摘 要：隨著交流電動機軟啟動技術(shù)的快速發(fā)展，實際對其要求越來越高，三相異步電動機的起動電流高達額定電流的5～8倍，對電網(wǎng)造成較大干擾，尤其在工業(yè)領(lǐng)域中的重載起動，有時可能對設(shè)備安全構(gòu)成嚴重威脅，所以軟起動技術(shù)被廣泛應用。
本文主要通過單片機ATmega16的控制，對晶閘管的導通角進行控制，串接電源與被控電機之間的三相反并聯(lián)晶閘管及其電路控制回路控制三相晶閘管的導通角使被控電機的輸入電壓、電流按不同的要求而變化，可以實現(xiàn)電壓以及電流的要求，基于交流電動機的原理、軟啟動器的原理，實現(xiàn)外圍電路的控制工作。通過單片機對六路觸發(fā)脈沖控制，模數(shù)、數(shù)模轉(zhuǎn)換通過A/D、D/A，通過相位移動控制電流以及電壓。

關(guān)鍵詞：異步電動機 軟啟動器 晶閘管 模數(shù)轉(zhuǎn)換

Abstract：AC motor soft start technology with the rapid development of，Increasing demands of its actual,Three-phase asynchronous motor currents up to rated current of 5 to 8 times，Cause greater interference on the power grid，Especially in the industrial field of heavy-duty starting，May sometimes pose a serious threat to the safety equipment，So soft start technology is widely used，In this paper, the control by microcontroller AT89S52，Conduction angle of thyristor control。
Electrical power supply and charged in series of three contrast between the thyristor and the parallel three-phase thyristor circuit control loop control of the motor conduction angle of the accused input voltage and current changes according to different requirements，Can achieve the required voltage and current，AC motors based on the principle of the principle of the soft starter，To achieve control of the external circuit，Microcontroller on the six-way through the trigger pulse control module, digital to analog conversion through the A / D, D / A，By phase shift control of current and voltage

Key words ： Asynchronous motor Soft starter SCR ADC

目　錄
摘 要 ..........................................................................................I
Abstract......................................................................................II

第1章 緒論................................................................................. 1
1.1概述......................................................................................1
1.2異步電動機的啟動問題..............................................................1
1.3國內(nèi)外發(fā)展狀況.......................................................................2
1.3.1國內(nèi)發(fā)展狀況.......................................................................2
1.3.2國外發(fā)展狀況.......................................................................3
1.4電力電子軟啟動方法 ................................................................3
1.5本課題研究目的.......................................................................5
第2章 軟啟動器的基礎(chǔ)理論.............................................................6
2.1軟起動器的啟動過程分析...........................................................6
2.2常用的啟動方式.......................................................................6
2.3軟起動器常用的幾種停車方式.....................................................9
2.4本章小結(jié)................................................................................9
第3章 硬件電路設(shè)計.....................................................................10
3.1 系統(tǒng)總體框圖 ........................................................................10
3.2電力電子軟啟動器的主電路........................................................11
3.3單片機的選擇..........................................................................12
3.4同步電壓檢測電路.....................................................................13
3.5電流檢測電路...........................................................................14
3.6電壓檢測電路...........................................................................14
3.7鍵盤與顯示電路........................................................................15
3.8觸發(fā)電路.................................................................................16
3.9通信電路.................................................................................16
3.10繼電器驅(qū)動電路......................................................................17
3.11電源電路的設(shè)計......................................................................18
3.12本章小結(jié)...............................................................................19
第4章 系統(tǒng)軟件設(shè)計.......................................................................20
4.1主程序設(shè)計..............................................................................20
4.2定時顯示中斷服務程序設(shè)計.........................................................21
4.3外中斷服務程序設(shè)計 .................................................................21
4.4 A/D轉(zhuǎn)換中斷服務程序設(shè)計........................................................22
4.5定時觸發(fā)脈沖算角計和控制命令程序設(shè)計....................................