【摘要】：火電機組SCR脫硝系統(tǒng)的非線性、時滯和時變特性,給實際控制增加了難度。近來隨著大氣環(huán)境的惡化,對火電機組氮氧化物的排放標(biāo)準愈加嚴格,對SCR脫硝系統(tǒng)控制性能的要求也更高,因此有必要尋求性能良好的控制算法。滑�？刂谱蕴岢鲆詠�,由于極強的魯棒性,在非線性、時變系統(tǒng)控制中效果良好,因而受到廣泛關(guān)注,已成功應(yīng)用于機器人、航空航天等領(lǐng)域。本文在完成大唐洛陽雙源熱電廠改造項目中脫硝系統(tǒng)改造的基礎(chǔ)上,對脫硝系統(tǒng)的特性和現(xiàn)階段脫硝系統(tǒng)控制中存在的問題進行了分析。隨后,從理論與應(yīng)用相結(jié)合的角度出發(fā),針對滑�？刂频男阅芎投墩竦确矫孢M行了理論研究及算法改進,并將研究成果應(yīng)用于SCR脫硝系統(tǒng)。具體工作如下:針對脫硝系統(tǒng)的非線性、大時滯和時變等特性,根據(jù)Smith預(yù)估器補償滯后的特性和滑�？刂启敯粜詮姷奶攸c,將滑模控制器與Smith預(yù)估器結(jié)合起來應(yīng)用于SCR脫硝系統(tǒng)。針對滑�？刂破鞯亩墩�,將其看作噪聲,采用低通濾波器進行濾波,得到平滑的控制信號,然而滑模控制的魯棒性與切換增益相關(guān),切換增益越大時魯棒性越強,上述方法在外部擾動大于切換增益時,存在穩(wěn)態(tài)誤差,采用積分滑模面解決這一問題。針對積分滑模面在初始誤差較大時造成系統(tǒng)超調(diào)大的問題,采用時變積分滑模面,使系統(tǒng)狀態(tài)從初始時刻位于滑模面,然而仍無法減小超調(diào),因此提出條件積分型滑模面改進積分滑模面,使積分作用僅發(fā)生在滑模面附近的邊界層內(nèi),從而避免了初始誤差的影響,保證了跟蹤精度,獲得了較好的暫態(tài)性能,針對實際系統(tǒng)不確定性上界未知的情況,采用自適應(yīng)律自動調(diào)節(jié)切換增益,設(shè)計了基于Smith預(yù)估的自適應(yīng)條件積分型滑模控制器,并通過仿真驗證了該控制器的魯棒性。
[Abstract]:The nonlinear, time-delay and time-varying characteristics of SCR denitrification system of thermal power unit make the actual control more difficult. Recently, with the deterioration of atmospheric environment, the emission standard of nitrogen oxides for thermal power units has become more stringent, and the control performance of SCR denitrification system is also higher, so it is necessary to find a control algorithm with good performance. Since the sliding mode control was proposed, because of its strong robustness and good effect in nonlinear and time-varying system control, sliding mode control has been widely concerned and has been successfully used in robots, aerospace and other fields. Based on the retrofit of denitrification system in Datang Luoyang Shuangyuan Thermal Power Plant, the characteristics of denitrification system and the problems existing in the control of denitrification system at present are analyzed in this paper. Then, from the point of view of the combination of theory and application, the performance and buffeting of sliding mode control are studied theoretically and the algorithm is improved, and the research results are applied to SCR denitrification system. The concrete work is as follows: according to the nonlinear, large time delay and time varying characteristics of denitrification system, according to the characteristics of compensation lag of Smith predictor and strong robustness of sliding mode control, The sliding mode controller and Smith predictor are combined to apply to SCR denitrification system. Aiming at the buffeting of sliding mode controller, it is regarded as noise, and a smooth control signal is obtained by using low pass filter to obtain smooth control signal. however, the robustness of sliding mode control is related to switching gain, and the larger the switching gain is, the stronger the robustness is. When the external disturbance is larger than the switching gain, there is a steady-state error in the above method, and the integral sliding mode surface is used to solve this problem. In order to solve the problem that the system overshoot is caused by the initial error of the integral sliding mode surface, the time-varying integral sliding mode surface is adopted so that the state of the system is located on the sliding mode surface from the initial time, but it is still impossible to reduce the overshoot. Therefore, the conditional integral sliding mode surface is proposed to improve the integral sliding mode surface, so that the integral action only occurs in the boundary layer near the sliding mode surface, thus avoiding the influence of the initial error, ensuring the tracking accuracy and obtaining better transient performance. In order to solve the problem that the upper bound of the uncertainty of the actual system is unknown, the adaptive conditional integral sliding mode controller based on Smith prediction is designed by using the adaptive law to automatically adjust the switching gain, and the robustness of the controller is verified by simulation.
【學(xué)位授予單位】：華北電力大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TP273;TM621

