2023年全國(guó)碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁(yè)
已閱讀1頁(yè),還剩6頁(yè)未讀, 繼續(xù)免費(fèi)閱讀

下載本文檔

版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請(qǐng)進(jìn)行舉報(bào)或認(rèn)領(lǐng)

文檔簡(jiǎn)介

1、<p><b>  附錄3</b></p><p>  The Controller of the Domestic Electric Water-Heater</p><p>  1. The perspectives of appliance</p><p>  Water-heater is a kind of domestic

2、 electric appliance which can be used in bathroom, wash room and kitchen. The types of water-heater available in the market at present includes: electric water-heater, solar water-heater, gas water-heater. To be specific

3、ally in China, the use of solar water-heater is limited by the weather and the scope for use is narrow while gas water-hater is fueled by petrol and gas, the supply of which will be difficult to meet the increasing deman

4、ds and bad for environment</p><p>  2. The Goal for Design</p><p>  There are two kinds of electric water-heaters available in the market at present: the continual fluent type and water storage

5、type. Considering the special demand of the moist working conditions on single chip, we adopt the newly promoted MC68HC08 single chip by Motorola to be the control center. With its high resistance to interference, steady

6、 working, flash memory and so on, this single chip can satisfy the demand of the electric water-heater with high performance. Also considering the fierce </p><p>  3. The LZC-CI Hardware Design</p>&l

7、t;p>  3.1 Technology Standards and Characteristics</p><p>  The main function of the controller is to control the temperature. Besides that, it has to realize the following functions:</p><p>

8、  To display the real-time temperature of water, the range is 0~99℃. </p><p>  To set the temperature of water arbitrarily within 20~80℃.</p><p>  Have the function of appointment which enables

9、24 hour turning on setting willfully.</p><p>  Have LTD to display real-time temperature digitally. When setting, the temperature and the time set will be displayed by flicker and the controller will have in

10、structions of appointment, heat preservation and heating. </p><p>  Able to look over and revise the time of system. </p><p>  Equipped with remote controller, the control will be easy and simpl

11、e.</p><p>  Cut the power swiftly when temperature is too high and alarm.</p><p>  When electricity leaks, cut the power swiftly and propose alarming. </p><p>  When the power is cu

12、t, the data set can be preserved. </p><p>  3.2 The Structure of the System</p><p>  The system consists of two main parts: the main controller of water-heater and the remote controller, realize

13、d by two pieces of 68hc908gr8 respectively. </p><p>  3.2.1 The Power Supply and the Clock Circuit</p><p>  The power circuit consists of the transformation bridge, the rectification bridge, the

14、 filter resistance, the pressure sensitive resistance and integration voltage-stabilizer circuit MC7812T and MC7805T, which can provide +5V and the +12V power source for the controller. OutsideOSC1 and OSC2, 8 kHz crysta

15、l oscillator is connected with the circuit.</p><p>  3.2.2 The Keyboard</p><p>  The function of controlling and the enactment of parameters are realized by the pressing the keys. The two keys o

16、f the system’s main controller complete directly the functions of heating and the inquiring of the water level, using the keyboard severance pattern and PTA2, PTA3 as the input entrance of the pressing. The keyboard of t

17、he remote controller is designed into matrix type. The pressing of the keys will initiate the keyboard severance, by scanning from line to line; the number of the key </p><p>  3.2.3 The Display Circuit</

18、p><p>  Considering that the working environment is humid, the main controller takes LED Nixie tube to display. It takes the main way of SPI to expand two piece of 74LS164 as the output orifice of the static de

19、monstration of the seven-segment display. When there is no pressing, the main controller will display the current temperature of water and the remote controller will display the current time; when setting or inquiring, t

20、he remote controller and main controller will flash to display the information</p><p>  3.2.4 The Real-time Temperature of Water and the Circuit of Water-Level Detecting</p><p>  The thermistor

21、will transmit the temperature information into the voltage information and then will be input into CPU by the PTB0 A/D transformation module. After checking, the real-time temperature will be deduced. The circuit of wate

