【作者】 曾辉；

【导师】 周伟；

【作者基本信息】 武汉理工大学 ， 计算机应用， 2002， 硕士

【摘要】 基于现场总线技术的集散控制系统是一种新型的控制系统，它是采用总线方式将现场控制单元、现场监视单元、操作站、通信接口单元连接起来，综合了计算机技术、通信技术和过程控制技术，采用了多层次分级的结构形式，以适应现代高水平生产控制与管理的需要。它继承和发展了常规仪表控制系统和计算机集中控制系统的优点，又弥补了它们各自的不足，以崭新的结构体系、先进的技术面貌、复杂的信息处理功能和独具风格的控制方式应用于石油、化工、治金、电力、纺织、造纸、食品和水处理等各个工业生产领域，已经逐步成为过程控制系统发展的主流，它的优点在于网络结构简单，且通信电缆少，布线容易，节省材料和费用，减少了维护工作量。本论文通过对集散控制系统(DCS)与现场总线控制系统(FCS)的研究，阐述了集散控制系统发展到现场总线控制系统的进步性。同时，论文分析现场总线的体系结构、功能、类型，比较集散控制系统与现场总线控制系统的区别，并对比RS-485技术与CAN技术在实际应用中的差异。 在此理论基础上，论文提出了一种应用于印刷业张力联动控制的基于现场总线技术的集散控制系统DCS2000-MRT，介绍了该系统的主要功能、硬件组成、工作原理、软件设计及其实现方法。该系统实现了功能分散控制，对过程参数检测及运算处理、控制策略的实现、控制信息的输出以及过程参数的实时控制等都在现场的过程控制单元中有效地、长期可靠地、无人干预地自动进行，从而实现控制功能的高度分散。该系统的现场总线智能化模块层由分散在控制现场的若干个智能化单元组成。智能仪表采用功能模块结构，通过设计可以完成类似于检测、张力控制、速度控制等功能。整个系统设计时既可以采用RS-485技术，又可以采用CAN技术，它具有全数字化信息双向通信、多变量处理能力、自诊断等功能，系统中的各智能化单元工作独立，又可相互通信，在系统总线上，用户可以根据需要自由组态，灵活实现各种现场功能。系统同时集中了DCS系统和现场总线系统的优点。在本论文中，以该应用系统的一个智能化单元——浮辊张力控制单元为具体分析对象，详细描绘其组 武汉理工大学硕士学位论文 成方式、工作原理、程序设计方法以及工作特点，对比了使用RS－485 总线技术进行通信与使用CAN总线技术进行通信的不同，较好地体现了 丛于观场总线技术的染敝控制系统介实际工业应用中的优拎和特点。更多还原

【Abstract】 Distributed control system based fieldbus is a new kind of control system, it connects UFCH, UFMH, UOPS, ULFS by databus mode. It integrates computer technology, communication technology and process control technology, adopts multi-layers frame to adjust to demand of high standard productive control and management. It developments and follows the advantages of traditional instrument control system and computer central control system and make up for their disadvantages so that it is applied in oil, chemistry, mineral, electricity, silk, food and water est. with its new frame, modern technology, complex information and unique control mode. It has become mainstream in process control system. Its advantage is simple frame, few cable, saving materials and fees, decrease of maintenance. This paper proposals the research in distributed control system (DCS) and fieldbus control system(FCS) and describes the progresses from DCS to PCS. Then this paper analyzes fieldbus’s frame, function, category, compares distributed control system and fieldbus control system, distinguish between RS-485 and CAN in practice application.Under the theory, this paper comes up a DCS based fieldbus and named DCS2000TMRT that is applied in tension control in package factory, this paper recommended its main function, hardware frame, work principles and software design. This system has function dispersion and can deal with parameter checking, calculation, control strategy, information output and process parameters time-control. These functions will auto-run effectually and reliably that make control dispersion. Fieldbus intelligential model layer in this system is made of a few intelligential models in the fields. Intelligential instruments adopt functional model frame and has detection, tension control and speed control etc. The design of the whole system adopt not only RS-485 but also CAN. It has whole digital bilateral communication, multi-parameters deal, self-check etc. In the whole system, each intelligential unit work independently and intercommunicate. The users can freely configure to realize kinds of functions according to their demands. So this system integrates advantages of DCS and fieldbus. This paper takes oneintelligential unit-mobile roll tension control unit as concrete object toanalyze. Its frame, principle, program and character are purposed. During this purpose, difference between RS-485 and CAN in communication are discussed. Then this system’s advantages and characters are recommended in practice industrial application.This paper discusses the process of industrial control system thatdeveloped from distributed control system to fieldbus control system and its improvement. In the same time, this paper compares RS-485 and CAN. This paper analyzes a concrete example to represent this system’s advantage, such as convenience, common use. Then it interprets distinguish between RS^485 and CAN.更多还原