三相异步电动机的工作原理及结构

三相异步电动机的工作原理及结构 一(旋转磁场的产生 旋转磁场:极性和大小不变且以一定转速旋转的磁场。 旋转磁场的产生:对称三相绕组流过对称三相电流，产生圆形旋转磁通势和旋转磁场。 ,120三相对称绕组:三套数据相同，空间(沿定子内圆)互差电角度的绕组组成三相对称绕组，图4-1为最简单的三相对称绕组。 三相对称电流: (1)瞬时表达式: ,,i,Icos,ti,Icos(,t,120)i,Icos(,t,240)AmBmCm (2)电流变化曲线 (图4-2) 旋转磁场:规定电流为正时，从首端出，分析几个特定瞬间: 1,(a),t,0;i,I;i,i,,IAmBCm2 1,(b),t,120;i,I;i,i,,IBmCAm2 1,(c),t,240;i,I;i,i,,ICmABm2 1,(d),t,360;i,I;i,i,,IAmBCm2 document management as a breakthrough, and constantly improve the content, active in the application. Government information between the provincial and municipal governments all passed through a network of offices, and six counties (districts) have complete decision-making service system and through dial-up internetworking is realized with the city, the City Planning Commission and other 10 departments has been one of the first to achieve a single network with the city. On the Government's website, focus on strengthening the management and operation of the site, update the website in a timely manner, strengthening the network resource sharing. At present, nearly 700 municipal government website page, updated news more than more than 6,000. Not long ago, China International e-government technology and application Conference was carried out in the country, "survey of best public services Government website" activities in Pingliang city people's Government website in five Northwestern provinces (districts) ranked second, ranked first in the Gansu province. V, infrastructure has made new breakthroughs In 2002 smooth completed organ office building of construction, and decoration and relocation of based Shang, we according to organ construction general planning, demolition hospital within old room 37 between, transformation garden 3600 square meters, new plant lawn 2700 square meters, planting 由图4-1分析可知:(1)对称三相电流通过对称三相绕组时，必然会产生一个大小不变，转速一定的磁场。(2)由于电流变化一个周期，磁场转过一对磁极，所以旋转磁场的转速: f601n,0rminp () 称为同步转速。 (一)工作原理 定子三相对称绕组，接通三相对称电源，流过三相对称电流，产生旋转磁场(电生磁)，切割转子导体，感应电势和电流(磁变生电)，载流导体在磁场中受到电磁力的作用，形成电磁转矩(电磁生力)，使转子朝着旋转磁场旋转的方向旋转。 (二)转差率与运动状态 nn0一般情况下，转子的转速总是略低于同步转速“异步”之名由此而来，转差，，n,n0是异步电机运行的必要条件，将转差与同步转速之比的百分值称为转差率S: n,n0s,n0 转差率是异步电机的一个基本参量，不同的数值范围反映不同的运行状态。 0,n,n,0,s,1.0 电动机的运行状态 n,n,s,0.0 发电机运行状态 n,0,s，0. 电磁制动状态 三相异步电机的结构:图4-3表示绕线转子三相异步电动机的结构，由定子和转子组成。 document management as a breakthrough, and constantly improve the content, active in the application. Government information between the provincial and municipal governments all passed through a network of offices, and six counties (districts) have complete decision-making service system and through dial-up internetworking is realized with the city, the City Planning Commission and other 10 departments has been one of the first to achieve a single network with the city. On the Government's website, focus on strengthening the management and operation of the site, update the website in a timely manner, strengthening the network resource sharing. At present, nearly 700 municipal government website page, updated news more than more than 6,000. Not long ago, China International e-government technology and application Conference was carried out in the country, "survey of best public services Government website" activities in Pingliang city people's Government website in five Northwestern provinces (districts) ranked second, ranked first in the Gansu province. V, infrastructure has made new breakthroughs In 2002 smooth completed organ office building of construction, and decoration and relocation of based Shang, we according to organ construction general planning, demolition hospital within old room 37 between, transformation garden 3600 square meters, new plant lawn 2700 square meters, planting (一)定子 定子铁芯:导磁和嵌放定子三相绕组;0.5mm硅钢片冲制涂漆叠压而成;内圆均匀开槽;槽形有半闭口 ;半开口和开口槽三种; 适用于不同的电机 定子绕组: 电路 ;绝缘导线绕制线圈;由若干线圈按一定规律连接成三相对称绕组; 交流电机的定子绕组称为电枢绕组 机座: 支撑和固定作用; 铸铁或钢板焊接 (二)转子 转子铁芯: 导磁和嵌放转子绕组; 0.5mm硅钢片; 外圆开槽 转子绕组: 分为笼型和绕线型两种 笼型绕组: 电路 ;铸铝或铜条(图4—4或图4—5); 优缺点 绕线型绕组: 对称三相绕组; 星接; 集电环 (图4—6);优缺点 气隙: 气隙大小的影响; 中小型电机的气隙为0.2~2mm ?4-2三相异步电动机的铭牌数据 一(型号 二(铭牌数据(额定数据) document management as a breakthrough, and constantly improve the content, active in the application. Government