第46卷第12期中國電力Vol. 46, No. 122013年12月ELECTRIC POWERDec.2013發(fā)電基于DCS系統(tǒng)變頻循環(huán)水泵節(jié)能自動(dòng)控制張利,張宇,劉衛(wèi)平,甘智勇,王建(天津市電力公司電力科學(xué)研究院,天津300384)摘要:以運(yùn)行機(jī)組DCS系統(tǒng)為基礎(chǔ)，介紹了一種變頻循環(huán)水泵節(jié)能自動(dòng)控制的實(shí)現(xiàn)方法。從節(jié)能自動(dòng)控制的理論和原理出發(fā).通過實(shí)時(shí)計(jì)算凝汽器的運(yùn)行清潔系數(shù)，采用循環(huán)重復(fù)計(jì)算法求取凝汽器最佳真空及對(duì)應(yīng)的變頻循環(huán)水泵運(yùn)行方式,對(duì)比分析并確定節(jié)能自動(dòng)控制的實(shí)現(xiàn)方案，詳細(xì)闡述了建立節(jié)能自動(dòng)控制系統(tǒng)的注意事項(xiàng)以及實(shí)現(xiàn)過程中遇到的問題及解決方法，以某電廠330 MW熱電聯(lián)產(chǎn)機(jī)組為例進(jìn)行了測(cè)算，實(shí)施變頻循環(huán)水泵節(jié)能自動(dòng)控制后年可節(jié)電376.16萬kW.h。關(guān)鍵詞:火力發(fā)電廠: DCS系統(tǒng);變頻循環(huán)水泵;節(jié)能自動(dòng)控制系統(tǒng)中圖分類號(hào): TK264.1文獻(xiàn)標(biāo)志碼: B文章編號(hào): 1004-9649(2013)12-0059-030引言式中:Q為冷卻水流量，kg/s;cp為冷卻水平均溫度下的比熱容，J/(kg-K); tr 為冷卻水出水溫循環(huán)水系統(tǒng)是火力發(fā)電機(jī)組重要的熱力系統(tǒng)度，c; 1為冷卻水進(jìn)水溫度，C; A為凝汽器有之一，循環(huán)水泵是電廠最主要的輔機(jī)耗電大戶,效換熱面積，m;LMTD為凝汽器對(duì)數(shù)平均溫提高循環(huán)水系統(tǒng)的運(yùn)行經(jīng)濟(jì)性長(zhǎng)期以來是廣大節(jié)差, C; K。為基本傳熱系數(shù)，W/(m2.9C); B,為冷能工作者研究的主要方向之- 1141。 近年來，隨著卻水進(jìn)水溫度修正系數(shù); B.為冷卻管管材和壁厚變頻調(diào)速技術(shù)的發(fā)展，變頻調(diào)速的可靠性不斷加修正系數(shù)。強(qiáng)，初期投資成本不斷降低，使得高壓變頻調(diào)速1.2 最佳真空及循環(huán)水泵運(yùn)行方式的計(jì)算技術(shù)在火電廠循環(huán)水泵上的應(yīng)用越來越廣泛5，循采用循環(huán)重復(fù)計(jì)算法求取凝汽器最佳真空及環(huán)水泵將逐步進(jìn)入變頻時(shí)代。對(duì)應(yīng)的循環(huán)水泵運(yùn)行方式，具體計(jì)算流程如下:變頻循環(huán)水泵可以實(shí)現(xiàn)循環(huán)水泵轉(zhuǎn)速和循環(huán)①假設(shè)循環(huán)水泵變頻器輸出反饋信號(hào)x，計(jì)算該水流量的連續(xù)性調(diào)節(jié)，從而實(shí)現(xiàn)凝汽器最佳真空變頻轉(zhuǎn)速下循環(huán)水泵耗功w。和循環(huán)水流量Q。的精確控制，同時(shí)為循環(huán)水泵的節(jié)能自動(dòng)控制提②結(jié)合運(yùn)行清潔系數(shù)計(jì)算過程中得到的當(dāng)前運(yùn)行供了前提和基礎(chǔ)。因此，優(yōu)化變頻循環(huán)水泵運(yùn)行工況下凝汽器熱負(fù)荷和運(yùn)行清潔系數(shù)B.依次計(jì)算控制方式，建立變頻循環(huán)水泵節(jié)能自動(dòng)控制系統(tǒng)，循環(huán)水溫升Ot、凝汽器端差δ和蒸汽凝結(jié)溫度t。o充分挖掘變頻循環(huán)水泵的節(jié)能潛力，將成為未來③由蒸汽凝結(jié)溫度I,計(jì)算假設(shè)循環(huán)水泵變頻器輸循環(huán)水系統(tǒng)節(jié)能工作的重點(diǎn)和發(fā)展方向。出反饋時(shí)凝汽器壓力p.,得到該真空狀態(tài)下對(duì)汽輪機(jī)功率的影響△W。④計(jì)算oW與w,的差值，1節(jié) 能自動(dòng)控制的實(shí)時(shí)計(jì)算當(dāng)兩者的差值最大時(shí)(OW- -Wp)m,此時(shí)對(duì)應(yīng)的凝汽器壓力即為機(jī)組在當(dāng)前運(yùn)行工況下的最佳真空，1.1凝汽器實(shí)時(shí)運(yùn)行清潔系數(shù)的計(jì)算假設(shè)循環(huán)水泵變頻器輸出反饋即為最佳真空對(duì)應(yīng)凝汽器的運(yùn)行清潔系數(shù)綜合反映了凝汽器的的循環(huán)水泵運(yùn)行方式。最佳真空及循環(huán)水泵運(yùn)行臟污程度、管束布置、不凝結(jié)氣體聚集程度6,實(shí)方式的計(jì)算過程如圖1所示。時(shí)計(jì)算出凝汽器的運(yùn)行清潔系數(shù)，可以得到凝汽器的實(shí)時(shí)性能。運(yùn)行清潔系數(shù)按照HEI公式計(jì)算2節(jié)能自動(dòng)控制實(shí)現(xiàn)方案比較Qxc,x(4-1)(1)B.-= A xLMTDxKoxXB,xBm為實(shí)現(xiàn)變頻循環(huán)水泵的節(jié)能自動(dòng)控制,有以收稿日期: 2013-09-28中國煤化工作者簡(jiǎn)介:張利(1985- -),男，湖北襄陽人，工程師，碩士，從事汽輪機(jī)節(jié)能.MYHCNM HGE-mail: zhanglihust@163.com發(fā)電中國電力第46卷參考文獻(xiàn):36(1): 6-11.7] 施維新.浮動(dòng)和接觸密封對(duì)軸系振動(dòng)影響的測(cè)試及分析J].中1]施維新.汽輪發(fā)電機(jī)組振動(dòng)及事故[M].北京:中國電力出版社,國電力,2004,37(2);11-16.1999:436- 457.SHI Weixin. Testing and analysis of impacts of floating and[2]張學(xué)延.汽輪發(fā)電機(jī)組振動(dòng)診斷[M].北京:中國電力出版社,contact sealings on shaft system vibration [J]. Electric Power,2008:199- 256.2004, 37(2): 11-16.3]陸頌元.汽輪發(fā)電機(jī)組振動(dòng)[M].北京:中國電力出版社,000:[8] 張學(xué)延，楊壽敏,張衛(wèi)軍,等.汽輪發(fā)電機(jī)組轉(zhuǎn)子材質(zhì)缺陷引起166-173.的振動(dòng)問題[J.中國電力,2010,43(5):38-42.[4] 施維新,石靜波.汽輪發(fā)電機(jī)組振動(dòng)及事故[M].