1000MW火电厂过热汽温控制系统设计及基于多目标优化的控制系统整定

摘 要

过热蒸汽温度控制系统是单元机组不可缺少的重要组成部分，其性能和可靠性已成为保证单元机组安全性和经济性的重要因素。过热蒸汽温度较高时，机组热效率则相对较高，但过高时，汽机的金属材料又无法承受，气温过低则影响机组效率。过热蒸汽温度的稳定对机组的安全经济运行非常重要，所以对其控制有较高的要求。但是由于过热蒸汽温度是一个典型的大迟延、大惯性、非线性和时变性的复杂系统，本次设计采用串级控制以提高系统的控制性能，在系统中采用了主控-串级控制的切换装置，使系统可以适用于不同的工作环境。通过使用该系统，可以使得锅炉过热器出口蒸汽温度在允许的范围内变化，并保护过热器营壁温度不超过允许的工作温度。

首先，我们在控制机制及被控对象的基础上进行探究，根据数学公式和控制策略搭建控制模型，通过MATLAB/SIMULINK仿真，对仿真结果进行分析研究。本次设计主要目的是分析火电厂过热蒸汽温度控制系统的影响外因，建立PID控制的电站锅炉汽温度控制系统方案；根据PID控制系统的要求设计了温度自动控制系统；我们在这个设计方案的基础上，对智能温度控制系统的总体设计方案和总体控制策略进行MATLAB仿真，最终根据仿真结果可以看出，本次设计的控制方法和策略是可行和有效的。

目前我国的电站锅炉都因为具有大惯性、大纯滞后、强干扰性等缺陷，采用最小二乘和相关系数辨识相结合的方法，建立系统数学模型，构造带前馈的串级控制调节器调节主蒸汽温度，控制器外环采用阶梯式广义预测控制，内环为PID控制，设计并使用了智能监督级，保证了先进控制的投用率，实际运行情况表明，该先进控制系统具有良好的控制品质。

随着我国过热蒸汽温度控制技术和智能控制系统的发展，目前行业内相对比较传统的火电厂过热汽温控制无法满足客户的需求。为了传统火电厂在温度波动上得短板问题。在本次毕业设计中，将使用相对先进、快捷、智能的控制机制。该系统的控制大脑为PID控制系统，该火电厂过热蒸汽温度控制系统性价比高、精度准确、能耗较低等特点，给人民生活带来了很大的影响，在市场上很受欢迎。

关键词：过热蒸汽温度；MATLAB；串级控制；波动原因

Abstract

Superheated steam temperature control system is an indispensable part of unit unit, and its performance and reliability have become an important factor to ensure the safety and economy of unit unit. When the temperature of superheated steam is high, the thermal efficiency of the unit is relatively high, but when it is too high, the metal material of the engine can not bear it, and the temperature is too low, the efficiency of the unit is affected. The stability of superheated steam temperature is very important to the safe and economical operation of the unit, so its control has higher requirements. But because the superheated steam temperature is a typical large delay, large inertia, nonlinear and time-varying complex system, this design uses cascade control to improve the control performance of the system, in the system uses the master control - cascade control switch device, so that the system can be applied to different working environment. By using this system, the outlet steam temperature of the superheater can be changed within the allowable range, and the wall temperature of the superheater can be protected from exceeding the allowable operating temperature.

First of all, we explore the control mechanism and the controlled object based on the mathematical formula and control strategy to build a control model, through MATLAB/SIMULINK simulation, simulation results are analyzed. The main purpose of this design is to analyze the influence of thermal power plant superheated steam temperature control system of external factors, the establishment of cascade PID control of power plant boiler steam temperature control system scheme; The automatic temperature control system is designed according to the requirements of PID control system. On the basis of this design scheme, we carry out MATLAB simulation of the overall design scheme and overall control strategy of the intelligent temperature control system. Finally, according to the simulation results, it can be seen that the control method and strategy of this design is feasible and effective.

At present, the power plant boiler is because has the big inertia, pure lag and strong interference, using the least squares method of combining the identification and correlation coefficient, the system mathematical model is set up, structural belt of feedforward cascade control regulator to adjust the main steam temperature, the controller loop adopts cascade generalized predictive control, the inner ring for PID control, the design and use of the intelligent monitoring level, The application rate of the advanced control system is guaranteed. The actual operation shows that the advanced control system has good control quality.

With the development of superheated steam temperature control technology and intelligent control system in China, the traditional superheated steam temperature control of thermal power plants in the industry can not meet the needs of customers. In order to traditional thermal power plants in the temperature fluctuation of the short board problem. In this graduation project, relatively advanced, fast and intelligent control mechanism will be used. The control brain of the system is PID control system. The thermal power plant superheated steam temperature control system has the characteristics of high cost performance, accuracy and low energy consumption, which has brought a great impact on people's lives and is very popular in the market.

Keywords: Superheated steam temperature; MATLAB; Cascade control; Fluctuation reasons

目录

摘       要... 1

第一章 绪论... 5

1.1  研究课题背景... 5

1.2  国内外发展现状... 7

1.3  课题研究的目的及意义... 9

1.4  课题的研究内容及章节安排... 10

第二章 汽温控制系统的组成与对象动态特性... 12

2.1 汽温调节的概念和方法... 12

2.1.1 从蒸汽侧调节汽温... 12

2.1.2 从烟气侧调节汽温... 14

2.2 过热器的分类及其基本结构... 16

2.2.1 过热器的分类... 16

2.2.2 过热器的基本结构... 19

2.3 过热蒸汽温度控制系统的基本结构和工作原理... 20

2.3.1 过热器一级减温控制系统... 20

2.3.2 过热器二级减温控制系统... 21

2.4 过热蒸汽温度控制对象的动静态特性... 23

2.4.1 静态特性... 23

2.4.2 动态特性... 24

第三章 电站锅炉主蒸汽温度控制系统设计... 27

3.1总体设计... 27

3.2  PID控制器设计... 27

3.2.1    PID控制概述... 27

3.2.2    PID控制原理... 28

3.2.3    数字PID控制算法... 30

3.3  主蒸汽温度常规串级控制系统... 32

第四章 主蒸汽温度常规PID控制系统仿真... 34

4.1  基于遗传算法PID参数寻优... 34

4.1.1    遗传算法... 34

4.1.2    基于遗传算法控制器参数寻优方案设计... 36

4.1.3  主蒸汽温度常规PID控制系统仿真... 36

4.2  本章小结... 41

第五章 ....................................................................

完整论文点击如下链接下载:

1000MW火电厂过热汽温控制系统设计及基于多目标优化的控制系统整定资源-CSDN文库

matlab仿真点击如下链接下载：

https://download.csdn.net/download/weixin_45905610/88564773

1000MW火电厂过热汽温控制系统设计及基于多目标优化的控制系统整定-matlab资源-CSDN文库