【參考文獻】

相關(guān)期刊論文 前10條

1 管永生;;去產(chǎn)能背景下的電煤漲價[J];中國電力企業(yè)管理;2016年19期

2 周健;胡旦華;朱文欽;王禮偉;陳挺;;CEMS系統(tǒng)原理及其在電廠中的應(yīng)用分析[J];電工技術(shù);2016年04期

3 姜家國;郭為民;劉延泉;唐耀華;;選擇性催化還原脫硝系統(tǒng)Smith預(yù)估自抗擾控制[J];熱力發(fā)電;2016年01期

4 鄭志勇;黃達;;基于先進控制技術(shù)的660MW超超臨界機組SCR脫硝控制方案[J];江西電力;2014年05期

5 周長城;金保f;朱孝強;沈凱;徐海濤;;自適應(yīng)模糊方法在煙氣脫硝噴氨量控制系統(tǒng)中的應(yīng)用[J];環(huán)境工程;2014年S1期

6 李剛;胡森;武寶會;;基于模糊自適應(yīng)Smith的SCR噴氨量串級控制系統(tǒng)[J];熱力發(fā)電;2014年08期

7 蔣穎俊;;600 MW超臨界機組SCR脫硝優(yōu)化系統(tǒng)控制[J];能源研究與利用;2014年04期

8 潘楊;崔懷勝;賈慶巖;劉剛;;基于變Mole比方式的1000MW超超臨界機組脫硝控制策略優(yōu)化與應(yīng)用[J];湖北電力;2014年06期

9 馬雙忱;郭蒙;宋卉卉;陳公達;楊潔紅;藏斌;李釗;;選擇性催化還原工藝中硫酸氫銨形成機理及影響因素[J];熱力發(fā)電;2014年02期

10 錢榮榮;駱敏舟;趙江海;葉曉東;;永磁同步電動機新型自適應(yīng)滑�？刂芠J];控制理論與應(yīng)用;2013年11期

相關(guān)博士學(xué)位論文 前1條

1 李鵬;傳統(tǒng)和高階滑�？刂蒲芯考捌鋺�(yīng)用[D];國防科學(xué)技術(shù)大學(xué);2011年

相關(guān)碩士學(xué)位論文 前5條

1 劉琦;基于DCS的火電廠脫硝工程控制系統(tǒng)的設(shè)計[D];太原科技大學(xué);2015年

2 楊超;脫硝裝置控制系統(tǒng)的整合和優(yōu)化[D];浙江大學(xué);2015年

3 王婷;模型預(yù)測控制在電廠選擇性催化還原脫硝系統(tǒng)中的應(yīng)用研究[D];浙江大學(xué);2015年

4 于文清;SCR法煙氣脫硝系統(tǒng)的控制策略在火電廠中的應(yīng)用[D];華北電力大學(xué);2012年

5 吳阿峰;700MW電廠煙氣脫硝技術(shù)的技術(shù)經(jīng)濟分析及NOx生成模擬[D];重慶大學(xué);2006年

，

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