【作者】 陶涛；

【导师】 孟祥印；

【作者基本信息】 西南交通大学 ， 机械工程（专业学位）， 2018， 硕士

【摘要】 随着国民经济的迅速发展,智能化仪表已逐步取代传统机械式指针计量表,推动着天然气测控领域自动化的飞速发展。在天然气场站、调压站等场站测控系统(Station Control System,SCS)中,信号量多以4-20mA模拟信号和非总线式数字量为主,每一个模拟量设备至少需要2根信号传输线,每一个非总线式数字量需要3根信号传输线,故随着测控点的增加,从现场到控制室的信号传输线将成倍的增加,由于其距离从几十米到几百米不等,则电缆的铺设周期较长和成本较高,系统的安装以及后期维护将会变得较为复杂,同时系统的稳定性也会下降。鉴于此,本文提出了利用现场总线来代替原有数据采集和传输方式从而减少电缆走线数量。在天然气场站测控系统中,以太网常作为上位机与现场测控系统的唯一数据传输通道。而当单一的数据传输通道(以太网或现场总线)发生故障时,数据传输将会直接中断,现场状态得不到实时监控,可能会造成不可估量的危害。考虑于此,本文提出了给以太网和现场总线原有传输方式均提供一组无线冗余通讯方式,使得在有线通信通道异常时,系统通过相应的冗余无线通信方式保证数据稳定传输。整个设计开发过程中,首先对国内外现状进行研究分析,然后根据功能需要,选择STM32为MCU,以及合适的通信芯片及其相应的外围芯片。利用Altium Designer进行电路原理图绘制和PCB设计与制作。结合Keil-MDK进行MCU软件设计与撰写。以QT5.8为平台设计并开发了上位机通信参数配置软件,为使用者提供无代码更新与下载的参数修改方式。结合以上方法与步骤,最终实现了一整套双冗余通信设备设计开发。本文采用的现场总线通信为CAN总线,两类无线通信分别是GPRS通信和ZigBee通信。其中以太网和GPRS通信形成冗余通信,CAN总线和ZigBee形成冗余通信。设计的冗余设备包含网关端模块和终端模块两类模块。经试验表明,该双冗余通信测控设备实现了自主通信方式切换,保证了上位机与现场的数据不中断传输。更多还原

【Abstract】 With the rapid development of the national economy,intelligent instrumentation has gradually replaced traditional mechanical pointer meters,which has promoted the rapid development of automation in the field of natural gas measurement and control.In the Station Control System,such as the natural gas gate station and the regulator station,the signal quantity is mostly based on 4-20 mA analog signal and non-bus digital quantity.At least 2 signal transmission lines are required for each analog device,and 3 signal transmission lines are required for each non-bus-type digital quantity.Therefore,with the increase of measurement and control points,the signal transmission lines which are from the site to the control room will increase exponentially.Because of its distance ranging from tens of meters to hundreds of meters,the building period of the cable will be longer and the cost will be higher.The system’s installation and post-maintenance will be more difficult,and at the same time,the stability of the system also will decline.In view of this,this article has proposed using the field bus to replace the original method of data collection and transmission,so as to reduce the number of cables.In the Station Control System of natural gas,Ethernet is commonly used as the only way of transmission between the host computer and the field control system.If the only way of transmission(Ethernet or the field bus)fails,the data transmission will be interrupted directly,and the field control system will not be monitored in real time,it may cause inestimable damage to the local area.In this regard,a set of wireless redundant communication methods are provided to Ethernet and field bus respectively in the paper,to ensure that the system will use corresponding redundant wireless communication when the wired communication is abnormal.In the whole design and development process,first we studied and analyzed the current situation at home and abroad,and then chose STM32 as MCU,and appropriate communication chip and its corresponding peripheral chips according to the function needs.The circuit schematic and the design and production of PCB were made by using Altium Designer.Then we designed and wrote MCU software with Keil-MDK.With QT5.8 as the platform,the host computer communication parameter configuration software was designed and developed to provide the parameter modification method without code update and download.Combined with the above methods and steps,a complete set of double redundant communication devices was designed and developed.The field bus used in this article is a CAN bus,and the two types of wireless communication is GPRS communication and ZigBee communication respectively.Ethernet and GPRS communication form redundant communication,and CAN bus and ZigBee form redundant communication.The designed redundant equipment includes two types of modules: a gateway module and a terminal module.The tests showed that the double redundant communication measurement and control equipment realized that the switching of the autonomous communication mode,which ensured that the uninterrupted transmission of data between the host computer and the filed.更多还原