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为解决扬州某面粉厂年产40万吨小麦面粉储存问题,设计了基于西门子S7 1500 PLC的智能化立体仓库控制系统,该控制系统可以实现小麦面粉全程自动、高效、稳定出入库。面粉存储智能仓库主要分为库东和库西两部分,库西为成品入库和空托盘出库补给面粉码垛区,库东为成品出库、人工拣选和盘点区。仓库控制系统按管理层-控制层-执行层的系统架构设计,分为控制系统硬件设计和控制系统软件设计。系统采用AS-i的现场总线控制方式,通过PLC-网关-AS-i模块实现PLC对设备运行状态和传感器的监控。核心控制器通过TCP/IP通讯协议与仓库控制系统WCS通讯,WCS对PLC下达任务,PLC再控制执行设备动作。通过对控制系统的调试和验证,控制程序运行稳定,WCS与PLC数据通讯稳定。验证表明所设计的控制系统硬件电路功能和控制程序满足设计要求。研究结果可为农产品存储和相关设计研究提供参考。 相似文献
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文章针对自动扶梯空载运行时间长、能耗损失大、寿命低等特点,研究应用PLC与变频器对自动扶梯运行控制,完成控制系统软硬件的设计,通过PLC与变频器对自动扶梯的控制,使得自动扶梯在负载时常速运行,在空载时低速运行,进而降低自动扶梯的能耗、磨损量,增加自动扶梯的使用寿命. 相似文献
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双闭环控制采摘机器人机械手设计——基于PLC和CAN总线 总被引:1,自引:0,他引:1
采用双闭环控制系统,基于PLC运动控制器和CAN总线,提出了一种新的采摘机器人机械手关节分布式控制方案,并采用模块化思想设计了机器人关节电机控制系统、CAN模块及PLC控制器。采摘机器人机械手的关节采用谐波减速器进行调节,利用霍尔传感器和红外线传感器及光电编码器进行图像、转速和障碍物触碰的信号采集,采集信号利用A/D转换器将数据传输给PLC控制器。机械手的执行末端采用CAN总线控制,并利用变频器传递的通信信号,实现了末端执行器的并行控制,使多机械手处于最佳动作状态。最后,在双闭环控制方案的基础上加入了前馈控制环境,利用前馈控制环节可以实现对系统的实时控制,改善了系统的静态性能,实现了机械手对实际采摘位置的有效追踪。实验和仿真模拟表明:位移时间曲线平滑无突变,表明机器人在运行过程中平稳、无振动,机器人工作的可靠性较高,对路径的追踪精度较高。 相似文献
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基于PLC和触摸屏的气流膨化机控制系统 总被引:2,自引:1,他引:1
介绍了应用于气流膨化机上采用PLC、触摸屏、变频器和变送器组成的控制系统,给出了系统的工作流程及其相应的软硬件设计,实现了气流膨化机的全自动控制。 相似文献
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采用西门子S7-1200型PLC作为控制器,Sinamics S120作为加载变频器,构建了基于PROFINET现场总线的两级控制系统,设计并实现了电机综合性能试验台的搭建。测试台能够完成三相异步电机、永磁同步无齿曳引机、永磁同步电机、变频电机等各类电机的精确加载试验。测试装置加载不仅动态控制精度高而且可靠稳定,采用伺服控制方式加载不需要进行转向识别,操作便捷。实际应用表明,该测试台控制精度能够达到预期目标。 相似文献
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本文根据矿用风机控制的实际需求,设计了以PLC为控制核心的风机变频调速控制系统,分析了系统主要的设计流程。该系统将PLC与变频器有机地结合起来,采用以矿井气压压力为主控参数,实现对风机工作过程和运转速度的有效控制,使矿井通风机通风高效、安全,达到了明显的节能效果,为煤矿矿井通风系统的节能技术改造提供一条新途径。 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献