information between the provincial and municipal governments all passed through a network of offices, and six counties (districts) have complete decision-making service system and through dial-up internetworking is realized with the city, the City Planning Commission and other 10 departments has been one of the first to achieve a single network with the city. On the Government's website, focus on strengthening the management and operation of the site, update the website in a timely manner, strengthening the network resource sharing. At present, nearly 700 municipal government website page, updated news more than more than 6,000. Not long ago, China International e-government technology and application Conference was carried out in the country, "survey of best public services Government website" activities in Pingliang city people's Government website in five Northwestern provinces (districts) ranked second, ranked first in the Gansu province. V, infrastructure has made new breakthroughs In 2002 smooth completed organ office building of construction, and decoration and relocation of based Shang, we according to organ construction general planning, demolition hospital within old room 37 between, transformation garden 3600 square meters, new plant lawn 2700 square meters, planting P,KWn1. 1. 额定功率 。 额定运行时输出的机械功率 U,VN2. 2. 额定电压 I,AN3. 3. 额定电流 f,HNZ4. 4. 额定频率 n,rminN5. 5. 额定转速 铭牌上还应标示定子绕组接法、绝缘等级(允许温升)、绕线型异步电动机还应标示转 子额定电动势及额定电流。 ?4-3三相异步电动机的定子绕组 三相定子绕组的作用和要求。 一(交流绕组的基本知识和基本量 (一)电角度与机械角度 电角度=P×机械角度 (二)线圈 一匝或多匝，首端和末端 (三)节距 一个线圈两边所跨定子圆周上的距离，用y表示 一般以槽数计，节距应1 Q1,,2py,,y,,,11近似等于极距，时为整距，时为短距，其中。 ,(四)槽距角 相邻两槽之间的电角度(一个槽所在距离相应的电角度) ,p，360,,Q1 (五)每级每相槽数q 每一个极下每相绕组所占的槽数 Q1q,2pm 二、单层绕组 Q,24p,21单层绕组:每个槽内只放一个线圈边。线圈数目等于槽数的一半，，的 实例 说明 关于失联党员情况说明岗位说明总经理岗位说明书会计岗位说明书行政主管岗位说明书 单层绕组的构成。 (一)计算极距和节距 Q241,,,,6y,,,62p2，21 (整距) (二)计算每极每相槽数 Q241q,,,22pm2，3，2 (三)绘制绕组展开图(图4—7) 1(画24根并行短线，代表24个槽，编上槽号(图4—7a)) document management as a breakthrough, and constantly improve the content, active in the application. Government information between the provincial and municipal governments all passed through a network of offices, and six counties (districts) have complete decision-making service system and through dial-up internetworking is realized with the city, the City Planning Commission and other 10 departments has been one of the first to achieve a single network with the city. On the Government's website, focus on strengthening the management and operation of the site, update the website in a timely manner, strengthening the network resource sharing. At present, nearly 700 municipal government website page, updated news more than more than 6,000. Not long ago, China International e-government technology and application Conference was carried out in the country, "survey of best public services Government website" activities in Pingliang city people's Government website in five Northwestern provinces (districts) ranked second, ranked first in the Gansu province. V, infrastructure has made new breakthroughs In 2002 smooth completed organ office building of construction, and decoration and relocation of based Shang, we according to organ construction general planning, demolition hospital within old room 37 between, transformation garden 3600 square meters, new plant lawn 2700 square meters, planting 0q,2602(按进行分相。相带:每个极下属于同一相的槽所占的区域称为相带。相 q,2带:每个极距内有3个相带。本例共有3×4=12个相带。每个相带有个槽。相带分配:A,z,B,x,C,y 。 y,13(按6组成一个线圈，而后以同样方法组成属于A相的所有线圈。 4(按q=2连出A相绕组的p个线圈组。 5(按所需并联支路数a，将p个线圈组串联、并联或串并联，连成一相(A相)绕组。 6(按同样方法连出B相和C相绕组。 单层绕组还可联成链式、交叉式、同心式等 单层绕组的优点是线圈数少，嵌线方便，无层间绝缘，槽的利用率高。缺点是磁通势和电动势的波形较差，影响电动机的性能，一般用于功率在10KW以下的小型电机。 三、双层绕组 双层绕组:每个槽内放两个线圈边，一个边放在上层，一个放下层。线圈数等于槽数。 