22、r-level detecting consists of the parallel connection of three resistances with different resistance value. The electricity of the electrode is small (only several microamperes), thus the erosion is little which suits th

23、e wide range variety of the resistance of wat</p><p>  3.2.5 The Detecting of Electricity Leaking and Alarming Circuit</p><p>  Since the working environment of water-heater is humid, the contro

24、ller should be able to detect the electricity leaking to ensure the safety of the user. Under normal circumstance, the electric current passing the magnetic circle is the same but with opposite directions. The magnetic d

25、etecting circle wouldn’t sense any signal of electric current and the integrated circuit of electricity leaking detecting will output low electric level. When the electric current leaks, the electric current passin</p

26、><p>  Generally speaking, CPU will send out a reliable pulse for leaking protection every 10ms to replace the ordinary detecting switch and control the connection of crystal tube. So the electric current passi

27、ng the magnetic circle is larger than 10 MA, which will be detected by the detecting magnetic circle as stimulant signal for leaking, magnified by M54123L and inverted by audion and then output to CPU.CPU will judge whet

28、her the detection is eligible. If there is signal, the detection is eligible </p><p>  3.2.6 The Protection Circuit When Heating and Relay Are Out of Control</p><p>  Under normal working condit

29、ions, the two repays can carry on double-pole separation of power to ensure that when heating stops, the heating system is completely isolated from the electricity outside. It is almost impossible for two relay to have a

30、 screw loose simultaneously, however, during the normal life of electric water-heater, it is possible that one relay will have a screw loose. If it is not dealt with in time, the other relay will possibly have the same p

31、roblem later which may result rea</p><p>  3.2.7 The Remote Controller</p><p>  The remote controller utilizes simple controlling circuit which doesn’t decrease the functions. Some hardware circ

32、uits will be realized by software and the interference resisting has been considered. Since the supply for buttery has to save energy, the remote controller uses the low-consumption model. When the system is not working,

33、 it stops. When it begins working, one has to use the keyboard signal to end the low-consumption model and turn into normal (press the key to evoke the system). The l</p><p>  4. The Software Design</p>

34、;<p>  The whole programs consist of the main program, service intermitting program and numerous subprogram of functional model. Among them, the main program includes the transmitting subprogram (the level and tem

35、perature of water), subprogram of keyboard dealing and displaying, subprogram of heating controlling (the function of output comparison is used), subprogram of infrared signal receiving, the subprogram of leaking and bur

36、ning protection, subprogram of calendric clock of the TBM module, subprogr</p><p>  4.1 The Main Program </p><p>  The main program has to initialize the working parameters of the system, mainly

37、 that of CPU timer, COP module, A/D transforming, the intermitting of keys, etc. Later, the main program alternatively uses the subprograms of each functional module. The dealing the relative incidents relies on the flag

38、 bit and the judgment of flag bit.</p><p>  4.2 The subprogram of keyboard dealing and displaying</p><p>  This program is mainly designed to judge the electric level of the orifice I/O. when th

39、e keys are pressed, the keyboard is in a static state, while when stopping pressing, relative dealings will be carried on. When setting and inquiring, the keys will flicker to display the result of setting and inquiring,

40、 or the real-time temperature of water is displayed.</p><p>  4.3 The Subprogram of Heating Controlling</p><p>  This program is used to judge whether there is appointment and heating and to dea

41、l with it according to the procedures. To avoid the frequent starting of the heating wire, the heating controlling adopts the hysteretic error controlling. When heating stops, the heating wire will start work only when t

42、he real-time temperature of water is lower than the target temperature for some distance. There are two kinds of heating to satisfy different powers: rapid heating and ordinary heating. In normal and</p><p>

43、  4.4 The Subprogram of Remote Signal Dealing </p><p>  Sending: press the key with remote controller, set the flag bit, get the number of the key through dynamic scanning and send the coding by output compa

44、rison according to the flag bit and the number of the key; Receiving: get the signal by input catching, set the flag bit and read the number of the key and submit to main program to deal with.</p><p>  4.5 T

45、he Subprogram for Delaying</p><p>  The whole system would use the subprogram for timing and delaying in many situations, like when the keyboard judges to eliminate vibration, the display of flicker and fadi

