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1、<p><b>  附 錄</b></p><p><b>  附錄A 外文翻譯</b></p><p>  The Analysis on Related Problems of Temperaure-humidity Control for Monitoring System of Central Air-condition<

2、/p><p>  1 Introduction </p><p>  "Green building" focus on environmental protection, energy saving, efficient use of resources and materials, especially focus on requirements for air tem

3、perature, humidity, ventilation and cleanliness. Therefore, the use of air conditioning system is more widely. Air-conditioning control system involves many aspects, but more complex tasks to be achieved. It needs suppor

4、t of cold and heat. There are high-power air conditioning unit fan, but it's a great energy. Under the premise of meeting the r</p><p>  2 system's basic structure and working principle </p>&

5、lt;p>  Structure and composition of air-conditioning system generally include the sections: </p><p>  (1) Part of the new wind Air-conditioning system during operation to capture part of the outdoor fresh

6、 air (ie fresh air), this part of the fresh air to meet indoor staff required minimum fresh air volume, so air conditioning system of fresh air taken into the amount determined by air-conditioning system service uses and

7、 hygiene requirements. The new wind into the general population in the surrounding areas from pollution. These new wind into port and air conditioning systems and new air ducts i</p><p>  (2) Part of air pur

8、ification Air-conditioning system according to their different uses, purification of air in different ways. Therefore, in the air purification system has set an initial effect of a simple air filter cleaning system, but

9、 also set an initial effective air filter and air filter efficiency level of the general purification system, in addition to setting an initial efficiency air filters, one in the efficiency of air filters and a HEPA filt

10、er for three high-purification system fil</p><p>  (3) Part of the air heat, wet Air heating, humidification and cooling, dehumidification, will combine the process, known as the air conditioning system, hea

11、t, wet part. In the air to heat, wet processing, surface-air heat exchanger. Setting a new air intakes in the system, a return air as the air before the air heater in a heater; set before cooling dehumidification air hea

12、ter, known as the secondary air heater; set in air-conditioned room before sending outlet air heater, known as the three air</p><p>  (4) The section of air transportation and distribution and control Fans

13、 and air conditioning systems to send, return air pipe as part of air transport. Duct in the regulation of air valve, butterfly valve, damper, boot valve and air outlet such as points, control section. Air-conditioning s

14、ystem according to the different air resistance, set the number of fans are different, if the air conditioning system for a wind turbine set, the fans not only from the air role, the role was underway as a s</p>&

15、lt;p>  (5). cold and heat source of air conditioning system, Air conditioning systems used in the cold cold source is generally divided into natural and artificial sources of cold source. Natural cooling source gener

16、ally refers to ground water from deep wells, artificial cold source generally refers to the use of artificial refrigeration means available, which includes the vapor compression refrigeration, absorption refrigeration, a

17、nd steam jet refrigeration, and other means. Modern large-scale buildi</p><p>  Its working principle is when the ambient temperature is too high, the air conditioning system, through re-circulated to the in

18、door heat away so that the indoor temperature is maintained at a certain value. When the circulation of air through the fan coil, the high-temperature air through the cooling coil of aluminum metal prior to heat exchange

19、 coil of aluminum absorbs heat from the air, the air temperature decreases, and then the cycle of freezing air given away after Indoor. Chilled water coo</p><p>  3. central air conditioning system control p

20、roblems </p><p>  3.1 The characteristics of the controlled object </p><p>  Air-conditioning system control objects are mostly thermal objects, from the perspective of control, has the followin

21、g characteristics:</p><p>  (1)more disruptive For example, incoming solar radiation through windows, heat is a function of time, subject to weather conditions; outdoor air temperature, room temperature thr

22、ough the envelope on impact; through doors, windows, building cracks penetrated the outdoor air temperature impact; to change gas (or maintain a certain positive pressure room) adopted a new style, its temperature change

23、s have a direct impact on the room temperature. In addition, the electric heater (air heater) power s</p><p>  So much interference, so that air conditioning load in the larger context of change, and their l

24、ocation into the system, form, size and frequency of such magnitude, both with the construction of the structure (building thermal performance), use of different and different, even with air conditioning technology itsel

25、f. Should be considered in the design of air conditioning systems to minimize interference with or taking anti-jamming measures. Therefore, we can say that air conditioning project is </p><p>  (2) Multi-con

