换通道,使用EPLD器件作为双口RAM的控制和中断信号处理。最后简要阐述了适配卡的软件设计。

景洪水电站金属结构安装测量综述

本文介绍了云南景洪水电站金属结构安装工程测量控制过程,阐述了孔弧形门控制测量的方法,并对测量放样的实施过程中支铰、底坎及检修门侧轨、弧门侧轨等施工安装测量及验收测量的难点、重点、解决方法及精度进行了分析,提出获得精确度较高的测量成果的方法。

AN MAC PROTOCOL SUPPORTING MULTIPLE TRAFFIC OVER MOBILE AD HOC NETWORKS

This letter presents the design and performance of a multi-channel MAC protocol that supports multiple traffics for IEEE 802.11 mobile ad-hoc networks. The dynamic channel selection scheme by receiver decision is implemented and the number of the data channel is independent of the network topology. The priority for real-time traffic is assured by the proposed adaptive back off algorithm and different IFS. The protocol is evaluated by simulation and the results have shown that it can support multiple traffics and the performance is better than the performance that IEEE 802.11 standard provides.

A NOVEL CALL ADMISSION CONTROL SCHEME IN CELLULAR/WLAN INTEGRATION AND PERFORMANCE ANALYSIS

In order to achieve the Quality of Service(QoS) provisioning and efficient resource utili-zation in cellular network and Wireless Local Area Network(WLAN) integration,an Integrated Ser-vice-Based Call Admission Control(ISB-CAC) scheme is proposed in this paper.The integrated network is modeled by using multi-dimensional Markov chains.The numerical analysis is presented to evaluate the important performance measures such as the blocking probability of originating calls,the dropping probability,and the average transfer time,etc.The steady-state probabilities of the multi-dimensional Markov chains are obtained by using an iterative approach,and the CAC pa-rameters are optimally designed.The analytical model is validated by the computer simulation.It is shown that compared with the conventional WLAN-First Call Admission Control(WF-CAC) scheme,the proposed ISB-CAC scheme not only provides better QoS for mobile users but also utilizes the bandwidth resources more efficiently.

A TRAFFIC OVERSTOCK RESLOVE SCHEME IN WLAN

A new Multiple Access Control (MAC) protocol-User Adaptive Scheduling Multiple Access (UASMA) protocol is proposed in this paper. It can well schedule the packet transmission according to the exact number of active Mobile Terminals (MTs) determined by selforganizing algorithm and adjust the number of packets sent by one node in one frame properly.UASMA protocol employs a special frame structure, which makes it possible to allocate channel resource to uplink and downlink traffic according to their respective service requirements. The proposed concept of referenced-frame-length can ensure the frame length varies in a certain range,and consequently increase the utilization efficiency of the channel greatly. Meanwhile, UASMA protocol uses an efficient collision resolution algorithm to guarantee that active MTs can access the channel rapidly. Finally, the performance of UASMA protocol is evaluated by simulation and it is also compared with carrier sense multiple access, rounding-poll and UPMA protocols. The results show that the UASMA has better performance than others.

Control system design of hybrid fuel cell city bus

This paper introduced the design of the hybrid powertrain of the Fuel Cell City Bus demonstrated in 2008 Beijing Olympic Games. The configuration of the hybrid fuel cell powertrain was introduced. The safety of hydrogen storage and delivery system, the hydrogen leakage alarm system were developed. The real-time distributed control and diagnosis system based on the Time Trigger Controller Area Network （TTCAN） with 10 ms basic control period was developed. The concept and implementation of processor （or controller） monitor and process （or task） monitor technique based on the TYCAN were applied in this paper. The fault tolerant control algorithm of the fuel cell engine and the battery man- agement system were considered. The demonstration experience verified that the fault tolerant control was very important for the fuel cell city bus.

智能QCOS防错控制系统在柔性化生产线中的开发和应用

在汽车柔性生产线中,不同车型在同一工位上可能具有不同数量的QCOS(QualityCon-trolOperationSystem质量控制操作系统)控制点。在这种情况下,现有的QCOS控制盒无法用一种工具完成对不同车型上不同数量的QCOS控制点的控制,因而员工操作容易出错,存在质量风险。针对这一问题,开发出了采用局域控制网总线技术的智能QCOS防错控制系统,仅使用一套拧紧工具扭矩控制系统就能完成对不同车型上不同数量相同扭矩的QCOS控制点的控制,在节省生产资源的情况下提高了质量控制和生产效率。

TPS系统在甲醇项目中的应用

针对大化30万吨甲醇控制系统的组成，主要从硬件构成角度对TPS（Total P1ant Solution）系统的结构组成进行介绍并对系统的可用性和安全性加以介绍。