北京:中國電ZHANG Xue-yan, YANG Shou-min, ZHANG Weijun, et al.力出版社,2008:290-302.Vibration problems caused by material defects of turbine-[5]寇勝利.汽輪發(fā)電機(jī)組的振動(dòng)及現(xiàn)場(chǎng)動(dòng)平衡[M].北京:中國電generator unit rotor []. Electric Power, 2010, 43(5): 38-42.力出版社,2007:106-118. .9]寇勝利.轉(zhuǎn)子活動(dòng)部件引起的振動(dòng)研究[J].中國電力,2003,36[6]陸頌元.大型機(jī)組動(dòng)靜碰磨的振動(dòng)特征及現(xiàn)場(chǎng)應(yīng)急處理方法(8):1-3.[小].中國電力,2003 ,36(1):6-11.KOU Shengli. Vibration of steam turbine arising from movingLU Songyuan. Vibration charateristics and on-site emergencyparts on rotor [I]. Eletric Power, 2003, 36(8): 1-3.trouble-shooting method of rubbing between moving and stationaryparts of steam turbine-generator units []. Electric Power, 2003,(責(zé)任編輯張燕)Analysis and Identification of Friction Vibration of Turbo-Generator UnitsYE Ze-ping, DAI Wei(The Commissioning and Test Istitute of Sichuan Electric Power Indutry, Chengdu 610072, China)Abstract: The axial and radial clearances of turbine- generator units are quite small. Therefore collision and friction will happen in the caseof diminishing axial or radial clearances between the rotating and the stationary parts, which will cause unit vibrations. In this paper, themechanism, occasion and location of the vibration caused by collision and friction are introduced. Through the analysis on the causes andcharacteristics of the axial and radial collision and friction, the methods for identifying the vibration under different conditions arepresented. Finally, measures to prevent the vibration in the manufacturing, installation, maintenance, startup and running of the units areput forward.Key words: steam turbine generator; cllision and friction between rotating and stationary parts; frictional vibration.++*+*+++++- +*++++*++*++*+*++(上接第61頁)LI Yong, CAO Zu-qing. The concept of condenser cleaning ratePower Equipment, 2012, 26(3): 183-185.and tet method []. Turbine Technlolgy, 1995, 37(2): 73-76.]李勇,曹祖慶.凝汽器清潔率的概念及測(cè)試方法[].汽輪機(jī)技術(shù),1995 ,37(2):73 -76.(責(zé)任編輯李秀平)DCS-Based Energy Saving Automatic Control on Variable-FrequencyCirculating-Water PumpZHANG Li, ZHANG Yu, LIU Wei-Ping, GAN Zhi-yong, WANG Jian(Tianjin Electric Power Research Institute, Tianjin 300384, China)Abstract: Based on the DCS system for operating units, a method to realize the automatic control on the energy saving of variablefrequency circulating water pump is introduced. From the viewpoint of automatic control theory, the optimal condenser vacuum and thecorresponding operation mode of the pump are obtained through the calculation of real-ime condenser clean cofficient with the repeatedcycle method. Then by comparison and analysis the implementation plan is determined for the energy- saving automatic control in whichthe matters needing atention in establishing the automatic control system as well as the igaee and snting in the implementation areproposed in details. Finlly, the calculation on a 330 MW cogeneration unit is condu中國煤化工、wer consumption ofthe pump will decrease by 3 761.6 MW . h after the automatic control is implemented.YHCNMHGKey words: thermal power plant; DCS system; variabl-frequency circulating water pump; energy-saving automatic control66