26、dition Air conditioning technology in the treatment process is highly seasonal. Year, at least into the winter season and summer transition. In recent years, distributed systems in the air conditioning system, air cond

27、itioning for multiple applications to create conditions favorable conditions. As the air conditioning system, diversification, operational management and control devices to become complicated. Therefore require operators

28、 to be in strict accordance with the energy-eff</p><p>  (3) temperature, humidity correlation Describe the state of the two main parameters of air temperature and humidity as they are not completely indepen

29、dent of the two variables.When the relative humidity changes will cause humidification (or dehumidification) action, the results will lead to temperature fluctuations; and temperature changes, so indoor air vapor saturat

30、ion pressure, the absolute moisture content in the same situation, directly change the relative humidity (relative humidity to red</p><p>  3.2 Control Problems</p><p>  Such as central air cond

31、itioning system for large, complex process (or object) of the control implementation, usually by some kind of guidelines, the lower its decomposition into a number of subsystems to exercise control, co-ordination in the

32、top performance among the various subsystems, making integration After the system is in some sense the optimal state. Problems in control mainly in: </p><p>  (1) uncertainty Traditional </p><p&g

33、t;  (2) highly nonlinear </p><p>  (3) semi-structured and unstructured </p><p>  (4) system complexity </p><p>  (5)Reliability </p><p>  4. the selection of control

34、strategy </p><p>  The uncertainty of complex systems, since the controlled object (process) is difficult to use the characteristics of the mathematical model accurately described. The traditional PID contro

35、l theory based on classical control and state space representation based on modern control theory methods to achieve high dynamic and static charged object quality control is very difficult, usually with black-box method

36、, that method of input and output description control system analysis and design, a large nu</p><p>  (1) has enough on people's control strategy charged objects and the environment with the knowledge an

37、d using the knowledge of the "wisdom"; </p><p>  (2)is knowledge that can be generalized mathematical model and the non-mathematical description that the mixing process, using open loop control and

38、 the combination of qualitative and quantitative control of the multi-mode control; </p><p>  (3) with variable structure features, can be generally self-optimizing, self-adaptive, self-organization, self-le

39、arning and self-coordination; </p><p>  (4) with compensation and self-healing capabilities, determine decision-making capacity and high reliability. Highlight the advantages of intelligent control strategy

40、is to take full advantage of human control performance, information acquisition, transmission, processing performance results and psychological, physical test data, the establishment of control by a "people" as

41、pects of the model to be controlled object with a machine models complement each other, man-machine system design, providin</p><p>  5 Conclusion </p><p>  Since central air-conditioning system

42、in the energy-saving building automation systems occupy a special position, shown on the central air conditioning system control the pattern of significance. In this paper, the system temperature and humidity control for

43、 a more detailed analysis, and describes the main advantages of intelligent control strategy for the design of similar systems provide useful help.</p><p>  From: Air Conditioning Control and Management</

44、p><p>  中央空調(diào)監(jiān)控系統(tǒng)中溫、濕度控制的相關(guān)問題分析</p><p><b>  1引言</b></p><p>  “綠色建筑”主要強調(diào)的是環(huán)保,節(jié)能,資源和材料的有效利用,特別是對空氣的溫度、濕度、通風(fēng)及潔凈度的要求。因此,空調(diào)系統(tǒng)的應(yīng)用越來越廣泛??照{(diào)控制系統(tǒng)涉及面廣,而要實現(xiàn)的任務(wù)比較復(fù)雜。需要有冷、熱源的支持??照{(diào)機組內(nèi)有大功率的

45、風(fēng)機,但它的能耗很大。在滿足用戶對空氣環(huán)境要求的前提下,只有采用先進的控制策略對空凋系統(tǒng)進行控制,才能達到節(jié)約能源和降低運行費用的目的。 以下將從控制策略角度對與監(jiān)控系統(tǒng)有關(guān)的問題作簡要討論。 </p><p>  2 空調(diào)系統(tǒng)的基本結(jié)構(gòu)及工作原理</p><p>  空調(diào)系統(tǒng)結(jié)構(gòu)組成一般包括下幾部分: </p><p>  (1)新風(fēng)部分 空調(diào)系統(tǒng)在運行過程中必須