46、ng display, input catching and calendric clock, etc.</p><p>  4.6 The protection Subprogram</p><p>  In normal situation, the leaking detection will output low electric level. Once the electrici

47、ty leaks, the electricity output is high and will be cut off. The whole circuit of power will be cut off as soon as possible by the protection circuit to ensure the safety of the user. When the temperature is too high or

48、 too low, the heating will be turned off automatically and the buzzer will buzz to warn.</p><p>  5. The Extension of the Design</p><p>  With the development of information technology, intellig

49、ent domestic appliances will gradually step into families. Based on this design, making use of the resources of 68HC908GR8 and SCI and USB module to connect domestic appliances with computer and internet by telephone wir

50、e, they can be controlled from long-distance, thus making life easy and convenient. </p><p><b>  . </b></p><p>  智能家用電熱水器控制器</p><p><b>  1. 應(yīng)用前景</b></p>

51、;<p>  熱水器是一種可供浴室,洗手間及廚房使用的家用電器。目前市場(chǎng)上熱水器主要品種有:電熱水器、太陽能熱水器、燃?xì)鉄崴鳌>椭袊?guó)的具體情況而言,由于太陽能熱水器的使用受天氣原因的限制,使用范圍狹窄,燃?xì)鉄崴饔捎谝允?、天然氣為燃料,而燃料供?yīng)量又難以滿足人們?nèi)找嬖鲩L(zhǎng)的需求,且不利于環(huán)境,因此電熱水器越來越受到消費(fèi)者的青睞。根據(jù)中國(guó)商業(yè)聯(lián)合會(huì)前不久的統(tǒng)計(jì),電熱水器的市場(chǎng)份額在銷售數(shù)量和銷售收入兩個(gè)方面都已經(jīng)超過了長(zhǎng)期

52、以來占優(yōu)勢(shì)的燃?xì)鉄崴鳌T撝行念A(yù)計(jì),在城市電網(wǎng)更大范圍改造和城市住房市場(chǎng)大規(guī)模啟動(dòng)的帶動(dòng)下,今后幾年我國(guó)電熱水器市場(chǎng)將呈現(xiàn)強(qiáng)勁增長(zhǎng)勢(shì)頭。</p><p><b>  2. 設(shè)計(jì)目標(biāo)</b></p><p>  目前市場(chǎng)上的電熱水器有兩種,連續(xù)水流式和貯水式。由于考慮到熱水器的潮濕的工作環(huán)境對(duì)單片機(jī)的特殊要求,我們采用了摩托羅拉新推出MC68HC08系列的單片機(jī)作為控制

53、中心。它具有抗干擾能力強(qiáng),工作可靠穩(wěn)定,自帶flash閃存等特點(diǎn),完全滿足高性能的電熱水器的控制要求。同時(shí)考慮到家電業(yè)的激烈競(jìng)爭(zhēng),節(jié)約生產(chǎn)成本,我們用盡量簡(jiǎn)單的器件實(shí)現(xiàn)這些功能,并充分利用內(nèi)外圍功能,以提高產(chǎn)品的性價(jià)比,稍加改進(jìn),便能以較低成本應(yīng)用于實(shí)際批量生產(chǎn)中。</p><p>  3. LZC-CI硬件設(shè)計(jì)</p><p>  3.1 技術(shù)指標(biāo)及特點(diǎn):</p><

54、p>  控制器的最主要目的是對(duì)水溫進(jìn)行控制,除此之外還實(shí)現(xiàn)下述功能:</p><p>  實(shí)時(shí)顯示水溫,范圍為0~99℃</p><p>  可在20~80℃范圍任意設(shè)定水溫</p><p>  具有預(yù)約功能,24h任意設(shè)定開機(jī)時(shí)間</p><p>  具有LED數(shù)碼顯示實(shí)時(shí)溫度,進(jìn)行設(shè)定操作時(shí)閃爍顯示設(shè)定水溫、時(shí)間,并有預(yù)約、保溫/加

55、熱指示</p><p>  可隨時(shí)察看和校正系統(tǒng)時(shí)鐘</p><p>  配有遙控器,控制更加簡(jiǎn)單方便</p><p>  超溫?cái)嚯姳Wo(hù)并報(bào)警功能</p><p>  出現(xiàn)流故障時(shí),迅速切斷電源并提示報(bào)警功能</p><p>  系統(tǒng)斷電能保護(hù)設(shè)定數(shù)據(jù)</p><p><b>  3.

