【正文】 鐵嶺電廠 3機(jī)組汽包水位控制系統(tǒng)設(shè)計(jì) I 摘 要 本文針對(duì)給水調(diào)節(jié)系統(tǒng)的被控對(duì)象動(dòng)態(tài)特性、熱工測(cè)量信號(hào)、調(diào)節(jié)機(jī)構(gòu)特性，分析了三沖量給水控制系統(tǒng)的結(jié)構(gòu)及工作原理，實(shí)現(xiàn)單元制給水全程控制系統(tǒng)應(yīng)考慮的問(wèn)題及控制方案。 300MW 機(jī)組汽包水位系統(tǒng)的構(gòu)成原理和控制功能，系統(tǒng)的總體結(jié)構(gòu)、工作原理、控制過(guò)程、系統(tǒng)切換方式、控制邏輯、調(diào)試及參數(shù)整定原則 。 300MW 機(jī)組汽包水位控制系統(tǒng)，采用兩臺(tái)汽動(dòng)給水泵和 1 臺(tái)啟動(dòng) /備用電動(dòng)給水泵供水?？刂品桨覆捎脝?/三沖量結(jié)合，在低負(fù)荷時(shí)采用單沖量控制，在高負(fù)荷時(shí)采用三沖量控制 ,實(shí)現(xiàn)了全程給水自動(dòng)控制。該系統(tǒng)的結(jié)構(gòu)設(shè)計(jì)合理、功 能完善、使用可靠，實(shí)現(xiàn)了啟動(dòng)初期鍋爐進(jìn)水直至停機(jī)鍋爐放水全工況下汽包水位的控制，大大的減少了運(yùn)行人員，達(dá)到了減員增效的目的，具有積極的推廣應(yīng)用價(jià)值。 關(guān)鍵詞 汽包水位控制，單沖量，三沖量，全程給水自動(dòng)控制 沈陽(yáng)工程學(xué)院畢業(yè)設(shè)計(jì)（論文） II Abstract According to the water supply control system of the controlled object dynamic characteristic, thermal measurement signal, adjusting mechanism characteristics, analyzed three impulse feedwater control system structure and working principle, implementation unit feedwater control system should consider the problem and control fullrange feedwater control system of the position principle and control function, system structure, working principle, process control, system switching mode, control logic, debugging and parameters setting principle. 300MW unit boiler feedwater control system, using two steam feed pump and 1startup / standby electric feedwater pump. Control scheme using single / three impulse bination, when the low load using a single impulse control, in the high load using three impulse control, to achieve the full automatic feed water control. The system design and reasonable structure, perfect function, reliable use, realize the startup stage of boiler water to stop water under all operating conditions of boiler drum water level control, greatly reducing the operating personnel, achieved the goal of synergism of depletion of numbers, has positive popularization application value. Key Words Boiler feedwater control， Single impulse， Three impulse， All range feedwater automatic control 鐵嶺電廠 3機(jī)組汽包水位控制系統(tǒng)設(shè)計(jì) III 目 錄 摘要 .................................................................................................................................................. I Abstract ..........................................................................................................................................II 1 引言 ........................................................................................................................................ 1 課題背景及選題意義 ..................................................................................................... 1 自動(dòng)控制技術(shù)在電廠的應(yīng)用 .................................................................................. 1 火電廠自動(dòng)化的內(nèi)容 ................................................................................................... 1 本設(shè)計(jì)研究的主要內(nèi)容 ................................................................................................. 2 火電廠基本生產(chǎn)過(guò)程 ..................................................................................................... 3 汽包水位控制系統(tǒng)簡(jiǎn)介 ...................................................................................................... 4 2 給水被控對(duì)象的動(dòng)態(tài)特性 ......................................................................................................... 6 汽包水位的動(dòng)態(tài)特性 .......................................................................................................... 6 各種擾動(dòng)下水 位變化的動(dòng)態(tài)特性 ....................................................................................... 7 給水流量擾動(dòng)下對(duì)象的動(dòng)態(tài)特性 ............................................................................... 7 蒸汽流量擾動(dòng)下對(duì)象的動(dòng)態(tài)特性 ............................................................................... 8 爐膛熱負(fù)荷擾動(dòng)下對(duì)象的動(dòng)態(tài)特性 ........................................................................... 9 3 鐵嶺電廠 3 機(jī)組汽包水位控制系統(tǒng)設(shè)計(jì) .............................................................................. 10 給水控制系統(tǒng)總體方案的確定 ........................................................................................ 10 給水控制系統(tǒng)設(shè)計(jì) ............................................................................................................ 10 汽包水位控制系統(tǒng)基本任務(wù) ..................................................................................... 10 給水控制系統(tǒng)原理圖 ................................................................................................. 11 汽包水位控制系統(tǒng)控制策略設(shè)計(jì) .................................................................................... 11 汽包的工作原理 ......................................................................................................... 12 影響汽包水位變化的因素 ......................................................................................... 12 汽包水位的測(cè)量 ......................................................................................................... 13 測(cè)量信號(hào)的自動(dòng)校正 ................................................................................................... 14 水位信號(hào)的壓力校正 ............................................................................................ 14 過(guò)熱蒸汽流量信號(hào)的壓力、溫度校正 ................................................................ 15 給水流量信號(hào)的溫度校正 .................................................................................... 15 4 鐵嶺 電廠 3 機(jī)組汽包水位控制 SAMA 圖分析 ............................................................... 17 給水全程控制的關(guān)鍵問(wèn)題 ........................................................................................... 17 控制回路 SAMA 圖分析 ............................................................................................. 17 熱工信 號(hào)的測(cè)量 .................................................................................................... 17 旁路給水控制 ........................................................................................................ 20 電動(dòng)泵的控制 ............................................................................................................. 20