46、采集部分室外的新鮮空氣(即新風(fēng)),這部分新風(fēng) 必須滿足室內(nèi)工作人員所需要的最小新鮮空氣量, 因此空調(diào)系統(tǒng)的新風(fēng)取入量決 定于空調(diào)系統(tǒng)的服務(wù)用途和衛(wèi)生要求。 新風(fēng)的導(dǎo)入口一般設(shè)在周圍不受污染影響的地方。這些新風(fēng)的導(dǎo)入口和空調(diào)系統(tǒng)的新風(fēng)管道以及新風(fēng)的濾塵裝置(新風(fēng)空 氣過濾器),新風(fēng)預(yù)熱器(又稱為空調(diào)系統(tǒng)的一次加熱器)共同組成了空調(diào)系統(tǒng)的新 風(fēng)系統(tǒng)。 </p><p>  (2)空氣的凈化部分 空調(diào)系統(tǒng)根據(jù)其用途不同

47、,對空氣的凈化處理方式也不同。因此,在空調(diào)凈化系統(tǒng)中有設(shè)置一級初效空氣過濾器的簡單凈化系統(tǒng), 也有設(shè)置一級初效空氣過 濾器和一級中效空氣過濾器的一般凈化系統(tǒng),另外還有設(shè)置一級初效空氣過濾器,一級中效空氣過濾器和一級高效空氣過濾器的三級過濾裝置的高凈化系統(tǒng)。 </p><p>  (3)空氣的熱,濕處理部分 對空氣進行加熱,加濕和降溫,去濕,將有關(guān)的處理過程組合在一起,稱為空調(diào)系統(tǒng)的熱,濕處理部分。在對空氣進行熱,

48、濕處理過程中,采用表面式空氣 換熱器。設(shè)置在系統(tǒng)的新風(fēng)入口,一次回風(fēng)之前的空氣加熱器稱為 空氣的一次加熱器; 設(shè)置在降溫去濕之前的空氣加熱器, 稱為空氣的二次加熱器; 設(shè)置在空調(diào)房間送風(fēng)口之前的空氣加熱器,稱為空氣的三次加熱器。三次空氣加 熱器主要起調(diào)節(jié)空調(diào)房間內(nèi)溫度的作用,常用的熱媒為熱水或電加熱。在表面式 換熱器內(nèi)通過低溫冷水或制冷劑的稱為水冷式表面冷卻器或直接蒸發(fā)式表面冷 卻器,也有采用噴淋冷水或熱水的噴水室,此外也有采用直接噴水

49、蒸汽的處理方 法來實現(xiàn)空氣的熱,濕處理過程。 </p><p>  (4)空氣的輸送和分配,控制部分 空調(diào)系統(tǒng)中的風(fēng)機和送, 回風(fēng)管道稱為空氣的輸送部分。 風(fēng)管中的調(diào)節(jié)風(fēng)閥, 蝶閥,防火閥,啟動閥及風(fēng)口等稱為空氣的分,控制部分。根據(jù)空調(diào)系統(tǒng)中空氣 阻力的不同,設(shè)置風(fēng)機的數(shù)量也不同,如果空調(diào)系統(tǒng)中設(shè)置一臺風(fēng)機,該風(fēng)機既 起送風(fēng)作用,又起回風(fēng)作用的稱為單風(fēng)機系統(tǒng);如果空調(diào)系統(tǒng)中設(shè)置兩臺風(fēng)機, 一臺為送風(fēng)機,另一臺為回

50、風(fēng)機,則稱為雙風(fēng)機系統(tǒng)。 </p><p>  (5)空調(diào)系統(tǒng)的冷,熱源 空調(diào)系統(tǒng)中所使用的冷源一般分為天然冷源和人工冷源。 天然冷源一般指地 下深井水,人工冷源一般是指利用人工制冷方式來獲得的,它包括蒸汽壓縮式制 冷,吸收式制冷以及蒸汽噴射式制冷等多種形式?,F(xiàn)代化的大型建筑中通常都采 用集中式空調(diào)系統(tǒng)。</p><p>  其工作原理是當環(huán)境溫度過高時,空調(diào)系統(tǒng)通過循環(huán)方式把室內(nèi)的熱量帶

