大滯后對象的預(yù)測控制仿真研究

電氣自動化論文編號:ZD328  論文字數(shù):11599,頁數(shù):29

目　　錄
　　
 一引言 1
 1.1大滯后對象的控制難點 1
 1.2大滯后對象的控制方法 1
 1.2.1PID控制 1
 1.2.2Smith預(yù)估控制 1
 1.2.3Dahlin算法 2
 1.3課題的提出 2
 二預(yù)測控制 3
 2.1預(yù)測控制提出的背景 3
 2.2預(yù)測控制的特點及基本思想 3
 2.3預(yù)測控制的基本原理 3
 2.3.1預(yù)測模型 4
 2.3.2滾動優(yōu)化 4
 2.3.3反饋校正 4
 2.4預(yù)測控制算法 4
 2.4.1模型算法控制 4
 2.4.2動態(tài)矩陣控制 5
 2.4.3廣義預(yù)測控制 5
 2.5預(yù)測控制的發(fā)展前景 5
 三模型算法控制 7
 3.1內(nèi)部模型 7
 3.2反饋校正 8
 3.3參考軌跡 9
 3.4滾動優(yōu)化 9
 四大滯后對象的模型算法控制 11
 4.1不含滯后對象的模型算法控制 11
 4.2大滯后對象的模型控制算法 12
 4.3算法實現(xiàn)與仿真分析 13
 4.3.1求內(nèi)部模型 13
 4.3.2算法實現(xiàn)與仿真分析 13
 五基于預(yù)測偏差的模型算法控制 17
 5.1預(yù)測穩(wěn)態(tài)差 17
 5.2基本原理 17
 5.3算法實現(xiàn)與仿真分析 18
 5.3.1求內(nèi)部模型 18
 5.3.2算法實現(xiàn)與仿真分析 18
 六總結(jié) 21
 謝辭 22
 參考文獻 23
 附錄 24

摘　　要
 
 大滯后對象在工業(yè)過程中是非常普遍的，而在過程控制領(lǐng)域中這是一個難點。大滯后的存在嚴重地影響了系統(tǒng)的穩(wěn)定性,導(dǎo)致系統(tǒng)的超調(diào)量變大,調(diào)節(jié)時間大大加長,甚至出現(xiàn)振蕩、發(fā)散,系統(tǒng)的動態(tài)品質(zhì)明顯變差。常規(guī)的控制算法,例如：PID控制、Smith預(yù)估控制、Dahlin算法控制,已經(jīng)很難滿足工業(yè)過程的要求。針對大滯后對象難控的特點，本文引入了預(yù)測控制，它具有適應(yīng)性強、響應(yīng)速度快、超調(diào)量小、調(diào)節(jié)時間短、魯棒性強等特征,而且對模型的精確度要求也不高,可以很好地控制大滯后系統(tǒng)。本文在深入研究預(yù)測控制的發(fā)展、基本思路、控制算法的基礎(chǔ)上，著重研究模型算法控制(MAC),并將其應(yīng)用于控制大滯后對象,通過算法實現(xiàn)與MATLAB仿真，并與PID控制比較，驗證了此種方法的有效性。由于模型算法控制大滯后對象的輸出呈階梯型，而且遲延時間越大，階梯越寬。因此，本文又提出了一種基于預(yù)測偏差的模型算法控制（PEBMAC）,并通過算法實現(xiàn)與仿真，驗證了它的有效性。

關(guān)鍵詞:大滯后　　預(yù)測控制　　模型算法控制
Simulating Research on Predictive Control of a Long time-delay Target
ABSTRACT
 
 The long time-delay targets are very widespread in the industrial processes, and it is difficulty in the control domain. Its existence affects the stability of the system seriously, causes system overshoot becoming big, makes settling time become long consumedly, or even appear to oscillation and divergence. The dynamic quality of system also becomes obviously bad. The conventional control algorithms are difficult to satisfy the requests of the industrial process, such as, PID control, Smith predictor control, Dahlin algorithm control. For the characteristics of the long time-delay target being difficult to control, the predictive control is proposed in this paper, and its characters are good self-tuning ability, fast response, little overshoot, short settling time and strong robustness, etc. It has higher control precision without the necessary of precise model, so it can control the long time-delay target. On the base of the deeply study the development, basic ideas and control algorithms of the predictive control, this paper emphasizes on researching the model algorithm control (MAC), and uses it to control the long time-delay target. The simulation results show that this approach is effective by the algorithm, MATLAB simulation, and the comparison with PID control. The output of the long time-delay target which is controlled by the model algorithm control is stepped. Moreover, the longer the time-delay is, the wider the step is. Therefore, the paper proposes a model algorithm control that based on the predictive error (PEBMAC), and the results show this approach is very effective by the algorithm and simulation.

Key words : Long time-delay　　Predictive control　　Model algorithmic control