基于dcs的热工协调控制系统毕业设计

毕业设计说明书(论文)

学院：自动化工程学院班级：自动106

专业：☑自动化□测控技术与仪器

所在系：□控制科学与工程□仪器科学与技术

题目：基于DCS的热工系统协调控制设计研究

摘要

摘要

火电厂单元机组协调控制系统是一个多变量被控对象，具有非线性强、参数时变大、迟延等特性，针对这些特性，需要对机组进行解耦控制，然后对控制算法进行改进，使系统更加稳定的运行。常规的自动调节系统是汽轮机和锅炉分别控制。随着单元机组容量的不断增大、电网容量的增加和电网调频、调峰要求的提高以及机组自身稳定（参数）运行要求的提高，常规的自动调节系统已很难满足单元机组既参加电网调频、调峰又稳定机组自身运行参数这两个方面的要求，因此必须将汽轮机和锅炉视为一个统一的控制对象进行协调控制。机炉的控制特性有相当大的差别，锅炉是一个热惯性大、反应很慢的控制对象，而汽轮机相对地是一个惯性小、反应很快的控制对象。

协调控制系统就是充分考虑机炉控制特性的差异以及各自的特点，采取某些措施（如引入某些前馈信号、协调信号），让机炉同时按照电网符合的要求变化，接受外部负荷指令，根据主要运行参数的偏差，协调地进行控制，从而在满足电网负荷要求的同时，保证主要运行参数的稳定。

关键词：DCS系统；协调控制；负荷控制

东北电力大学自动化工程学院学士学位论文

Abstract

Thermal power plant unit coordinated control system is a multi variable object, with strong nonlinearity, time-varying parameters, delay and other characteristics,

according to these characteristics, the need for decoupling control on the unit, then the control algorithm was improved, which made the system more stable operation.

Automatically adjust the conventional system of turbine and boiler control. With the unit capacity increasing, increase the capacity of power grid and power FM, peaking requirements increase and the unit itself (parameters) operation requirements increase, automatic regulating system routine has been difficult to meet the unit in both grid

frequency, peak and stable unit operation parameters of these two requirements, and therefore must be the steam turbine and boiler as a unified control object coordination control. There is a considerable difference control characteristics of turbine and boiler, boiler is a large thermal inertia, the reaction is very slow control object, and the steam turbine is relatively a low inertia, quick response to the control object.

Coordinated control system is considering the different control characteristics of boiler and their respective characteristics, to take certain measures (such as the

introduction of some feedforward signal, signal coordination), let the machine stove at the same time according to the power which meet the requirements of the change,

accept the load instruction outside, according to the deviation of main operational

parameters, control and coordination, so as to satisfy the load requirements of the

power grid, to ensure the stability of main operation parameters.

Key words：DCS system；Coordinated control；Load control

目录

目录

摘要...................................................................................................................................... I Abstract .................................................................................................................................. II 第1章绪论........................................................................................................................ - 1 -

1.1课题意义与背景.................................................................................................. - 1 -

1.2单元机组协调控制系统的设计目的.................................................................. - 1 -

1.3单元机组协调控制系统的研究现状 ............................................................ - 2 - 第2章控制系统概述........................................................................................................ - 3 -

2.1发电厂协调控制系统的基本概念及特点.......................................................... - 3 -

2.2单元机组自动控制的功能及特点...................................................................... - 3 -

2.3协调系统控制方式.............................................................................................. - 4 -

2.3.1机跟炉方式............................................................................................... - 4 -

2.3.2炉跟随方式............................................................................................... - 5 -

2.3.3机炉协调方式........................................................................................... - 5 - 第3章单元机组燃烧与传热过程.................................................................................... - 7 -

3.1炉内燃烧与管道传热.......................................................................................... - 8 -

3.2 汽轮机做功过程................................................................................................. - 9 -

3.3控制系统对模型精度要求................................................................................ - 10 - 第4章年协调控制系统的基本原理及实现.................................................................. - 12 -

4.1协调控制系统的基本原理................................................................................ - 12 -

4.2间接能量平衡协调控制系统介绍.................................................................... - 13 -

4.2.1 补偿锅炉侧扰动的机跟炉协调系统.................................................... - 13 -

4.2.2 补偿汽机侧扰动的机跟炉协调系统.................................................... - 15 -

4.2.3 实现双向补偿的机跟炉协调系统........................................................ - 15 -

4.2.4补偿锅炉侧扰动的炉跟机协调系统..................................................... - 16 -

4.2.5 补偿汽机侧扰动的炉跟机协调系统.................................................... - 17 -

4.2.6 实现双向补偿的炉跟机协调系统........................................................ - 17 -

4.3 单元协调控制系统组成................................................................................... - 18 - 第5章协调系统工程实现.............................................................................................. - 21 -

5.1负荷的形成........................................................................................................ - 21 -