外文翻譯----燃?xì)忮仩t控制系統(tǒng)

1、.附錄2燃?xì)忮仩t控制系統(tǒng)鍋爐燃燒系統(tǒng)是使燃料燃燒所產(chǎn)生的熱量， 適應(yīng)蒸汽負(fù)荷的需要， 同時(shí)還要保證經(jīng)濟(jì)燃燒和鍋爐安全運(yùn)行。首先， 要維持蒸汽母管的蒸汽壓力不變， 采用雙交叉限幅控制， 使鍋爐系統(tǒng)無論在負(fù)荷上升或下降時(shí)都能滿足“負(fù)荷增加時(shí)，先增加空氣量， 后增加燃料量； 負(fù)荷減少時(shí)，先減少燃料量， 后減少空氣量”， 以使鍋爐燃燒持續(xù)保持在無黑煙狀態(tài)； 其次， 保持鍋爐燃燒的經(jīng)濟(jì)性， 以達(dá)到最小的熱量損失和最大的燃燒效率； 最后， 始終維持爐膛負(fù)壓在一定范圍內(nèi)，以使燃燒工況、鍋爐房工作條件、鍋爐的維護(hù)及安全運(yùn)行都最有利。在工業(yè)鍋爐燃燒過程中， 用常規(guī)儀表進(jìn)行控制， 存在滯后、間歇調(diào)節(jié)、煙氣中氧含量

2、超過給定值、低負(fù)荷和煙氣溫度過低等問題。采用PLC 對鍋爐進(jìn)行控制時(shí)， 由于它的運(yùn)算速度快、精度高、準(zhǔn)確可靠， 可適應(yīng)復(fù)雜的、難于處理的控制系統(tǒng)。因而，可以解決以上由常規(guī)儀表控制難以解決的問題。負(fù)荷調(diào)節(jié)是以蒸汽壓力為主調(diào)參數(shù)， 蒸汽流量為前饋信號(hào)， 并考慮鼓風(fēng)量的影響而進(jìn)行的復(fù)雜PID 串級(jí)調(diào)節(jié)； 氧量調(diào)節(jié)通過氧量信號(hào)、蒸汽流量及鼓風(fēng)量來調(diào)節(jié)爐排電機(jī)轉(zhuǎn)速， 控制給煤量； 爐膛壓力調(diào)節(jié)以爐膛壓力為主調(diào)參數(shù)， 鼓風(fēng)量為前饋信號(hào)進(jìn)行P I 調(diào)節(jié)， 控制引風(fēng)機(jī)轉(zhuǎn)速; 在鍋爐燃燒控制中，對蒸汽壓力極高進(jìn)行越限報(bào)警及聯(lián)鎖控制： 即當(dāng)蒸汽壓力高于報(bào)警上限時(shí)， 產(chǎn)生上限越限聲光報(bào)警， 當(dāng)蒸汽壓力高于報(bào)警上上限

3、時(shí)， 除進(jìn)行越限聲光報(bào)警外，PLC 發(fā)出聯(lián)鎖控制信號(hào)， 強(qiáng)制鼓風(fēng)電機(jī)、引風(fēng)電機(jī)及爐排電機(jī)停機(jī)， 鍋爐緊急停爐， 以保證安全生產(chǎn)。系統(tǒng)硬件組成根據(jù)工藝特點(diǎn)及鍋爐的位置分布， 選擇IPC 和PLC 組成基于IPC- PLC 的三級(jí)DCS 監(jiān)控系統(tǒng)， 整個(gè)控制系統(tǒng)的組成圖。用三臺(tái)西門子S7- 300 系列PLC 分別控制三臺(tái)鍋爐， 安裝在中控室。PLC 用西門子的Step7 軟件進(jìn)行硬件組態(tài), 所有的PID 控制、聯(lián)鎖保護(hù)、開關(guān)量控制均在PLC 上實(shí)現(xiàn)。三臺(tái)PLC 通過以太網(wǎng)與上位工控機(jī)相連, 將現(xiàn)場采集的數(shù)據(jù)傳給上位工控機(jī), 并接收上位工控機(jī)的各種數(shù)據(jù)和控制命令。最上層設(shè)四臺(tái)工控機(jī), 也全部安裝在

