【正文】 % of the faulty tiles found their way on to the market. This obviously would not do. The lighting level was generally proved totgive 60lumens/ of 1015 lumens/ early production processes and 140 lumens/.For final clour quality of the light was also improved. The result is that only 4% of all faulty tiles reach final inspection and 2% are rejected there. Moreover, clour vision in the final stage is now so good that some tiles rejected for offclour can be accurately regraded according to their shade and sold as seconds . The ability to see clearly that quality go。 R with better lightingAs mentioned previously,the contribution made by good lighting to the quality of a product is not always appreciated. In the manufacture of ornamental tiles,flaws such as deformation, chips cracks etc are inevitable however carefully the process is detecting these faults in tiles at an early stage further expensive and wasteful processing is avoided and the final product quality is improved. The result so f an investigation by one wellknown pany revealed that 20% of the faulty tiles escaped detection during manufacture, even the at the final inspection stage only 2163。 e high degree of process control available and the cleanliness of application are,however,two features which make the use of electricity very suitable and sometimes essential in the manufacture of products of high quality and reliability. Every function within a factory can be said to have some influence on the saleability of the final product. Some of these function s are often regarded as an indirect overhead without rearising the important part they play in achieving a high quality and airconditioning, which can effect the efficiency of work people, are two possible a great deal depends upon the product design and the production methods adopted, and both must be kept unde r constant review.Q amp。 R Year as ambitious and original as would be a great pity if the opportunity were not taken to reexamine the techniques now in use in the light of the technological changes which have taken place in recent years . Even the most conscientious worker can only maintain a high standard of product quality when supported by plant and equipment capable of consistently meeting these standards.influence on product Q amp。 million and is likely to reach 163。s record of reliability for the year ending March 1966 was figures from the National Fault Reporting scheme indicate that the overall average continuity of supply was %.The predominating causes of interruptions were such hazards as gales,lightning,heavy snowfalls and accidental damage caused. For example,by mechanical equipment and workmen39。他在我設(shè)計中給了我許多寶貴的意見和建議。謝謝你們嘔心瀝血的教導(dǎo)。我們這組每個人的畢業(yè)設(shè)計都凝聚著吳老師辛勤的勞動，他的治學(xué)嚴(yán)謹(jǐn)和科學(xué)研究的精神是我永遠學(xué)習(xí)的榜樣。首先，在此我要由衷的感謝我的指導(dǎo)老師陳東陽老師給我悉心的幫助和對我耐心而細致的指導(dǎo)。論文的寫作是枯燥艱辛而又富有挑戰(zhàn)的，在畢業(yè)論文設(shè)計過程中，我遇到過許許多多的困難。在老師的指導(dǎo)和同學(xué)的幫助之下，我基本按時完成了這次畢業(yè)設(shè)計。不過也使我學(xué)到了新的東西，我相信為以后的工作學(xué)習(xí)一定會有很大的幫助。由于本人實際動手經(jīng)驗不足，導(dǎo)致選頻電路模塊實際測驗大電壓示波器顯示效果不是很理想，所測數(shù)據(jù)與理論值相差很大，可能選頻電路焊接導(dǎo)致，亦可能其他原因。