UPS电源的电池老化造成DCS系统规律性跳停故障

##正##我公司回转窑系统的控制采用杭州和利时公司的SMARTPRO系统,并分为2个控制站,10号站主要负责立磨部分,因为距离较远,所以通过光纤与上位机联系;11号站主要负责窑系统,通过网线与上位机联系,此系统运行将近三年,一直都很稳定。     

滚镀过程中电流密度在线监控系统的设计

针对滚镀过程中电流密度随机多变的特点,设计出一套能够在线监控滚镀过程中电流密度的闭环系统。介绍了该系统的架构,并详细阐述了上位机、高频电源模块和电流密度采集设备的设计思路。设计的闭环系统借助磁敏感传感器采集并经换算获取滚镀过程中的实时电流密度,并将其反馈至控制芯片,通过控制高频电源模块的输出,实现对滚镀过程中电流密度的在线监控。     

基于S7-300 PLC与WINCC的锅炉液位控制系统

系统设计以西门子公司的S7-300PLC作为数据采集及控制单元,配合各种检测和控制设备对锅炉液位进行控制。上位机通过西门子的上位机监控软件WinCC和各站进行数据交换,从而实现集中控制。     

基于PC机和单片机的主从式测控系统

采用MAX232芯片作为主从式测控系统上位机(PC机)与下位机(单片机)之间的电平转换单元,实现上、下位机正常对接的目的,并通过串口实现上位机与下位机之间的通信。Proteus软件的仿真测试结果表明:该系统能够实现对单片机的电机控制模块和交通灯控制模块的控制。     

Design of Master-Slave Control System Based on PC and MCU

采用MAX232芯片作为主从式测控系统上位机(PC机)与下位机(单片机)之间的电平转换单元,实现上、下位机正常对接的目的,并通过串口实现上位机与下位机之间的通信.Proteus软件的仿真测试结果表明:该系统能够实现对单片机的电机控制模块和交通灯控制模块的控制.     

基于QNX和力控6.0的高压脉冲电源监控系统设计

高压脉冲电源是中性束注入加热装置中的主要系统之一。通过实时操作系统QNX与光信号相结合,来实现电源模块的投切,进而得到设定的电压值。考虑到模块的安全运行,采用光纤TCP/IP网络采集各电源模块的状态,实现了电源模块的实时监控。考虑到模块输出的最高电压达100 kV,因此,包括主控计算机和监控计算机在内的所有与模块的通讯,都采用光纤实现,提高了整个系统的可靠性和安全性。通过对十五个电源模块的模拟调试,可以看出,基于QNX和力控6.0的100 kV/100 A高压脉冲电源监控系统是切实可行的。     

候车室环境检测控制系统设计

候车室环境检测控制系统包含上位机和下位机两部分。其中下位机以STC89C52RC单片机为核心,辅以红外传感器、温度传感器、烟雾传感器和光敏电阻等实现对候车室环境参数进行监控,达到信息显示、温度检测控制、人流量控制、有害气体检测控制、照明强度控制等功能。上位机界面包括基本环境参数设置、手动控制和自动控制切换、参数显示功能、风扇控制、喷淋控制和照明控制等功能。通过联机调试表明,本系统上下位机通信情况良好,可以实现上位机对下位机的控制,同时也可以实现上位机实时显示下位机所检测的参数信息。该系统具有操作简单、显示界面简洁易懂、系统设备可靠性高、可以动态显示所有数据参数等优势,适用于中小型铁路客运站候车室。     

基于VB的多路温度检测系统设计

为了实现温度的多点检测,采用传感器将温度数据转换为数字信号,以单片机为核心,读取并显示温度数据,同时采用RS485串行通信,使下位机测温模块与上位机实现双向通信,继而完成上/下位机的温度显示、报警及上位机报警控制等。上位机界面采用VB编写而成,作为系统中心,联络各下位机模块。由于RS458可以一对多双向远距离通信,多个下位机模块与上位机相连,实现常规温度（0～120℃）下的温度值多点远程监测。     