4、中控室。其中三臺(tái)作為并行運(yùn)行的操作員站, 另一臺(tái)作為工程師站。上位工控機(jī)采用西門子的WinCC 軟件進(jìn)行人機(jī)界面的編制, 并通過人機(jī)界面對下位機(jī)的所有參數(shù)進(jìn)行遠(yuǎn)程設(shè)置和調(diào)整, 監(jiān)控所有設(shè)備的運(yùn)行情況。用WinCC 全局腳本實(shí)現(xiàn)模糊控制算法、鍋爐效率在線實(shí)時(shí)計(jì)算和風(fēng)煤比自尋優(yōu)算法等。另選用一個(gè)分布式I/O 模塊ET200M作為DP 從站, 通PROFIBUS- DP 現(xiàn)場總線與PLC 相連, 用來控制三臺(tái)鍋爐共用的附屬設(shè)備, 如: 水處理設(shè)備、補(bǔ)水設(shè)備等, 實(shí)現(xiàn)恒壓補(bǔ)水控制等。另外為了節(jié)能, 所有的風(fēng)機(jī)、水泵和電機(jī)均采用變頻控制, 變頻器選用富士通用變頻器。系統(tǒng)軟件設(shè)計(jì)由于系統(tǒng)實(shí)現(xiàn)功能較多,可靠

5、性要求高,所以軟件設(shè)計(jì)的難度和工作量也變得非常之大。本系統(tǒng)軟件采用模塊化方法設(shè)計(jì),整個(gè)任務(wù)分成若干個(gè)子任務(wù),每個(gè)模塊及其功能如下:(1) 初始化模塊。對所有使用的中間繼電器M、定時(shí)器T 和數(shù)據(jù)寄存器D 進(jìn)行初始化處理。對一些需要初值的參量賦值。(2) TD200 人機(jī)界面模塊。該模塊主要處理人機(jī)界面的智能顯示邏輯和對TD200 組態(tài)信息的使用。(3) 增管、減管判斷模塊。判斷何時(shí)增減電熱管及相關(guān)邏輯。(4) 電熱管投入和退出邏輯模塊。根據(jù)增減電熱管的判斷結(jié)果和目前電熱管的運(yùn)行狀態(tài),來決定哪一組電熱管應(yīng)該投入或退出。該邏輯在各子程序中完成。(5) 電熱管各種工作模式模塊。根據(jù)工作模式的選擇,系統(tǒng)

6、可分別進(jìn)入常規(guī)模式、經(jīng)濟(jì)模式及半經(jīng)濟(jì)模式工作。要做到正確的工作模式選擇,加熱管工作個(gè)數(shù)的確定非常重要,S7 - 200 PLC 中沒有SUM 指令,所以要建立一個(gè)存儲(chǔ)單元,每組電熱管通電和退出時(shí),分別對該存儲(chǔ)單元進(jìn)行加1 和減1 運(yùn)算,這樣存儲(chǔ)單元中的值就是加熱管工作的個(gè)數(shù)。(6) 輸出處理模塊。(7) 報(bào)警處理模塊。處理各種報(bào)警信息。1 汽包水位調(diào)節(jié)在負(fù)荷比較穩(wěn)定的情況下, 汽包水位一般采用典型的三沖量水位調(diào)節(jié)即可獲得較為理想的控制效果。但是, 在負(fù)荷變化較大的情況下,采用上述典型控制算法效果不理想, 水位和蒸汽壓力經(jīng)常出現(xiàn)報(bào)警, 根本無法使系統(tǒng)穩(wěn)定工作, 甚至無法實(shí)現(xiàn)自動(dòng)控制。鍋爐負(fù)荷就屬