信號調(diào)理電路使－~+ V的抬升。模擬信號采集部分前端互感器采用了DVDI001臥式穿芯小型精密電壓互感器(Potential Transformer，PT)和TA14194臥式穿芯小型精密交流電流互感器(Current Transformer ，CT)來來滿足要求，具有精度高、體積小的優(yōu)點。第5章 結(jié)論與總結(jié)本文研究和開發(fā)了一種基于MSP430F149的簡單諧波數(shù)據(jù)采集分析系統(tǒng)。柵欄效應(yīng)不能消除，只能減小。按照數(shù)字信號處理的理論，任何一個有限長序列進行FFT變換，都相當(dāng)于給無限長序列加上一個矩形窗得到。另外在數(shù)據(jù)送到LCD顯示的時候，受限于LCD顯示能力，也會發(fā)生人為的將數(shù)據(jù)截斷和四舍五入，以便于顯示。同時ADC采樣也會帶來量化誤差，使得當(dāng)信號較小時，會產(chǎn)生較大誤差，此外ADC還存在噪聲、積分非線性、采樣時基不匹配、采樣時基抖動等各種問題。(3)同步采樣帶來的誤差同步采樣指的是采樣的各路的電壓和電流信號相位差要求同步，即采樣后它們的相位差與采樣前原始信號的相位差相等。(2)抗混疊濾波帶來的誤差對抗混疊濾波電路進行過分析，由于實際濾波器與理想濾波器之間存在誤差，在截至頻率附近的信號有相應(yīng)的衰減，這將直接導(dǎo)致各次諧波幅值有所衰減。(1)互感器帶來的誤差互感器中由于激磁電動勢的存在，電壓互感器和電流互感器原邊電流和副邊電流在矢量上不再成正比，互感器的實際輸出和理想輸出之間出現(xiàn)了誤差，在硬件調(diào)試過程中，當(dāng)輸入電壓或者電流過大時，會出現(xiàn)波形失真的情況，這種情況就是互感器磁飽和所致。 誤差產(chǎn)生原因分析為了減小測量誤差，提高測量結(jié)果的準(zhǔn)確度，必須明確測量誤差的主要來源，以便估算測量誤差，并采取相應(yīng)措施減小測量誤差。 交流電流有效值最大相對誤差：%。表41 參數(shù)測量數(shù)據(jù)表測量參數(shù)交流電壓/V表頭值1086421實測值交流電流/A表頭值1086421實測值電壓有效值/V實測值電流有效值/A實測值有功功率/W實測值無功功率/var實測值視在功率/V?A實測值功率因素實測值信號頻率/Hz表頭值3035404550556065實測值注：以上數(shù)據(jù)均為測量3次取其平均值。(2)輸入幅度為5V，頻率為20Hz至80Hz的正弦波，測量信號頻率。指令11：讀數(shù)據(jù)。指令9：讀忙信號和光標(biāo)地址 BF：為忙標(biāo)志位，高電平表示忙，此時模塊不能接收命令或者數(shù)據(jù)，如果為低電平表示不忙。(有些模塊是 DL：高電平時為8位總線，低電平時為4位總線)指令7：字符發(fā)生器RAM地址設(shè)置，地址：字符地址*8+字符行數(shù)。R/L，高向左，低向右。指令4：顯示開關(guān)控制D：控制整體顯示的開與關(guān)，高電平表示開顯示，低電平表示關(guān)顯示 C：控制光標(biāo)的開與關(guān)，高電平表示有光標(biāo)，低電平表示無光標(biāo) B：控制光標(biāo)是否閃爍，高電平閃爍，低電平不閃爍。指令3：光標(biāo)和顯示模式設(shè)置 I/D：光標(biāo)移動方向，高電平右移，低電平左移，S:屏幕上所有文字是否左移或者右移。表32 1602指令集指令 RSRWD7D6D5D4D3D2D1D01清屏 00000000012光標(biāo)返回 000000001*3輸入模式 00000001I/DS4顯示控制 0000001DCB5光標(biāo)/字符移位 000001S/CR/L**6功能 00001DLNF**7置字符發(fā)生器地址 0001字符發(fā)生存貯器地址 8置數(shù)據(jù)存貯器地址 001顯示數(shù)據(jù)存貯器地址 9讀忙標(biāo)志和地址 01BF計數(shù)器地址 10 10要寫的數(shù)據(jù) 1111讀出的數(shù)據(jù)指令1：清顯示，光標(biāo)復(fù)位到地址00H位置。 LCD1602引腳定義字符型LCD通常有14條引腳線或16條引腳線的LCD，多出來的2條線是背光電源線VCC(15腳)和地線GND(16腳)，其控制原理與14腳的LCD完全一樣，定義如表31所示。每次輸入指令前都要判斷液晶模塊是否處于忙的狀態(tài)。要顯示字符時要先輸入顯示字符地址，也就是告訴模塊在，哪里顯示字符，圖315是1602 的內(nèi)部顯示地址。與單通道開關(guān)相比，具有輸入信號峰值電壓范圍等于電源電壓以及在輸入信號范圍內(nèi)導(dǎo)通阻抗比較穩(wěn)定等優(yōu)點。CD4066由四個相互獨立的雙向開關(guān)組成，每個開關(guān)有一個控制信號，開關(guān)中的p和n器件在控制信號作用下同時開關(guān)。引出端排列與CC4016一致，但具有比較低的導(dǎo)通阻抗。由于本設(shè)計是簡易電能質(zhì)量檢測儀所以通過使用四雙向模擬開關(guān)CD4066結(jié)合RC有源帶通濾波電路電路篩選出9次諧波。為測定系統(tǒng)所用選頻電路性能，做了以下測試：,接三次諧波(150Hz)選頻電路輸入端，調(diào)整正弦信號頻率用示波器，將電壓峰峰值折算為最大值不超過1的數(shù)據(jù)值即表中的轉(zhuǎn)換值，可觀察到該選頻電路傳輸系數(shù)為1，中心頻率為150Hz，通頻帶約為9Hz。 倍范圍內(nèi)上下兩個頻率為；增益為通帶中心頻率處的信號放大倍數(shù)。電路圖如圖313所示。圖312 模擬量采集系統(tǒng)電路 諧波檢測電路諧波數(shù)據(jù)采集系統(tǒng)的硬件結(jié)構(gòu)設(shè)計是系統(tǒng)整體功能實現(xiàn)的基礎(chǔ)，它直接關(guān)系到系統(tǒng)運行的穩(wěn)定性和采集到的數(shù)據(jù)的可靠性等問題。根據(jù)集成運放的“虛短”和“虛斷”原理及電壓電流運算原則可分析得：若使輸出電壓不超出0~ V，可調(diào)節(jié)RY20和RY32，使－~+ V的抬升。~+ V的抬升。設(shè)計選取了DVDI001臥式穿芯小型精密電壓互感器(Potential Transformer，PT)和TA14194臥式穿芯小型精密交流電流互感器(Current Transformer，CT)來來滿足以上要求。采集到的交流電壓和交流電流經(jīng)過隔離電路和信號調(diào)理電路后進入MSP430F149的A/D通道進行轉(zhuǎn)換。簡單過零比較器電路圖、傳輸特性、輸出特性如圖311所示。上圖中集成運放TL062工作在非線性狀態(tài)，因此當(dāng)時，；當(dāng)時。比較器的輸入信號是連續(xù)變化的模擬量，而輸出信號是數(shù)字量1和0，因此可以為采樣電路提供硬件中斷。如圖310為硬件過零中斷電路。 過零檢測電路設(shè)計考