Q,36p,21例: 双层叠绕组 Q361,,,,92p41、计算极距 y,812、绕组节距 选 document management as a breakthrough, and constantly improve the content, active in the application. Government information between the provincial and municipal governments all passed through a network of offices, and six counties (districts) have complete decision-making service system and through dial-up internetworking is realized with the city, the City Planning Commission and other 10 departments has been one of the first to achieve a single network with the city. On the Government's website, focus on strengthening the management and operation of the site, update the website in a timely manner, strengthening the network resource sharing. At present, nearly 700 municipal government website page, updated news more than more than 6,000. Not long ago, China International e-government technology and application Conference was carried out in the country, "survey of best public services Government website" activities in Pingliang city people's Government website in five Northwestern provinces (districts) ranked second, ranked first in the Gansu province. V, infrastructure has made new breakthroughs In 2002 smooth completed organ office building of construction, and decoration and relocation of based Shang, we according to organ construction general planning, demolition hospital within old room 37 between, transformation garden 3600 square meters, new plant lawn 2700 square meters, planting Q361q,,,32pm2，2，33、每极每相槽数 0600,,,20q槽距角: 4、画展开图。如图4-8a)所示，图中并联支路数a=1，最少a=4。 圆形接线图，如图4-8b)所示，也可用连接顺序表。如图4-9，4-10所示。 document management as a breakthrough, and constantly improve the content, active in the application. Government information between the provincial and municipal governments all passed through a network of offices, and six counties (districts) have complete decision-making service system and through dial-up internetworking is realized with the city, the City Planning Commission and other 10 departments has been one of the first to achieve a single network with the city. On the Government's website, focus on strengthening the management and operation of the site, update the website in a timely manner, strengthening the network resource sharing. At present, nearly 700 municipal government website page, updated news more than more than 6,000. Not long ago, China International e-government technology and application Conference was carried out in the country, "survey of best public services Government website" activities in Pingliang city people's Government website in five Northwestern provinces (districts) ranked second, ranked first in the Gansu province. V, infrastructure has made new breakthroughs In 2002 smooth completed organ office building of construction, and decoration and relocation of based Shang, we according to organ construction general planning, demolition hospital within old room 37 between, transformation garden 3600 square meters, new plant lawn 2700 square meters, planting 绕线型异步电动机转子绕组不宜采用叠绕组，而采用波绕组。以减小线圈组间连接线，便于平衡。波绕组的相带划分与槽号分配与叠绕组相同。连接规则是把所有同一极性下属于同一相的线圈按照一定次序串联起来组成一组;再把所有另一极下属于同一相的线圈按照一定次序串联起来组成一组，最后将这两组串联或并联联接构成一相绕组。另一相绕组的构成与之相同。如图4—11所示。 document management as a breakthrough, and constantly improve the content, active in the application. Government information between the provincial and municipal governments all passed through a network of offices, and six counties (districts) have complete decision-making service system and through dial-up internetworking is realized with the city, the City Planning Commission and other 10 departments has been one of the first to achieve a single network with the city. On the Government's website, focus on strengthening the management and operation of the site, update the website in a timely manner, strengthening the network resource sharing. At present, nearly 700 municipal government website page, updated news more than more than 6,000. Not long ago, China International e-government technology and application Conference was carried out in the country, "survey of best public services Government website" activities in Pingliang city people's Government website in five Northwestern provinces (districts) ranked second, ranked first in the Gansu province. V, infrastructure has made new breakthroughs In 2002 smooth completed organ office building of construction, and decoration and relocation of based Shang, we according to organ construction general planning, demolition hospital within old room 37 between, transformation garden 3600 square meters, new plant lawn 2700 square meters, planting