7、于這種情況。因此, 我們在典型的三沖量控制中增加了一些補(bǔ)償算法, 并對測量參數(shù)進(jìn)行了適當(dāng)處理, 現(xiàn)場實(shí)際投運(yùn)后效果很好。由于水位穩(wěn)定, 使得蒸汽壓力自動(dòng)控制成為可能,從而解決了因蒸汽壓力過低進(jìn)口設(shè)備無法正常運(yùn)行的難題。另外, 在軟件中對操作量輸出進(jìn)行了補(bǔ)(運(yùn)算, 即增加了輸出限幅, 但該限幅是在線自整定的, 即克服了給水閥動(dòng)作頻繁, 閥體容易磨損的問題, 延長了電動(dòng)調(diào)節(jié)閥的使用壽命, 又解決了由于輸出限幅造成的在蒸汽流量突然增大時(shí), 水位調(diào)節(jié)速度慢的問題。2 爐膛負(fù)壓調(diào)節(jié)爐膛負(fù)壓調(diào)節(jié)采用前饋回路以克服送風(fēng)量變化造成的干擾, 用反饋回路克服偏差, 控制引風(fēng)機(jī)的轉(zhuǎn)速, 達(dá)到改變風(fēng)量的大小, 使?fàn)t膛

8、負(fù)壓維持在給定范圍內(nèi)。在引風(fēng)輸出中也增加了輸出限幅以減少引風(fēng)機(jī)頻繁動(dòng)作。同樣, 由于負(fù)荷變化較大, 也增加了限幅在線自整定算法。3 蒸汽壓力及風(fēng)煤配比調(diào)節(jié)這是一個(gè)多回路前饋調(diào)節(jié)系統(tǒng), 蒸汽壓力PID 調(diào)節(jié)的輸出加上修正算法作為風(fēng)量調(diào)節(jié)的給定, 而風(fēng)量PID 調(diào)節(jié)的輸出控制鼓風(fēng)機(jī)的變頻調(diào)速, 同時(shí)又通過比值調(diào)節(jié)控制爐排電機(jī)的變頻調(diào)速, 從而改變送風(fēng)量和送煤量。為減少在蒸汽負(fù)荷變化時(shí)對蒸汽壓力的擾動(dòng), 引進(jìn)了蒸汽流量作前饋調(diào)節(jié)。在這個(gè)調(diào)節(jié)回路中, 不但增加了爐排輸出限幅的在線自整定, 而且當(dāng)蒸汽流量突然變化時(shí), 還增加了風(fēng)煤配比的在線自整定, 用來既保證在蒸汽流量突然增大時(shí)仍能保證蒸汽壓力大于7k

9、g, 又能保證在蒸汽流量突然減少時(shí)蒸汽壓力不會(huì)超限, 使系統(tǒng)保持穩(wěn)定, 同時(shí)還達(dá)到了既節(jié)能又不冒黑煙的效果。出水溫度控制系統(tǒng)主要實(shí)現(xiàn)根據(jù)室內(nèi)外溫度測量值和室外風(fēng)速, 調(diào)節(jié)給煤量、鼓風(fēng)量和引風(fēng)量, 從而實(shí)現(xiàn)按需供熱、安全經(jīng)濟(jì)環(huán)保運(yùn)行的目的。出水溫設(shè)定值隨室外環(huán)境溫度的變化自動(dòng)調(diào)整。給煤量根據(jù)出水溫度測量值與給定值之間的偏差, 采用模糊控制算法進(jìn)行調(diào)整, 以達(dá)到快速調(diào)整出水溫度的目的。同時(shí), 根據(jù)鍋爐效率實(shí)時(shí)在線計(jì)算的結(jié)果, 對給煤量進(jìn)行微調(diào), 從而保證鍋爐的經(jīng)濟(jì)燃燒。鼓風(fēng)量根據(jù)給煤量和風(fēng)煤比的變化, 采用常規(guī)PID 算法進(jìn)行調(diào)整, 實(shí)現(xiàn)比值控制, 達(dá)到完全燃燒、經(jīng)濟(jì)燃燒的目的。其中根據(jù)能量平衡理

