电机的选型计算课件.ppt

1、电机的选型计算 Michel COUPATM8 lex15 Lexium SizerI关于机械的背景知识关于机械的背景知识II再生能量再生能量 III电机选型计算的步骤电机选型计算的步骤IV施耐德伺服的计算施耐德伺服的计算V练习练习 Michel COUPATM8 lex15 Lexium SizerI关于机械的背景知识关于机械的背景知识单位单位机械公式机械公式 惯量的计算惯量的计算运动学运动学摩擦摩擦惯量的比例惯量的比例 II再生能量再生能量III电机选型计算的步骤电机选型计算的步骤IV施耐德伺服的计算施耐德伺服的计算V练习练习 Michel COUPATM8 lex15 Lexium Si

2、zer Michel COUPATM8 lex15 Lexium Sizern 3 个基本单位个基本单位:国际单位制国际单位制(SI)质量质量:m单位单位:千克千克(kg)长度长度:l单位单位:米米(m)时间时间:t单位单位:秒秒(s)_推导单位推导单位:角度角度:单位单位:弧度弧度(rad)360=2radrlrl Michel COUPATM8 lex15 Lexium Sizern运动学运动学线速度线速度:l t-1单位单位:米每秒米每秒(m/s or m.s-1)角速度角速度:t-1单位单位:弧度每秒弧度每秒(rd/s or s-1):dxvdtDVt瞬时速度平均速度 :tddt瞬时速

3、度平均速度Wx in mWt in sWD in mWt in sW in radians60N2 W in rd/sWN in rpm Michel COUPATM8 lex15 Lexium Sizern运动学运动学:线加速度线加速度:l t-2单位单位:米每秒平方米每秒平方(m/s/s or m.s-2)角加速度角加速度:t-2单位单位:弧度每平方秒弧度每平方秒(rad.s-2 or s-2):v:tdvdt瞬时加速度平均加速度d:dt:t 瞬间加速度平均加速度Wv in m/sWt in sWt in sW in rd/s Michel COUPATM8 lex15 Lexium Si

4、zern 运动学运动学:力力:m l t-单位单位:牛顿牛顿(N)力等于质量与加速度的乘积力等于质量与加速度的乘积:F=m 重量重量 W:m l t-单位单位:牛顿牛顿(N)W=m.g (g:重力加速度重力加速度=9,81m/s)力矩力矩 M:m l t-单位单位:牛米牛米(Nm)力与长度的乘积力与长度的乘积:M=F r (力与长度的方向垂直时力与长度的方向垂直时)运动力矩运动力矩:M=J (J:转动惯量转动惯量 kg.m)能量能量:m l t-单位单位:焦耳焦耳(J)力与位移的乘积力与位移的乘积:E=F L或转矩与角度的乘积或转矩与角度的乘积:E=M rF Michel COUPATM8 l

5、ex15 Lexium SizertEP WE in JouleWt in sWF in NewtonWV in m/sWM in NmW in rad/sn 运动学运动学:功率功率:m l t-3单位单位:Watt(W)1 W=1 J/s*直线运动直线运动:P=F v*角运动角运动 :P=M Michel COUPATM8 lex15 Lexium Sizer质量质量,重量重量,力力:单位单位:磅磅(lb)盎司盎司(oz):1 lb=16 oz 长度长度:单位单位:英寸英寸(in)1英尺英尺(ft)=12 英寸英寸 -1 码码(yd)=3英尺英尺 时间时间:单位单位:秒秒(s)线速度线速度:

6、单位单位:英寸每秒英寸每秒(in/s)线加速度线加速度:单位单位:英寸每平方秒英寸每平方秒(in/s)力矩力矩:单位单位:英寸磅英寸磅(in.lb)惯量惯量:单位单位:英寸磅平方秒英寸磅平方秒(in.lb.s)Michel COUPATM8 lex15 Lexium Sizer重量重量:1 pound(lb)=453,59237 g=0,45359237 kg=4,44822 N 长度长度:1 inch(in)=2,54 cm=0,0254 m力矩力矩:1 inch pound(in.lb)=0,1130234 Nm惯量惯量:1 inch pound second square(in.lb.s

7、)=0,112961 kg.m重力加速度重力加速度:g=386 in/s=32,12 ft/s=9,81 m/s Michel COUPATM8 lex15 Lexium Sizer Michel COUPATM8 lex15 Lexium Sizern 直线运动直线运动:n 角度运动角度运动:ctions)(with friFJMJMMP tt t 2 2000221FvPmFxvv tvxtv tx 22120002 Michel COUPATM8 lex15 Lexium SizerWE in JoulesWJ in kg.m2W in rad/sn 直线运动直线运动:n 转动转动:2C

8、IN JE212CINv mE21WE in JoulesWm in kgWv in m/s Michel COUPATM8 lex15 Lexium Sizer Michel COUPATM8 lex15 Lexium Sizern 密度密度:单位单位:千克每立方米千克每立方米(Kg/m3)磅每立方英尺磅每立方英尺(lb/in3)某个体积承载的重量取决于构成的材料某个体积承载的重量取决于构成的材料.常见材料的密度常见材料的密度:VmWm:质量 in Kg or lbWV:体积 in m3 or in3W :密度 in Kg/m3 or lb/in3o 钢钢:7750 Kg/m30,286 l