56、2 系統(tǒng)結(jié)構(gòu)</b></p><p>  系統(tǒng)分兩個(gè)主要部分:熱水器主控制器與遙控器,采用兩片68hc908gr8分別實(shí)現(xiàn)。</p><p>  3.2.1 電源與時(shí)鐘電路。</p><p>  電源電路由變壓橋、整流橋、濾波電阻、壓敏電阻和集成穩(wěn)壓電路MC7812T及MC7805T組成,可為控制器提供+5V和+12V電源。OSC1,OSC2外接8kHz

57、晶體振蕩器。</p><p><b>  3.2.2 鍵盤。</b></p><p>  控制器的功能及參數(shù)設(shè)定都是通過按鍵來實(shí)現(xiàn),本系統(tǒng)主控制器兩個(gè)按鍵完成直接加熱及查詢水位的功能,采用鍵盤中斷模式,PTA2,PTA3作為按鍵的輸入口。遙控器鍵盤采用矩陣式,當(dāng)有按鍵按下是引發(fā)鍵盤中斷,通過逐行掃描判斷所按鍵號(hào),送寄存器保存并發(fā)送,主程序接收到鍵號(hào)后在鍵盤處理程序中進(jìn)

58、行處理。機(jī)械式開關(guān)在斷開和閉合瞬間有抖動(dòng)過程,程序設(shè)計(jì)中采用軟件延時(shí)消抖。</p><p>  3.2.3 顯示電路</p><p>  考慮到使用環(huán)境空氣濕度較大,故主控制器顯示采用LED數(shù)碼管進(jìn)行顯示。采用SPI主方式擴(kuò)展兩片74LS164,作為七段顯示器靜態(tài)顯示的段數(shù)據(jù)輸出口。在無按鍵狀態(tài)下,主控制器顯示當(dāng)前水溫,遙控器顯示當(dāng)前時(shí)間;當(dāng)進(jìn)行設(shè)定或查詢時(shí),遙控器lcd及主控制器led均

59、閃爍顯示設(shè)定或查詢信息,按鍵放開一定時(shí)間后自動(dòng)返回一般狀態(tài)。</p><p>  3.2.4 實(shí)時(shí)水溫及水位檢測(cè)電路。 </p><p>  熱敏電阻將溫度信息轉(zhuǎn)換為電壓信息,經(jīng)A/D轉(zhuǎn)換模塊中PTB0輸入CPU,查表后得到實(shí)時(shí)水溫。水位檢測(cè)為三個(gè)并聯(lián)的不同阻值的電阻,電路的電極電流較小(幾個(gè)微安),電腐蝕小,適用水電阻變化范圍大(10 K一100K歐)。某電阻所在水位未到達(dá),電阻截止;

60、水位到達(dá),電阻導(dǎo)通,組成并聯(lián)電路。將不同阻值所分得的電壓經(jīng)PTB1轉(zhuǎn)換后,可判斷出水位信息(高、中、低、干燒)。</p><p>  3.2.5漏電檢測(cè)及報(bào)警電路</p><p>  熱水器工作環(huán)境潮濕,為了保證使用者安全,控制器應(yīng)具備漏電檢測(cè)功能。在正常情況下,流過磁環(huán)的電流大小相等,方向相反,磁環(huán)檢測(cè)線圈無感應(yīng)電流信號(hào),漏電檢測(cè)集成電路輸出低電平。當(dāng)出現(xiàn)漏電電流時(shí),由于流過磁環(huán)的電流不