基于RFID智能停车场收费管理系统设计与实现

为提高停车场的经济效益和运行效率,实现自动化、智能化的管理,结合“防疫无接触管理”的趋势要求设计了一种基于RFID智能停车场收费管理系统。本系统设计主要以STC89C52单片机为控制核心,RC522无线射频模块、红外避障传感器模块、电源模块、蜂鸣器模块等硬件设计完成车辆的自动进出及交互功能,结合上位机,12864液晶模块及按键模块实现车辆信息查询及收费功能。结果表明,系统实际运行可满足无接触管理要求,实现了停车场的自动化管理。     

用上位机控制变频器的实现方案

针对变频器和上位机的控制问题,在上位机和PLC联网现有模式的基础上,提出一种新的控制方式,实现了用上位机控制变频器的各项操作,达到工艺控制的要求,并在冷却窑的排汽风机上成功实现。     

中空纤维PVA/PAN复合膜填料的乙醇水溶液精馏性能

以乙醇/水溶液为分离对象,中空纤维PVA/PAN复合膜作为精馏填料,考察了不同膜组件的传质分离效率。实验结果表明:各种组件的分离效率均随塔釜加热功率的增加而减小;和大多数中空纤维膜接触器一样,其总传质系数Ky随中空纤维膜组件填充密度φ的增加而减少;相比于传统精馏填料而言,用中空纤维膜做精馏填料分离乙醇水溶液的分离效果更好,可以在常规填料不能操作的液泛线以上进行操作。当塔釜加热功率为120 W,45根中空纤维膜封装在内径为1.6 cm玻璃管中的传质单元高度(HTU)为5.64 cm。     

Experimental analysis and theoretical modeling of the mechanical behavior of short glass fiber and short carbon fiber reinforced polycarbonate hybrid composites

In this research, polycarbonate (PC) composites with short glass fiber (SGF) and short carbon fiber (SCF) hybrid fiber reinforcements were compounded by single screw extruder and specimens were prepared by injection molding machine. This article aims to investigate the mechanical properties of PC hybrid composites, by means of the experimental and the theoretical methods. The composites were subjected to tensile test. Experimental results showed the improvements in tensile strength and modulus by increasing the SCF content of the hybrid composite. The theoretical tensile strength was predicted based on Kelly–Tyson model and rule of hybrid mixture. Kelly–Tyson model showed to be a good approximation to predict the tensile strength of composite. When the SCF was replaced by milled carbon fiber (MCF) to form a PC/SGF/MCF hybrid system, poorer mechanical properties are reported due to the weaker interfacial adhesion between MCF and PC, as proven by the scanning electron microscopy. POLYM. COMPOS., 37:1238–1248, 2016. © 2014 Society of Plastics Engineers     

PC/PET共混物流变性及可纺性

用熔融共混法制得一系列PC/PET共混物,通过Instron流变仪,小型纺丝机,差示扫描量热,广角X光衍射和热收缩等实验对PC/PET共混体系的流变性及可纺性进行研究。讨论了PC含量对流变参数及可纺性的影响。结果表明,PC/PET共混熔体属切力变稀流体,在PC含量小于15%(mol比)时有较好的可纺性及纤维力学性能,PC/PET共混拉伸丝是一种高收缩纤维。     

Experimental investigation on solid dispersion,power consumption and scale-up in moderate to dense solid–liquid suspensions

Detailed particle concentration distribution in dense solid–liquid suspension was measured by means of fiber optic probes. The effect of solid loading, impeller speed, and impeller type and clearance was investigated. Results were compared with modeling approaches to show the accuracy of sedimentation–dispersion model and its capability to describe complex phenomena taking place in dense liquid–solid mixing systems. Variation of power numbers by changing impeller clearance and solid loading were also investigated. It was shown that the impeller power number for a slurry system exhibited different trends in a moderate or dense liquid–solid system. In addition, scale-up rules to achieve the same level of homogeneity on a large scale as the laboratory scale were evaluated.     