51、 走,以使室內(nèi)溫度維持于一定值。當循環(huán)空氣通過風(fēng)機盤管時,高溫空氣經(jīng)過冷 卻盤管的鋁金屬先進行熱交換,盤管的鋁片吸收了空氣中的熱量,使空氣溫度降 低,然后再將冷凍后的循環(huán)空氣送人室內(nèi)。冷卻盤管的冷凍水由冷卻機提供,冷 卻機由壓縮機,冷凝器和蒸發(fā)器組成。壓縮機把制冷劑壓縮,經(jīng)壓縮的制冷劑進 入冷凝器,被冷卻水冷卻后,變成液體,析 出的熱量 由冷卻水帶走,并在冷卻 塔里排人大氣。液體制冷劑由冷凝器進入蒸發(fā)器進行蒸發(fā)吸熱,使冷凍水降溫, 然后

52、冷凍水進入水冷風(fēng)機盤管吸收空氣 中的熱量,如此周而復(fù)始,循環(huán) 不斷, 把室內(nèi)熱量帶走。當環(huán)境溫度過低時,需要以熱水進入風(fēng)機盤管,和上述原理一 樣,空氣加熱后送人室內(nèi)??諝饨?jīng)過冷卻后,有水分析出,空氣相對濕度減少, 變的干燥,所以需增加濕度,這就要加裝加濕器,進行噴水或噴蒸汽,對空氣進 行加濕處理,用這樣的濕空氣去補充室內(nèi)水汽量的不足。 </p><p>  3 中央空調(diào)系統(tǒng)控制中存在的問題 </p>

53、<p>  3.1 被控對象的特點</p><p>  空調(diào)系統(tǒng)中的控制對象多屬熱工對象,從控制角度分析,具有以下特點:</p><p>  (1)多干擾性 例如,通過窗戶進來的太陽輻射熱是時間的函數(shù),受氣象條件的影響;室外空氣溫度通過圍護結(jié)構(gòu)對室溫產(chǎn)生影響;通過門,窗,建筑縫隙侵入的室外空氣對室溫產(chǎn)生影響;為了換氣(或保持室內(nèi)一定正壓)所采用的新風(fēng),其溫度變化對 室溫有直接影

54、響。此外,電加熱器(空氣加熱器)電源電壓的波動以及熱水加熱器 熱水壓力,溫度,蒸汽壓力的波動等,都將影響室溫。 如此多的干擾,使空調(diào)負荷在較大范圍內(nèi)變化,而它們進入系統(tǒng)的位置,形 式,幅值大小和頻繁程度等,均隨建筑的構(gòu)造( 建筑熱工性能) ,用途的不同而 異,更與空調(diào)技術(shù)本身有關(guān)。在設(shè)計空調(diào)系統(tǒng)時應(yīng)考慮到盡量減少干擾或采取抗 干擾措施。因此,可以說空調(diào)工程是建立在建筑熱工,空調(diào)技術(shù)和自控技術(shù)基礎(chǔ) 上的一種綜合工程技術(shù)。 </p&g

55、t;<p>  (2)多工況性 空調(diào)技術(shù)中對空氣的處理過程具有很強的季節(jié)性。 一年中, 至少要分為冬季, 過渡季和夏季。近年來,由于集散型系統(tǒng)在空調(diào)系統(tǒng)中的應(yīng)用,為多工況的空調(diào) 應(yīng)用創(chuàng)造了良好的條件。由于空調(diào)運行制度 的多樣化,使運行管理和 自動控制 設(shè)備趨于復(fù)雜。因此,要求操作人員必須嚴格按照包括節(jié)能技術(shù)措施在內(nèi)的設(shè)計 要求進行操作和維護,不得隨意改變運行程序和拆改系統(tǒng)中的設(shè)備。 </p><p>

56、;  (3)溫,濕度相關(guān)性 描述空氣狀態(tài)的兩個主要參數(shù)為溫度和濕度, 它們并不是完全獨立的兩個變 量。當相對濕度發(fā)生變化時會引起加濕(或減濕)動作,其結(jié)果將引起室溫波動; 而室溫變化時,使室內(nèi)空氣中水蒸氣的飽和壓力變化,在絕對含濕量不變的情況 下,就直接改變了相對濕度(溫度增高相對濕度減少,溫度降低相對濕度增加)。 這種相對關(guān)聯(lián)著的參數(shù)稱為相關(guān)參數(shù)。顯然,在對溫,濕度都有要求的空調(diào)系統(tǒng) 中,組成自控系統(tǒng)時應(yīng)充分注意這一特性。 </