61、平衡,于是磁環(huán)檢測(cè)線圈感應(yīng)出漏電信號(hào),經(jīng)集成電路M54123L 放大輸出高電平,經(jīng)三極管倒相后輸出至CPU。CPU接收到漏電信號(hào),則停止加熱保溫及鍵盤操作,結(jié)束工程程序并發(fā)出報(bào)警信號(hào),電源指示燈閃爍警示,蜂鳴器連續(xù)嗚響。</p><p>  正常情況下,CPU 每隔10ms就發(fā)出一個(gè)漏電保護(hù)可靠性自檢脈沖,代替普通漏電開關(guān)的試驗(yàn)按鈕,控制晶體管導(dǎo)通,于是磁環(huán)流過一個(gè)大于10mA 的電流,該電流作為模擬漏電信號(hào)被磁

62、環(huán)檢測(cè),經(jīng)M54123L放大及三極管倒相后,輸出至CPU。CPU自動(dòng)判斷是否為自檢信號(hào)以及自檢是否合格,有信號(hào)則自檢合格,繼續(xù)執(zhí)行程序;無信號(hào)則自檢不合格,自動(dòng)停止加熱保溫及鍵盤操作,結(jié)束工作程序并發(fā)出報(bào)警信號(hào),電源指示燈閃爍警示,蜂鳴器連續(xù)嗚響,從而確保電熱水器的安全使用。在漏電保護(hù)及自檢不合格情況下,只有關(guān)閉電源及排除故障后,重新接通電源才能工作。</p><p>  3.2.6 加熱及繼電器失控保護(hù)電路:&

63、lt;/p><p>  電熱水器正常工作狀態(tài)下,二繼電器觸點(diǎn)對(duì)加熱管的電源能執(zhí)行雙極斷開,可有效地保證當(dāng)停止加熱時(shí),加熱系統(tǒng)可完全與外電隔離.兩只繼電器同時(shí)出現(xiàn)故障的幾率是極低的,但在熱水器正常壽命期間,單只繼電器出現(xiàn)此故障卻是極有可能的,而且,此時(shí)如不及時(shí)處理解決,另一繼電器很有可能不久后也跟著產(chǎn)生此類故障而導(dǎo)致真正的危險(xiǎn)。因此,解決問題的關(guān)鍵是必須在有一繼電器出現(xiàn)此故障后,系統(tǒng)可以及時(shí)檢測(cè)到,并依靠另一暫時(shí)尚可以

64、正常工作的繼電器執(zhí)行系統(tǒng)的安全保護(hù)措施,可以有效地檢測(cè)到兩個(gè)繼電器中任一個(gè)或同時(shí)兩個(gè)觸點(diǎn)出現(xiàn)粘死、斷開故障時(shí)的情況。</p><p><b>  3.2.7 遙控器</b></p><p>  遙控部分采用簡(jiǎn)單控制電路,又不會(huì)減少功能,將有些硬件電路用軟件實(shí)現(xiàn),并且充分考慮到了抗干擾問題。整個(gè)遙控器由于電池供電需要節(jié)省能量,采用低功耗模式,系統(tǒng)不工作時(shí)處于stop狀態(tài)

65、,用鍵盤信號(hào)中斷低功耗模式進(jìn)入正常模式(按鍵喚醒系統(tǒng)),低壓復(fù)位采用MC34064復(fù)位。鍵盤接入采用雙列矩陣式,接入PTA0~PTA3口,設(shè)置為keyboard狀態(tài),這樣鍵盤一按下馬上產(chǎn)生鍵盤中斷,使系統(tǒng)由stop狀態(tài)退出進(jìn)入正常狀態(tài)。晶振為6MHZ。紅外信號(hào)輸出采用軟件編碼方式,主控制器軟件解碼。為節(jié)省成本,顯示采用LCD 定制顯示方式,驅(qū)動(dòng)使用4543驅(qū)動(dòng)+譯碼。</p><p><b>  4.

