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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。目前市場上熱水器主要品種有:電熱水器、太陽能熱水器、燃氣熱水器。就中國的具體情況而言,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,燃氣熱水器由于以石油、天然氣為燃料,而燃料供應(yīng)量又難以滿足人們?nèi)找嬖鲩L的需求,且不利于環(huán)境,因此電熱水器越來越受到消費者的青睞。根據(jù)中國商業(yè)聯(lián)合會前不久的統(tǒng)計,電熱水器的市場份額在銷售數(shù)量和銷售收入兩個方面都已經(jīng)超過了長期

52、以來占優(yōu)勢的燃氣熱水器。該中心預(yù)計,在城市電網(wǎng)更大范圍改造和城市住房市場大規(guī)模啟動的帶動下,今后幾年我國電熱水器市場將呈現(xiàn)強勁增長勢頭。</p><p><b>  2. 設(shè)計目標(biāo)</b></p><p>  目前市場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)境對單片機的特殊要求,我們采用了摩托羅拉新推出MC68HC08系列的單片機作為控制

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

54、p>  控制器的最主要目的是對水溫進行控制,除此之外還實現(xiàn)下述功能:</p><p>  實時顯示水溫,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)定開機時間</p><p>  具有LED數(shù)碼顯示實時溫度,進行設(shè)定操作時閃爍顯示設(shè)定水溫、時間,并有預(yù)約、保溫/加

55、熱指示</p><p>  可隨時察看和校正系統(tǒng)時鐘</p><p>  配有遙控器,控制更加簡單方便</p><p>  超溫斷電保護并報警功能</p><p>  出現(xiàn)流故障時,迅速切斷電源并提示報警功能</p><p>  系統(tǒng)斷電能保護設(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)分兩個主要部分:熱水器主控制器與遙控器,采用兩片68hc908gr8分別實現(xiàn)。</p><p>  3.2.1 電源與時鐘電路。</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現(xiàn),本系統(tǒng)主控制器兩個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,送寄存器保存并發(fā)送,主程序接收到鍵號后在鍵盤處理程序中進

58、行處理。機械式開關(guān)在斷開和閉合瞬間有抖動過程,程序設(shè)計中采用軟件延時消抖。</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)碼管進行顯示。采用SPI主方式擴展兩片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)前時間;當(dāng)進行設(shè)定或查詢時,遙控器lcd及主控制器led均

59、閃爍顯示設(shè)定或查詢信息,按鍵放開一定時間后自動返回一般狀態(tài)。</p><p>  3.2.4 實時水溫及水位檢測電路。 </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,查表后得到實時水溫。水位檢測為三個并聯(lián)的不同阻值的電阻,電路的電極電流較小(幾個微安),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,電阻截止;

60、水位到達,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漏電檢測及報警電路</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)檢測線圈無感應(yīng)電流信號,漏電檢測集成電路輸出低電平。當(dāng)出現(xiàn)漏電電流時,由于流過磁環(huán)的電流不

61、平衡,于是磁環(huán)檢測線圈感應(yīng)出漏電信號,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,則停止加熱保溫及鍵盤操作,結(jié)束工程程序并發(fā)出報警信號,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)出一個漏電保護可靠性自檢脈沖,代替普通漏電開關(guān)的試驗按鈕,控制晶體管導(dǎo)通,于是磁環(huán)流過一個大于10mA 的電流,該電流作為模擬漏電信號被磁

62、環(huán)檢測,經(jīng)M54123L放大及三極管倒相后,輸出至CPU。CPU自動判斷是否為自檢信號以及自檢是否合格,有信號則自檢合格,繼續(xù)執(zhí)行程序;無信號則自檢不合格,自動停止加熱保溫及鍵盤操作,結(jié)束工作程序并發(fā)出報警信號,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電路:&

63、lt;/p><p>  電熱水器正常工作狀態(tài)下,二繼電器觸點對加熱管的電源能執(zhí)行雙極斷開,可有效地保證當(dāng)停止加熱時,加熱系統(tǒng)可完全與外電隔離.兩只繼電器同時出現(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,此時如不及時處理解決,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。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)可以及時檢測到,并依靠另一暫時尚可以

64、正常工作的繼電器執(zhí)行系統(tǒng)的安全保護措施,可以有效地檢測到兩個繼電器中任一個或同時兩個觸點出現(xiàn)粘死、斷開故障時的情況。</p><p><b>  3.2.7 遙控器</b></p><p>  遙控部分采用簡單控制電路,又不會減少功能,將有些硬件電路用軟件實現(xiàn),并且充分考慮到了抗干擾問題。整個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)不工作時處于stop狀態(tài)

65、,用鍵盤信號中斷低功耗模式進入正常模式(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)退出進入正常狀態(tài)。晶振為6MHZ。紅外信號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)動使用4543驅(qū)動+譯碼。</p><p><b>  4.

66、軟件設(shè)計</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),紅外信號接收子程序(使用輸入捕捉功能),漏電、干燒保護子程序,TBM模塊日歷鐘子程序,數(shù)據(jù)保存子程序,延時子程序等組成。中斷主要有定時中斷,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)用各個功能模塊子程序。對相關(guān)事件的處理依靠標(biāo)志位和判斷標(biāo)志位實現(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口的高低電平進行的。有按鍵按下進入鍵中斷置標(biāo)志位,等松開后再進行相應(yīng)的處理。在進行設(shè)置及查詢操作時會閃爍顯示設(shè)置及查詢結(jié)果,否則顯示實時水溫。</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。之后依流程進行處理。為防止加熱絲頻繁啟動,加熱控制采用回差控制,停止加熱后只有實時水溫低于目標(biāo)溫度一定溫度后,才會再次啟動加熱絲工作。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,并通過動態(tài)掃描方式讀取鍵號,之后按標(biāo)志位及鍵號利用輸出比較進行編碼發(fā)送。接收:利用輸入捕捉功能獲得信號,接受成功后設(shè)標(biāo)志位并讀取鍵號供主程序進行處理。</p><p>  4.5 延時子程序。所有工作多處用到定時及延時子程序:鍵盤判斷消抖延時,閃爍顯示時的顯

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

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