The morphology,mechanical properties,and flammability of aligned electrospun polycarbonate (PC) nanofibers

The electrospinning of the polycarbonate (PC) solutions was performed for the variable electrospinning parameters such as polymer concentration, solvent composition, applied voltage, flow rate, and take‐up velocity in order to evaluate changes of morphology, mechanical properties, and flammability of the aligned PC nanofibers as a function of the electrospinning parameters. It was found that the ratio of THF/DMF solvent in the electrospinning parameters had a major effect on the spinnability and fiber morphology. Furthermore, it was confirmed that the mechanical properties were dependent upon the fiber morphology. The spinnability of the PC solutions with a lower THF ratio in THF/DMF solvent was poor. The aligned electrospun PC fiber with the best morphology was made in the range of polymer concentration of 22%, solvent ratio of 50:50 THF : DMF, applied voltage of 14 kV, flow rate of 0.050 ml/m, and a take‐up velocity of 7.3 m/s. The ultimate strength and initial modulus of the 80% drawn 22% PC fiber were 64 ± 2 MPa (commercial 55–75 MPa) and 1.9 ± 0.1 GPa. The heat release capacity (HRC) of the 22 and 25% PC fiber were 275 ± 27 J/g K and 198 ± 1 J/g K. It was found that the flame resistance of the electrospun PC nanofiber was superior to that of the PC raw material (HRC ～360 J/g K). POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

AS-g-MAH增容PC/ABS合金的研究及应用

研究了增容剂马来酸酐接枝(丙烯腈/苯乙烯)共聚物(AS-g-MAH)对PC/ABS合金加入玻璃纤维(GF)前后力学性能的影响,并采用扫描电子显微镜观察了PC/ABS合金加入增容剂及GF前后的微观结构。结果表明,AS-g-MAH的加入使PC/ABS合金的力学性能得到提高;微观形貌特征和力学性能试验结果完全相符。制得的增容改性PC/ABS合金可满足安全边界条和导向轮材料的要求。     

Rheological hybrid effect in dually filled polycarbonate melt containing liquid crystalline polymer

Polycarbonate (PC)/liquid crystalline polymer (LCP) blends dually filled with glass fiber and nano‐SiO₂ were prepared by melt blending, with the use of a commercial Vectra A130 as the source of LCP and glass fiber. In these dually filled PC/LCP melts, rheological hybrid effect occurred, confirmed by the melt viscosity of the quadruple polymer blends decreased with increasing nano‐silica loading, influenced by the minor LCP phase in the blend. The drastic viscosity reduction closely correlates with the deformation and fibrillation of LCP droplets in the system. The LCP fibrillation was controlled jointly by the thermodynamic and hydrodynamic driving forces. Finally, the dually filled PC/LCP melt had decreased viscosity lower than those of pure PC, silica‐filled PC, and PC/Vectra A130 blends, and furthermore had decreased glass fiber breakage, shown by larger average aspect ratio than that in PC/Vectra A130 blends. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers     

Mechanical and morphological properties of carbon fiber reinforced–modified epoxy composites

Epoxy, prepared through aminomethyl 3,5,5‐trimethylcyclohexylamine hardening of diglycidylether of bisphenol‐A (DGEBA) prepolymer, toughened with polycarbonate (PC) in different proportions, and reinforced with carbon fiber, was investigated by differential scanning calorimetry, tensile and interlaminar shear strength testing, and scanning electron microscopy (SEM). A single glass transition temperature was found in all compositions of the epoxy/PC blend system. The tensile properties of the blend were found to be better than that of the pure epoxy matrix. They increased with PC content up to 10%, beyond which they decreased. The influence of carbon fiber orientation on the mechanical properties of the composites was studied, where the fiber content was kept constant at 68 wt %. Composites with 45° fiber orientation were found to have very weak mechanical properties, and the mechanical properties of the blend matrix composites were found to be better than those of the pure epoxy matrix composites. The fracture and surface morphologies of the composite samples were characterized by SEM. Good bonding was observed between the fiber and matrix for the blend matrix composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3529–3536, 2006     

PBO用于绝缘微型光缆增强材料的研究

特殊环境对微型光缆加强材料的要求越来越高。通过对高强微型光缆的结构及非金属加强材料的使用强度要求的研究,采用立式圆形编织机,按照一定的工艺进行编织来研制PBO高强度微型套管。测试结果表明:PBO纤维的拉伸强度、安全使用温度高于目前普遍使用的Kevlar-49纤维和S玻纤等非金属加强材料,3种纤维的理论最大抗拉力分别为1 989 N、960 N、892 N。为此,在抗拉强度要求极高的特殊环境里,PBO纤维是目前微型光缆最佳的非金属绝缘加强材料。