【正文】 pressure control device. Through control thyristor trigger angle, the AC output fundamental voltage effective value of control to achieve pressure and speed adjustment. The overall structure of the system mainly by the main circuit, driving circuit, a photoelectric isolation circuit, trigger, voltage and current detection and protection circuit, stc89c51rc SCM, tachometer generator. Pressure regulating speed circuit is simple, low cost, simple operation, convenient and high requirement of speed performance, small capacity dragging device used in. KeyWords:Thyristor,Voltage Control,SCM 湖南科技大學本科生畢業(yè)設計（論文） iii 目 錄 摘 要 .......................................................................................................................... i ABSTRACT................................................................................................................... ii 第一章 緒論 ................................................................................................................ 1 交流調速的發(fā)展狀況 ....................................................................................... 1 現(xiàn)代交流調速技術的應用 ............................................................................... 1 現(xiàn)代交流調速技術的發(fā)展 ............................................................................... 2 第二章 三相異步電動機交流調速 ...................................................................... 4 交流調速方案 ................................................................................................... 4 變級調速 .................................................................................................. 4 變頻調速 .................................................................................................. 4 變轉差率調速 .......................................................................................... 4 第三章 交流調壓主電路設計 ............................................................................... 8 主電路及其工作原理 ....................................................................................... 8 主電路裝置 .............................................................................................. 8 主電路原理 .............................................................................................. 8 交流調壓調速控制主回路設計 ..................................................................... 10 主電路參數(shù)及元器件選型 ............................................................................. 11 主電路參數(shù)要求 .................................................................................... 11 晶閘管 選擇 ............................................................................................ 11 濾波電容的選擇 .................................................................................... 11 阻容吸收電路參數(shù)計算 ........................................................................ 11 壓敏電阻的選擇 .................................................................................... 12 第四章 控制電路設計 ........................................................................................... 13 單片機控制線路 ............................................................................................. 13 單片機 STC89C51RC 的組成及引腳 ................................................... 14 A/D 芯片 ADC0809 及其工作原理 ....................................................... 16 單片機的幾個外圍電路 ................................................................................. 17 時鐘電路 ................................................................................................ 17 復位電路 ................................................................................................ 18 速度 檢測 電路 ........................................................................................ 19 湖南科技大學本科生畢業(yè)設計（論文） iv 過壓檢測 保護電路 ................................................................................ 19 同步輸入電路及移相觸發(fā)脈沖的產生 ......................................................... 20 同步信號輸入電路 ................................................................................ 20 觸發(fā)脈沖線路與驅動電路 .................................................................... 20 晶閘管觸發(fā)驅動 ............................................................................................. 23 PID 調節(jié)模塊控制原理和有關的設計 .......................................................... 23 系統(tǒng)工作原理 ................................................................................................. 25 第五章 系統(tǒng)軟件的總體設計及流程圖 .......................................................... 26 主程序 ............................................................................................................. 26 主程序流程圖 ........................................................................................ 26 中斷保護服務程序流程圖 .................................................................... 27 子程序模塊 : ...................................................................................................... 27 軟 起動 子程序 ........................................................................................ 27 鍵值處理子程序流程圖 ........................................................................ 29 PID 子程序 流程圖 .................................................................................. 30 子程序流程圖 ........................................................................................ 31 結束語 ............................................................................................................................ 32 參考文獻 ....................................................................................................................... 33 致 謝 ............................................................................................................................ 34 湖南科技大學本科生畢業(yè)設計（論文） 1 第一章 緒論 交流調速的發(fā)展狀況 交流調速技術誕生 1 世紀， 但由于其性能無法與直流調速技術相比，所以過去的直流調速系統(tǒng)一直在電氣傳動領域中占統(tǒng)治地位。 系統(tǒng)的總體結構主要由主回路，驅動電路，光電隔離電路， 觸發(fā)器 ， 電壓電流檢測保護電路， STC89C51RC 單片機，