摘  要

大遲延對(duì)象的控制一直是控制領(lǐng)域研究的焦點(diǎn)問(wèn)題。加熱爐溫度控制便屬于這類復(fù)雜的控制對(duì)象。對(duì)于無(wú)滯后或滯后比較小的系統(tǒng),通常采用PID控制。對(duì)于大滯后系統(tǒng)，PID控制效果并不好，需要另加補(bǔ)償，因此提出了Smith預(yù)估補(bǔ)償控制。而 Smith 預(yù)估算法則在模型匹配時(shí)具有好的性能指標(biāo)，但是由于這種算法嚴(yán)重依賴模型的精確匹配 ,而在實(shí)際中這是很難做到的,當(dāng)模型失配時(shí)，Smith 預(yù)估算法就難以取得良好的控制效果,因此提出了改進(jìn)型Smith控制系統(tǒng)。

本文具體討論了純滯后系統(tǒng)的Smith預(yù)估器，著重對(duì)這種控制算法進(jìn)行了較深入的討論，并提出了一種改進(jìn)型Smith預(yù)估控制器，該控制器把自適應(yīng)控制與Smith預(yù)估器有機(jī)地結(jié)合起來(lái)，實(shí)現(xiàn)對(duì)控制系統(tǒng)的參數(shù)自整定。仿真實(shí)驗(yàn)中，采用Smith預(yù)估補(bǔ)償控制，系統(tǒng)響應(yīng)迅速。若保持控制器和模型的參數(shù)不變，改變對(duì)象參數(shù)，使估計(jì)模型與之失配，此時(shí)Smith預(yù)估算法出現(xiàn)振蕩，系統(tǒng)穩(wěn)定性被破壞。改進(jìn)型Smith算法不僅能夠保持系統(tǒng)的穩(wěn)定，而且振蕩次數(shù)少，收斂速度快。

關(guān)鍵詞:加熱爐；增益自適應(yīng)；Smith預(yù)估器


 

Abstract

Large delay time has been the focus of research in the control field. Furnace temperature control belongs to this complex control object. For no or less delay, the system usually adopts PID control. For large delay system, PID control effect is not good, need additional compensation. Thus puts forward Smith-predictor compensator control . The Smith-predictor in the matching model has good performance when, but this algorithm heavily depends on the exact match model, but it is difficult to do in practice. Smith-predictor algorithm is difficult to obtain good control effect when the model mismatch. Thus put forward an improved Smith-predictor control system.

    This paper discuss the Smith- predictor for pure time-delay system, focusing on such a control algorithm for a more in-depth discussion, and puts forward an improved Smith – predictor, which puts adaptive control and Smith – predictor implement organically, realize to the parameters of the control system to achieve self-tuning. In simulation experiment, use Smith-predictor compensator control, the system responses rapidly. If keep the controller and the model parameters constant, change the object parameters that mismatch model to Smith-predictor, Smith-predictor algorithm oscillation occurs and, the system stability were destroyed at this time. The improved Smith – predictor algorithm not only can keep the system stability but also decreases oscillation frequency, increases convergence speed.

Keywords: furnace; gain adaptive control; Smith-predictor


 


 


 


 


 




目 錄

第一章 緒論 1

1.1  研究的背景及意義 1

1.2  國(guó)內(nèi)外基于加熱爐溫度控制的研究現(xiàn)狀 1

1.3  課題研究的內(nèi)容 3

第二章 傳統(tǒng)的加熱爐概述 4

2.1  加熱爐及其模型的建立 4

2.1.1  加熱溫度控制系統(tǒng)總體結(jié)構(gòu)圖 4

2.1.2  加熱溫度控制系統(tǒng)模型的建立 4

2.2  加熱爐結(jié)構(gòu)及工作方式 5

2.2.1  加熱爐結(jié)構(gòu) 5

2.2.2  加熱爐工作方式 6

第三章 PID控制理論 8

3.1  PID控制算法 8

3.1.1  模擬PID調(diào)節(jié)器 8

3.1.2  數(shù)字PID控制算法 8

3.2  PID的參數(shù)整定 9

第四章 改進(jìn)型Smith預(yù)估器控制理論 12

4.1 Smith預(yù)估器控制理論 12

4.2 改進(jìn)型Smith控制理論 14

4.2.1 增益自適應(yīng)Smith預(yù)估補(bǔ)償控制 14

4.2.2 完全抗干擾的Smith預(yù)估補(bǔ)償控制 15

第五章 加熱爐溫度控制系統(tǒng)仿真研究 17

5.1 PID控制系統(tǒng)仿真研究 17

5.2 Smith控制系統(tǒng)仿真研究 18

5.3  Smith控制系統(tǒng)加擾動(dòng)仿真研究 19

5.4  增益自適應(yīng)Smith控制系統(tǒng)仿真研究 20

總 結(jié) 22

參考文獻(xiàn) 23

謝 辭 24