【作者】 王卫华；

【导师】 杨鹏；

【作者基本信息】 河北工业大学 ， 控制科学与工程， 2011， 硕士

【摘要】 在工业自动化当中,可编程控制器、现场总线、智能仪表成为自动控制的核心。它们运用的是否合理,是否有效,直接关系到自控的成本,自控的效果。智能仪表的广泛应用是大势所趋,但目前我国的智能仪表产业化企业不多,价格偏高。这严重制约了现场总线的普及应用。HART智能仪表在国内发展较为迅速,目前HART协议主要用在仪表的调试,校准,日常维护等。把HART仪表组成网络与PLC进行通信,从而直接并入控制系统还不多见。本文针对某个电解液生产自动化系统,将HART总线运用在防爆危险区域,以低成本实现了本质安全的HART仪表组网。在该控制系统中分别用S7-224XP作为控制器,通过自由口协议与HART适配器进行通信,用ADAM-5510M作为控制器,通过串口与HART适配器进行通信,采集模拟量数据,组成生产自控系统。在复剂原料自动进料系统中,将数字式电子秤称重系统与科氏质量流量计计量系统相结合,用S7-224XP作为控制器,并用HART命令读取西门子科氏质量流量计的各主要参数,以及错误报警信号,使系统能够在加料过程中监测到气泡干扰。S7-224XP与4个重量变送器组成网络,用ASCII码协议进行通信,快速读取各重量变送器的当前值,实现计量控制。在上位机中,用组态王6.52作为组态软件,开发组态画面,对生产进行实时监控,记录并存储重要的生产数据。本系统在实施过程中,针对各种物料的性质、具体生产工艺,对各种仪表及阀门进行对比,选择出合适自控操作的仪表及设备。通过实际调试,对HART仪表与安全栅的匹配应用进行优化,以及对ADAM-5510M的两个串口收发HART命令的同步问题做出进一步的改善。系统已经投入生产,运行稳定,相对于PROFIBUS-PA以及FF总线仪表,HART仪表价格价低,国内厂家的生产技术比较成熟。对于中小企业而言,HART总线是一个不错的选择,尤其在防爆危险区域,实现成本底,具有一定的推广价值。更多还原

【Abstract】 PLC, fieldbus and intelligent instruments become the core of industrial automation. Whether the use is reasonable and valid relates directly to the system’s cost and control effect. The wide application of intelligent instruments is inevitable. But the number of enterprise producing intelligent instrument is few, which restricts the popularization and application of the fieldbtiss rapidly that the development of the HART intelligent instruments in china. Now, HART protocol is mainly used in instruments, debugging, calibration and maintenance. It is rare that take the HART fieldbus communicate with PLC directly.In this paper, the control system will be a combination of PLC and HART fieldbus. It is use the free port protocol of S7-224XP to communicate with HART adapter and use the serial communication ports of ADAM-5510M to communicate with HART adapter.In raw material automatic feeding system, combine digital electronic weighing system with Coriolis mass flowmeter metering system. S7-224XP is used as controller, and using HART protocol to communicate with Siemens Coriolis mass flowmeter. The error code is be readed, then the PLC could monitor the bubble disturbance during the process of feeding. S7-224XP composes with four weight transmitters, and read the value of the transmitter through ASCII protomolthpidbper computer, the use of kingview 6.25 as configuration software to build configuration picture, realize real-time monitoring, recording and storage important data.According to the properties of various materials and various production process, choose the proper instruments and valves. Through the practice debugging, the matching between HART instrument and safety barrier was optimized. The tow ADAM-5510M serial ports communication to transfer data synchronously has be further improved.The control system has been put into production, stable operation. Relative to the PROFIBUS instruments and FF instruments, the price of HART instruments is low. Domestic manufacturer production technology is mature. TO small and medium-sized enterprises, HART bus is a right choice, especially in Explosion-proof area. The integration of HART bus and PLC will be worthy of using abroad.更多还原