D201776 METSO 分散控制系统

分散控制系统（DCS）介绍

1、基本概念

分散控制系统英文简称为DCS（Distributed Control System），具备分散布置、集中控制的特点，应用于各种过程自动控制系统。

2、DCS系统的组成

DCS系统由硬件和软件两大部分组成。

（1）硬件包括：工程师站、操作员站、历史站、I/O卡件、通讯卡件、现场控制站等。

工程师站和操作员站本身就是电脑，之所以叫不同的名称，是因为每一台电脑安装的软件和具备的功能不同，在实际应用中充当的角色也不同，同时代表着权限的不同。

① 工程师站：简称ENG,是电脑安装了组态软件，是现场专业工程师用于编写、修改控制逻辑程序，包括修改图形、参数设置、数据库组态、离线查询等等，它的权限高于操作员站，可把它比作“后台”理解。

② 操作员站：简称OPS或OPU，是电脑安装了操作员软件，它是生产工艺系统的操作员用于监视、操作调整、在线查询、报警等等，它的权限要低于工程师站，可把它比作“客户端”理解。

③ 历史站：是用来存储历史数据的，包括历史曲线、历史报警、历史操作记录等，历史站可以是单独也可跟工程师站、操作员站合并在一起，就是一台电脑既是历史站，也是工程师站或操作员站。

④ I/O卡件：是按照一定的需求和比例布置在各个控制柜内，“I”意为输入，是现场的信号进入DCS系统的；“O”意为输出，是由DCS系统发出的信号，所以有些卡件被称为输入输出模块，由于输入输出的信号分为不同的类型，所以I/O卡件按照作用也分为不同类型的卡件，主要的还是模拟量输入（AI）卡件、模拟量输出（AO）卡件、开关量输入（DI）卡件、开关量输出（DO）卡件。

⑤ 通讯卡件：是用于接收和发送数据信号用的，可以是DCS系统与系统之间，也可是DCS系统与不同的系统、不同设备之间进行通讯，是基于某种类型的协议，通过发送、传输、接收、解析来实现数据的获取和显示。通讯是基于某种协议的，常见协议或通讯有TCP/IP、Modbus、OPC等。

⑥ 现场控制站：是布置I/O卡件的控制柜，一般控制柜内布置由CPU控制器、各类I/O卡件、供电电源、网络交换设备以及各种连接线。若单台控制柜的空间不能布置一个系统信号点数的卡件，可以再加一面柜子，所以就有了主柜（带CPU控制器）和扩展柜。

D200137

Distributed control System (DCS) introduction

1. Basic concepts

Distributed Control System (DCS) has the characteristics of distributed layout and centralized control, and is used in various process automatic control systems.

2, the composition of DCS system

DCS system consists of two parts: hardware and software.

(1) Hardware includes: engineer station, operator station, history station, I/O card, communication card, field control station, etc.

The engineer station and the operator station are computers themselves, the reason why they are called different names is that each computer installs different software and has different functions, plays different roles in practical applications, and represents different permissions.

① Engineer station: ENG, is the computer installed configuration software, is the field professional engineers used to write, modify the control logic program, including modifying graphics, parameter Settings, database configuration, offline query, etc., its authority is higher than the operator station, it can be likened to “background” understanding.

② Operator station: referred to as OPS or OPU, is the computer installed operator software, it is the production process system operator for monitoring, operation adjustment, online query, alarm, etc., its authority is lower than the engineer station, it can be likened to “client” understanding.

③ Historical station: is used to store historical data, including historical curves, historical alarms, historical operation records, etc., the historical station can be alone or combined with the engineer station and operator station, that is, a computer is both a historical station, but also an engineer station or operator station.

④ I/O card: is arranged in each control cabinet according to certain needs and proportions, “I” means input, is the field signal into the DCS system; “O” means output, is the signal sent by the DCS system, so some cards are called input and output modules, because the input and output signals are divided into different types, so I/O cards are also divided into different types of cards according to the role, The main ones are analog input (AI) cards, analog output (AO) cards, switching input (DI) cards, and switching output (DO) cards.

⑤ Communication card: is used to receive and send data signals, can be between DCS system and system, but also DCS system and different systems, different equipment communication, is based on a certain type of protocol, by sending, transmission, receiving, parsing to achieve data acquisition and display. Communication is based on a certain protocol, common protocols or communication are TCP/IP, Modbus, OPC and so on.

⑥ Field control station: It is a control cabinet for arranging I/O cards. Generally, the control cabinet is arranged by CPU controllers, various types of I/O cards, power supply, network switching equipment and various connection lines. If the space of a single control cabinet cannot be arranged with a system signal point card, a cabinet can be added, so there is a main cabinet (with a CPU controller) and an expansion cabinet.