57、p><p>  3.2 控制中存在的主要問題</p><p>  對于像中央空調(diào)系統(tǒng)這樣的大型復(fù)雜過程(或?qū)ο?的控制實現(xiàn),一般是按某 種準則在低層把其分解為若干子系統(tǒng)實施控制, 在上層協(xié)調(diào)各子系統(tǒng)之間的性能 指標,使得集成后的整個系統(tǒng)處于某種意義下的優(yōu)化狀態(tài)。在控制中存在問題主 要表現(xiàn)在: </p><p><b>  (1)不確定性; </b>

58、</p><p>  (2)高度非線性; </p><p>  (3)半結(jié)構(gòu)化與非結(jié)構(gòu)化; </p><p>  (4)系統(tǒng)復(fù)雜性; </p><p><b>  (5)可靠性。 </b></p><p><b>  4 控制策略的選取</b></p><

59、p>  對于復(fù)雜的不確定性系統(tǒng)而言,由于被控對象(過程)的特性難于用精確的數(shù) 學(xué)模型描述。用傳統(tǒng)的基于經(jīng)典控制理論的 PID 控制和基于狀態(tài)空間描述的近 代控制理論方法來實現(xiàn)對被控對象的高動靜態(tài)品質(zhì)的控制是非常困難的, 一般都 采用黑箱法,即輸入輸出描述法對控制系統(tǒng)進行分析設(shè)計,大量引入人的能量與 智慧,經(jīng)驗與技巧。控制器是用基于數(shù)學(xué)模型和知識系統(tǒng)相結(jié)合的廣義模型進行 設(shè)計的,也就是說對不確定性復(fù)雜系統(tǒng)的控制一般采用智能控制策略。

60、這類控制 系統(tǒng)具有以下基本特點: </p><p>  (1)具有足夠的關(guān)于人的控制策略,被控對象及環(huán)境的有關(guān)知識以及運用這 些知識的“智慧”; </p><p>  (2)是能以知識表示的非數(shù)學(xué)廣義模型和以數(shù)學(xué)描述表示的混合過程,采用 開閉環(huán)控制和定性及定量控制相結(jié)合的多模態(tài)控制方式; </p><p>  (3)具有變結(jié)構(gòu)特點,能總體自尋優(yōu),具有 自適應(yīng),自組織

61、,自學(xué)習(xí)和自協(xié) 調(diào)能力; </p><p>  (4)具有補償和自修復(fù)能力,判斷決策能力和高度的可靠性。智能控制策略 的突出優(yōu)點是充分利用人的控制性能,信息獲取,傳遞,處理性能的研究結(jié)果和 心理,生理測試數(shù)據(jù),建立控制者一“人”環(huán)節(jié)的模型,以便與被控制對象一機 器的模型相互配合,設(shè)計人機系統(tǒng),為系統(tǒng)分析設(shè)計提供靈活性。例如,當建立 被控制對象模型很困難時,可以建立控制者模型,如建立控制專家模型,設(shè)計專 家控制器等

62、;當建立控制者模型很困難時,可以建立被控制對象模型;而設(shè)計被 控對象模型有困難時,又可建“控制者一被控制對象”的聯(lián)合模型,即控制論 系統(tǒng)模型,如“人一人”控制論系統(tǒng)的對策論模型。由于現(xiàn)代傳感變換檢測技術(shù) 和計算機硬件相關(guān)技術(shù)的發(fā)展基本上已經(jīng)妥善地解決了控制系統(tǒng)中的硬件問題, 難點在于信息的處理和信息流的控制, 因此其控制目標的實現(xiàn)和控制功能的完成 往往采用全軟件方式。不同的控制策略所構(gòu)造出的算法其復(fù)雜程度,魯棒性,解 耦性能等差別是很大

63、的,在技術(shù)實現(xiàn)上軟硬件資源成本也不同,人們期待的是成 本最低的控制策略,在這方面仿人智能控制策略具有其獨特的優(yōu)勢。仿人智能控 制是總結(jié),模仿人的控制經(jīng)驗和行為,以產(chǎn)生式規(guī)則描述人在控制方面的啟</p><p><b>  5 結(jié)束語</b></p><p>  由于中央空調(diào)系統(tǒng)在樓宇自動化系統(tǒng)節(jié)能中占據(jù)的特殊地位, 顯示出了對中 央空調(diào)系統(tǒng)控制模式進行研究的重要意義。

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