10、論, 采用自尋優(yōu)算法對風(fēng)煤比進(jìn)行在線實(shí)時(shí)調(diào)整, 使燃料與空氣始終保持最佳的配比, 實(shí)現(xiàn)燃料的完全燃燒。引風(fēng)量根據(jù)爐膛負(fù)壓測量值, 采用常規(guī)PID 算法進(jìn)行調(diào)整, 并將鼓風(fēng)量作為前饋量, 實(shí)現(xiàn)前饋反饋控制, 以保持爐膛的微負(fù)壓狀態(tài), 確保鍋爐安全運(yùn)行。參考文獻(xiàn)：計(jì)算機(jī)應(yīng)用. 2002.07附錄3Boiler Control SystemBoiler combustion system is produced by fuel combustion heat to adapt to the needs of steam load, we need to ensure that the economi

11、c boiler combustion and safe operation. First, the mother of steam to maintain the steam pressure remains unchanged, a dual-limiting control, the boiler system in load increased or decreased at will meet the "load increased, to increase the volume of air, after the increase in fuel; reduce the

12、load , To reduce the amount of fuel, reducing air after ", so that the boiler combustion in the absence of black smoke continued to maintain state and secondly, to maintain the economic boiler combustion, so as to minimize heat loss and the largest combustion efficiency; Finally, always maintai

13、n Furnace negative pressure in a certain range, so that the burning conditions, working conditions boiler room, boiler maintenance and safe operation are the most favourable. In the industrial boiler combustion process, the use of conventional instrumentation control, there stagnant, intermittent co

14、nditioning, oxygen content in the flue gas over a given value, low load and low temperature gas, and other issues. PLC used to control the boiler, because of its high speed, high precision, accurate and reliable, can adapt to complex and difficult to deal with the control system. As a result, more t

15、han can be solved by conventional instrumentation control difficult issues. . Load regulation is the main tune parameters of steam pressure, steam flow for the feed-forward signal, and to consider the impact of the blast in the complex cascade PID regulation; oxygen through the oxygen signal conditi

16、oning, and the blast of steam flow to regulate Grate Motor speed, control the volume of coal, furnace pressure adjusted to the pressure chamber for the main parameters of the blast before the Fed signals PI regulation, with fan speed control in the boiler combustion control, the high pressure steam

17、to the limit and alarm Interlocking control: that is, when the steam pressure higher than the warning limit, a ceiling of the limited sound and light alarm, when the steam pressure higher than the alarm on the limit, in addition to the restrictions of sound and light alarm, PLC issued interlock cont

18、rol signals, forced the dark Feng Motors, with winds of Electrical and grate the electrical shutdown, emergency boiler Boilers off Load, to ensure production safety. System hardware According to characteristics of the boiler and distribution, select PLC IPC and IPC-PLC-based components of the three

19、DCS control system, the composition of the entire control system plans. With three Siemens S7-300 series PLC control were three boilers, installed in the control room. PLC with Siemens Step7 software to the hardware configuration, all of the PID control, interlocking protection, volume control switc

20、h in the PLC are to achieve. PLC via Ethernet and three top industrial computer connected to the data collected at the top IPC transmission and reception of the top industrial computer data and control commands. The top four for IPC, also installed in the control room. Three of them as a parallel op

21、eration of the operator station, another station as an engineer. Upper IPC use the Siemens WinCC human-computer interface software for the establishment, and through human-computer interface for the next crew of all the parameters for remote settings and adjustments, monitor the operation of all equ

22、ipment. WinCC script with the overall realization of fuzzy control algorithms, boiler efficiency of coal-line real-time calculation and wind than self-optimizing algorithm. Another choice of a distributed I / O modules ET200M from the station as the DP, through PROFIBUS-DP fieldbus connected with th

23、e PLC, the three boilers used to control the sharing of ancillary equipment, such as: water treatment equipment, water supplement equipment, and constant Water pressure control. In addition to energy conservation, all the fans, pumps and motors are used Frequency Control, Drives Fujitsu General opti

