【正文】 畢業(yè)設(shè)計（論文） 題 目 基于單片機的功率補償設(shè)計 (軟件 ) 英文題目 Based on SCM power pensation design 摘 要 隨著電力系統(tǒng)對電能質(zhì)量要求的日益提高，電壓質(zhì)量對于電力系統(tǒng)的正常運行有著重要意義。電壓能否維持在合格范圍內(nèi)直接影響著電力工業(yè)本身的安全；系統(tǒng)的無功 功率對電壓的影響極大，維持電網(wǎng)正常運行情況下的無功平衡是改善電壓質(zhì)量的基本條件。對電壓無功 進(jìn)行綜合控制可以保證電壓合格，同時還能提高電網(wǎng)的可靠性和經(jīng)濟性。利用變電站中電壓無功控制器 [7]自動調(diào)節(jié)有載變壓分接頭和并聯(lián)補償電容器組可以實現(xiàn)這一綜合控制。供電系統(tǒng)中已經(jīng)有大量的無功補償裝置投入運行，這對電力系統(tǒng)的穩(wěn)定起到了一定的作用。然而，在類似于軋鋼等無功功率動態(tài)變化的工業(yè)場所，由于無功 功率的大小不但隨時間在不斷變化，而且變化的速度很快。 因此我利用單片機 [1]實現(xiàn)對無功補償?shù)闹悄芸刂?，它利用交流采樣，有簡化硬件、降低成本、提高測量的準(zhǔn)確度，能測量動態(tài)交流電量等優(yōu)點。 無功控制器由單片機系統(tǒng)構(gòu)成，它集 數(shù)據(jù)采集、數(shù)據(jù)處理、控制判斷和控制輸出于一身 大大的增加了運算的速度并減少了人力資源。 本裝置通過測量系統(tǒng)電壓和負(fù)荷電流，用單片機進(jìn)行控制，計算出負(fù)荷的無功功率作為控制量，得到晶閘管開關(guān)閉合或斷開的數(shù)據(jù)，并控制相應(yīng)的晶閘管開關(guān)，投入容量適合的電容器組，實現(xiàn)無功動態(tài)補償?？蓱?yīng)用于所有電壓等級的配電網(wǎng)，提高負(fù)荷的功率因數(shù)，降低線路損耗，改善安裝地點的電壓質(zhì)量。同時設(shè)置了 RS485 通訊接口 [6]，可方便的與上位機相連接有利于更方便的控制操作。 關(guān)鍵詞： 無功功率， 相位 檢測 ， 無功補償， 單片機， 投切 電容 組 東華理工 大學(xué)長江學(xué)院畢業(yè)設(shè)計（論文） ABSTRACT ABSTRACT As the electric power system of power quality requirements for increasing the quality of voltage, the normal operation of the power system has important significance. Voltage can be maintained in qualified range directly affect the safety of electric power industry itself, System of reactive power, voltage tremendous influence to maintain the normal operation of power of reactive power balance situation is to improve the quality of the basic conditions of voltage. Voltage reactivepower integrated control can ensure voltage and reactive power balance qualified trend, and can improve the reliability and efficiency of the grid[16]. Use of reactive voltage transformer onload regulating automatic controller variable subsection joints and parallel pensation capacitor can realize the prehensive control. Power supply system has plenty of reactive power pensation devices and the operation of the power system stability plays an important role[20]. However, in a similar to rolling etc reactive power and the dynamic changes of industrial sites, due to the size of the reactive power not only with time changing, and the changes very fast. Therefore I use of microputer intelligent control of reactive power pensation, it is simplified by ac sample, hardware, reduce the cost and improve the accuracy of measurement, the measurement of dynamic power can municate etc. Reactive controller by SCM system[17], it integrates data acquisition, data processing, control and output control in a greatly increased puting speed and reduce the manpower resources. This device through measuring system voltage and current MCU control[18], and calculated load of reactive power, as the control thirstier closing switches or disconnect the data, and the corresponding control thruster switch, investment capacity for the he capacitor, realize the dynamic reactive pensation. Can be applied to all of voltage level, enhancing the load distribution of power factor[19], reduce the line loss, improve the quality of voltage installation location. While setting the restfive 485 munication interface, which can be easily connected with the PC to control operation more convenient. Key words: Reactive power, Power detection, Reactive power pensation, SCM, Cutting capacitance group 東華理工大學(xué)長江學(xué)院畢業(yè)設(shè)計（論文） 目 錄 III 目 錄 0 緒論 .................................................................. 1 功率因數(shù)低、無功功率大的危害 .................................... 1 無功功率補償?shù)母拍? .............................................. 1 無功功率補償?shù)淖饔? .............................................. 2 無功補償?shù)脑?................................................... 2 課題研究的意義 ................................................... 3 1. 方案要求及總體方案 ................................................... 4 方案要求 ......................................................... 4 系統(tǒng)設(shè)計性能和要求 ......................................... 4 投切方式的選擇 ............................................. 4 制方式的選擇 ............................................... 5 總體設(shè)計方案 ..................................................... 6 2. 硬件部分 ............................................................. 8 控制面板 ......................................................... 8 電壓、電流檢測電路 ............................................... 8 運算放大匹配電路 ................................................. 8 十二位 A/D 轉(zhuǎn)換電路 ............................................... 8 相位判別檢測電路 ................................................. 9 單片機 AT89C51 ................................................... 9 LED 顯示電路及鍵盤 ............................................... 9 LED 顯示電路 ................................................ 9 鍵盤 ...................................................... 10 復(fù)位電路 ........................................................ 10 直 流 穩(wěn)壓電源電路 ................................................ 11 無功補償投切電容 ............................................... 12 晶閘管觸發(fā)電路 ................................................. 12 3. 軟件設(shè)計 ............................................................ 14 主程序流程 ...................................................... 14 控制策略 ........................................................ 15 電容器投切流程圖 ................................................ 17 LED 顯示部分流程圖 .............................................. 18 相位檢測中斷子程序流程圖 ........................................ 19 A/D 轉(zhuǎn)換流程圖 .................................................. 20 結(jié) 論 .................................................................. 30 致 謝 .................................................................. 31 參考文獻(xiàn) ................................................................ 32 附錄 一 ................................................................. 33 東華理 工大學(xué)長江學(xué)院畢業(yè)設(shè)計（論文） 緒論 1 0 緒論 隨著國民經(jīng)濟的快速發(fā)展和持續(xù)增長 ,