66、軟件設(shè)計(jì)</b></p><p>  統(tǒng)軟件由主程序,中斷服務(wù)程序及若干功能模塊子程序組成。其中主控制器子程序包括A/D轉(zhuǎn)換子程序(水位、水溫),鍵盤處理及顯示子程序,加熱控制子程序(使用輸出比較功能),紅外信號(hào)接收子程序(使用輸入捕捉功能),漏電、干燒保護(hù)子程序,TBM模塊日歷鐘子程序,數(shù)據(jù)保存子程序,延時(shí)子程序等組成。中斷主要有定時(shí)中斷,鍵盤輸入中斷,TIM輸入捕捉中斷,TBM模塊中斷等。遙控器子

67、程序主要有按鍵處理子程序,紅外信號(hào)發(fā)射子程序,LCD顯示子程序,TBM模塊日歷鐘子程序。</p><p>  4.1 主程序。主程序要先初始化系統(tǒng)的工作參數(shù),主要是CPU的定時(shí)器,COP模塊、A/D轉(zhuǎn)換、端口、鍵中斷等的工作模式參數(shù)設(shè)定。之后系統(tǒng)主程序循環(huán)調(diào)用各個(gè)功能模塊子程序。對(duì)相關(guān)事件的處理依靠標(biāo)志位和判斷標(biāo)志位實(shí)現(xiàn)。</p><p>  4.2 鍵盤處理及顯示子程序。此程序主要是判斷

68、I/O口的高低電平進(jìn)行的。有按鍵按下進(jìn)入鍵中斷置標(biāo)志位,等松開后再進(jìn)行相應(yīng)的處理。在進(jìn)行設(shè)置及查詢操作時(shí)會(huì)閃爍顯示設(shè)置及查詢結(jié)果,否則顯示實(shí)時(shí)水溫。</p><p>  4.3 加熱控制子程序。判斷標(biāo)志位有否預(yù)約、加熱標(biāo)志。之后依流程進(jìn)行處理。為防止加熱絲頻繁啟動(dòng),加熱控制采用回差控制,停止加熱后只有實(shí)時(shí)水溫低于目標(biāo)溫度一定溫度后,才會(huì)再次啟動(dòng)加熱絲工作。為滿足不同功率要求,加熱方式有快速加熱和普通兩種,在一般情

69、況下及預(yù)約狀態(tài)下均采用普通方式,以控制用電功率。</p><p>  4.4 遙控信號(hào)處理子程序。發(fā)送:當(dāng)遙控器按鍵按下,設(shè)置標(biāo)志位,并通過動(dòng)態(tài)掃描方式讀取鍵號(hào),之后按標(biāo)志位及鍵號(hào)利用輸出比較進(jìn)行編碼發(fā)送。接收:利用輸入捕捉功能獲得信號(hào),接受成功后設(shè)標(biāo)志位并讀取鍵號(hào)供主程序進(jìn)行處理。</p><p>  4.5 延時(shí)子程序。所有工作多處用到定時(shí)及延時(shí)子程序:鍵盤判斷消抖延時(shí),閃爍顯示時(shí)的顯

70、示及消隱延時(shí),輸入捕捉,日歷鐘等。</p><p>  4.6 安全保護(hù)子程序。在正常情況下,漏電檢測(cè)電路輸出低電平。一旦出現(xiàn)漏電現(xiàn)象,漏電檢測(cè)電路輸出高電平,引起中斷,并以最快速度使漏電保護(hù)電路切斷整個(gè)電源電路,保證使用者安全。當(dāng)溫度過高或水位過低時(shí),自動(dòng)關(guān)加熱并開啟蜂鳴器向主人報(bào)警有異常情況發(fā)生。</p><p><b>  5. 設(shè)計(jì)擴(kuò)展</b></p&g

溫馨提示

  • 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請(qǐng)下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請(qǐng)聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁(yè)內(nèi)容里面會(huì)有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
  • 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫(kù)僅提供信息存儲(chǔ)空間,僅對(duì)用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理,對(duì)用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對(duì)任何下載內(nèi)容負(fù)責(zé)。
  • 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容,請(qǐng)與我們聯(lián)系,我們立即糾正。
  • 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時(shí)也不承擔(dān)用戶因使用這些下載資源對(duì)自己和他人造成任何形式的傷害或損失。

評(píng)論

0/150

提交評(píng)論