24、onal converter. System Software Design As more functional systems, high reliability requirements, software Design and the difficulty of the workload has become very large. The mining system software Modular design approach used, the whole mission is divided into several sub-tasks, each Module and it

25、s functions are as follows: (1) to initialize module. The use of all the intermediate relay M, set When T-D registers and data processing to initialize. The need for some To the initial parameter assignment. (2) TD200 human-computer interface module. The module is primarily concerned with human-comp

26、uter Intelligence shows that the interface logic and configuration information on the use of TD200. (3) by tube, by judgement of the module. Determine when changes in the electric and Related logic. (4) electric input and exit of logic modules. According to increase or decrease in electric And the r

27、esults of the judgement of the electric current running state, to decide which Electric Group should join or withdraw from the tube. The logic in all routines in the End 10%. (5) of various electric mode module. According to the mode of work Choice, the system can be entered conventional model, econ

28、omic model and semi-economic model Working. To achieve the correct mode of choice, a heating pipe work Determine the number of very important, S7 - 200 PLC did not SUM command, Therefore, to build a storage unit, each of electric power in and out, The storage unit were carried out by a Canadian and

29、an operator, this single store Yuan in value is the number of heating pipe work. (6) export processing module. (7) alarm processing module. Dealing with all kinds of warning messages. 1 drum level adjustment Load in the relatively stable situation, the general drum water level typical of the three-v

30、olume water level regulation can be better control. However, the larger changes in the load cases, the typical control algorithms are not effective, water and steam pressure often the police simply can not make the system stability, or even impossible to achieve control. Boiler load on the case. The

31、refore, we in a typical three-volume control has been added to some compensation algorithm, and measurement parameters are properly addressed and put into operation at the scene after the actual good effect. As the water level stability, makes it possible to control steam pressure, so as to solve th

32、e steam pressure is too low for imported equipment can not be normal operation of the problems. In addition, the software exports in the operation of a meeting (computing, representing an increase of the output limiting, but it is limiting on-line self-tuning, that is to overcome the frequent moves

33、to the valves, valve body to wear the issue of extension of the Electric control valve life, to solve the limiting output due to the sudden increase in the flow of steam, the water level of slow adjustment problems. 2 vacuum furnace regulation Vacuum Furnace regulating use of feed-forward loop to ov

34、ercome the air supply of changes in the disruption caused by feedback loop to overcome bias, with fan speed control, to change the size of the wind, so that the furnace to maintain negative pressure in a given area. With the wind in output also increased by limiting output to reduce Fan frequent mov

35、es. Similarly, the larger load changes, also increased by limiting on-line self-tuning algorithm. 3 steam pressure and oxy-acetylene ratio adjustment This is a multi-loop feedforward-conditioning systems, steam pressure PID regulator added that the output of wind as a method of adjusting a given, bu

36、t the wind of P ID-conditioning control the output of the blower Frequency Control, but also by adjusting the ratio of motor control Grate The Frequency Control, in order to change the air supply and delivery of coal. To reduce the load of steam when the steam pressure in the disturbance, the introd

37、uction of steam flow for feed-forward regulation. In this regulation circuit, will not only increase the output limiting Grate the online self-tuning, and when the steam flow suddenly changes, also increased the oxy-acetylene ratio of online self-tuning, both to ensure that a sudden increase in the

38、flow of steam Can guarantee that when the steam pressure is greater than 7 kg, can guarantee that a sudden reduction in the flow of steam when the steam pressure will not be overrun, allowing the system to maintain stability, also reached both energy conservation without the effect of black smoke.Wa

39、ter leakage temperature control system: mainly realizes acts according to the indoor outside temperature observed value and the outdoor wind speed, adjusts for the coal amount, the drum amount of wind and directs the amount of wind, thus realizes on demand to heat, the security economical environmental protection movement goal. Leaves the water temperature setting value along with the outdoor ambient temperature change automati