摘 要:交流異步電動(dòng)機(jī)因其成本低，高可靠性和少維護(hù)等優(yōu)點(diǎn)在各種工業(yè)領(lǐng)域中得到廣泛的應(yīng)用。但是其起動(dòng)過(guò)程中會(huì)產(chǎn)生很大的起動(dòng)電流，過(guò)大的電流會(huì)加速電動(dòng)機(jī)的絕緣老化，大大降低電動(dòng)機(jī)的使用壽命，導(dǎo)致大量的能量被消耗。大的電流還會(huì)造成較大的線路壓降，從而影響接在同一電網(wǎng)上的其它電氣設(shè)備正常工作。因此，如何改善異步電動(dòng)機(jī)的起動(dòng)性能，具有重要的經(jīng)濟(jì)價(jià)值。
本設(shè)計(jì)從理論上分析了三相異步電動(dòng)機(jī)起動(dòng)過(guò)程，設(shè)計(jì)了一種基于單片機(jī)控制的高壓異步電動(dòng)機(jī)軟起動(dòng)裝置，對(duì)控制器的電路構(gòu)成及軟件進(jìn)行了分析。主電路由三組反并聯(lián)晶閘管和接觸器組成，將開關(guān)變壓器的高壓繞組串聯(lián)在主電路中，而低壓繞組并聯(lián)接上一對(duì)反并聯(lián)晶閘管。通過(guò)控制晶閘管的觸發(fā)角可以連續(xù)改變開關(guān)變壓器高壓繞組的電壓，從而連續(xù)改變電動(dòng)機(jī)的定子端電壓，實(shí)現(xiàn)高壓電動(dòng)機(jī)的軟起動(dòng)，并通過(guò)鍵盤與顯示電路分別顯示出電壓，電流，頻率等參數(shù)。同時(shí)解決了晶閘管的耐壓?jiǎn)栴}。

關(guān)鍵詞 : 軟起動(dòng)器 調(diào)壓電路 單片機(jī) 異步電動(dòng)機(jī)
Abstract: AC induction motor has low cost, high reliability and low maintenance advantages. So they are used in various industrial fields widely. The starting process will generate a large starting current. The current can accelerate the aging of motor insulation, reducing the life of the motor greatly. And then it will be result in the consumed of the energy Large current will result in the greater pressure droping, affecting the power line connected to the same work to other electrical equipment. Therefore, It has an important economic value in how to improve the starting performance of induction motor.
The design analyzed the theory of three-phase asynchronous motor starting process and design a microcontroller-based control of high voltage induction motor soft start device, the controller circuits and software for the analysis. The main circuit consists of three anti-parallel thyristors and contacts form, the switch transformer high-voltage windings in the main circuit, and low-voltage winding and a pair of anti-parallel connected thyristors. Controlling the thyristor firing angle can be changed continuously switching voltage transformer high voltage winding, which continuously change the motor stator terminal voltage, high-voltage motor soft start, and through the keyboard and display circuit, respectively, showing voltage, current, frequency and other parameters . At the same time the pressure to solve the problem of thyristor.

Key words: soft starter voltage regulator circuit microcontroller induction motor simulation
摘 要.................................................................................................I
Abstract.............................................................................................II

第1章 緒論..........................................................................................1
1.1課程研究的目的及意義.......................................................................1
1.2軟起動(dòng)技術(shù)的發(fā)展現(xiàn)狀.......................................................................2
1.2.1國(guó)內(nèi)發(fā)展?fàn)顩r.................................................................................4
1.2.2國(guó)外發(fā)展?fàn)顩r.................................................................................4
1.3本文主要研究工作..............................................................................5
第2章 晶閘管軟起動(dòng)技術(shù)原理....................................................................6
2.1三相異步電動(dòng)機(jī)起動(dòng)過(guò)程.....................................................................6
2.2晶閘管軟起動(dòng)技術(shù)原理........................................................................8
2.2.1基本原理闡述.................................................................................8
2.2.2晶閘管參數(shù)選擇..............................................................................9
2.3異步電動(dòng)機(jī)傳統(tǒng)起動(dòng)方式及原理............................................................10
2.3.1直接起動(dòng)........................................................................................10
2.3.2減壓起動(dòng).........................................................................................11
2.3.3星-三角形起動(dòng)..................................................................................11
2.3.4自耦變壓器起動(dòng)................................................................................11
2.4軟起動(dòng)的起動(dòng)方式.................................................................................13
2.5軟起動(dòng)的原理及分析..............................................................................15
2.5.1晶閘管調(diào)壓原理..................................................................................15
2.5.2晶閘管端電壓與觸發(fā)角之間的關(guān)系..........................................................16
2.6小結(jié)....................................................................................................18
第3章 系統(tǒng)硬件電路的設(shè)計(jì)...........................................................................19
3.1系統(tǒng)總體框圖的設(shè)計(jì)...........................................................................