9、b/in3o 铝铝:2720 Kg/m30,098 lb/in3o 黄铜黄铜:8170 Kg/m30,295 lb/in3o 紫铜紫铜:8910 Kg/m30,322 lb/in3o 塑料塑料:1110 Kg/m3 0,040 lb/in3 Michel COUPATM8 lex15 Lexium SizerwhLVVm(if h and W nMAX.n Nominal torque:MN Mt+Mf.Michel COUPATM8 lex15 Lexium Sizer Michel COUPATM8 lex15 Lexium SizerELEMENTS TO DEFINE:n Accele

10、ration torque:MACC=J.From all the data of the kinematics,calculate the torque to reach the acceleration requirements.n Friction torque Mf.Calculate or evaluate if possible the friction torque on the axis.FIRST APPROACH OF DRIVE CHOICE:n Maximal torque:MMAX MACC+Mf.The maximal torque available on the

11、 motor is defined by the maximal current available on the drive.Michel COUPATM8 lex15 Lexium Sizer Michel COUPATM8 lex15 Lexium Sizern From the first motor-drive association defined previously,it is necessary to check its appropriateness with the working cycle.nPlot speed versus time and torque vers

12、us time for the entire motion cycle.Michel COUPATM8 lex15 Lexium Sizern Calculating the average speed.cycleiiavgTtnn2nniin Calculating the equivalent thermal torque.cycleiithTtMMDuring the acceleration and deceleration times:Michel COUPATM8 lex15 Lexium Sizer M(Nm)n(rpm)MthnavgIntermittent regionCon

13、tinuous regionnavgMthABn Compare the calculation results with the Torque curve of motor:Case A:Motor well sized for the working cycle.Case B:Choose another motor with higher continuous torque.Michel COUPATM8 lex15 Lexium Sizer Michel COUPATM8 lex15 Lexium Sizern From machine data calculate the inert

14、ia ratio between load and motor.If this ratio is to high(see typical ratio below)Either change eventually the kinematics(i.e.by using Gearbox),or use another motor with higher inertia.or both.Make a new sizing with the new inertia data.n Typical ratios of load to motor inertia can be:from 1:1 to 3:1

15、-for robotic applications.from 4:1 to 7:1-for machine tool type applications.from 8:1 to 10:1-for other factory automation applications.n More practically,we can advise to limit the inertia ratio to:5:1 for dynamical and accurate machines.10:1 for standard machines.Higher if we only need stop accura

16、cy without time cycle constraint.Michel COUPATM8 lex15 Lexium Sizer Michel COUPATM8 lex15 Lexium Sizern Check if an external braking resistance is required:See chapter II.Michel COUPATM8 lex15 Lexium SizerIMechanical reminderIIEnergy regenerated IIIDifferent stages of sizingIVSchneider Motion SizerV

17、Exercises Michel COUPATM8 lex15 Lexium Sizern Help to choose the right motor-drive association from:Kinematics definition.Velocity profile of the cycle.n Help to choose the best ratio of inertia between motor and load.Michel COUPATM8 lex15 Lexium Sizern Choose the units of works:Metric units.US stan

18、dards(Anglo-Saxon units).Michel COUPATM8 lex15 Lexium Sizern Belt-PulleyHELP!Kinematics parameters to define Load Inertian Conveyorn Diskn Gearboxn Lead screwn Rack-Pinionn Rotary tablen Nip rollKinematics:Michel COUPATM8 lex15 Lexium Sizern Definition of the velocity profile of cycle work:Michel CO

19、UPATM8 lex15 Lexium Sizern Select the best criteria to choose the motor:Stability:select the best load/motor inertia match.Dynamic:select the smallest motor.Michel COUPATM8 lex15 Lexium Sizern To define the limits of value for selecting motors:Michel COUPATM8 lex15 Lexium SizerList of motors selecte

20、dInertia ratio:Message“Gearbox?”is noted if inertia ratio 10 Michel COUPATM8 lex15 Lexium Sizer Here is indicated ifan external brakingr e s i s t o r i s requested Michel COUPATM8 lex15 Lexium Sizern Lexium sizer creates a professional looking application report for every axes.Michel COUPATM8 lex15

21、 Lexium Sizern Select the best inertia ratio can induce to choose an higher motor than the cycle requests.Michel COUPATM8 lex15 Lexium SizerIMechanical reminderIIEnergy regenerated IIIDifferent stages of sizingIV Schneider Motion SizerV Exercises Michel COUPATM8 lex15 Lexium Sizer Machine Data:-Moto

22、r pulley(mp):D:14 cm m:3,6 Kg -Gearbox pulley(gp):D:21 cm m:10 Kg -Belt mass:50 g -Gearbox Ratio:8,25 Inertia(gb):0,021 Kg.m Efficiency:98%-Main pulley(md):D:20 cm m:9,2 Kg -Load mass:700 Kg -Belt conveyor mass:4,5 Kg-Coefficient friction:0,1 Michel COUPATM8 lex15 Lexium Sizer1-1:Calculate the inert

23、ia reflected to the motor shaft.1-2:Calculate the resistant torque to the motor shaft.1-2-1 Horizontal axis1-2-2 Vertical axis1-2-3 Axis 451-2-4 Check the calculation with Schneider Sizer.Michel COUPATM8 lex15 Lexium SizerTriangular Profile:-Move distance:6 m -Move time:5 s -Dwell time:0 s 1a-1:Calc

24、ulate the thermal torque for horizontal axis.1a-2:Check the calculation with Schneider Sizer.Michel COUPATM8 lex15 Lexium SizerTrapezoidal Profile:-Move distance:6 m -Move time:5 s -Dwell time:0 s 1b-1:Check the calculation with Schneider Sizer.Michel COUPATM8 lex15 Lexium SizerTrapezoidal Profile:-

25、Move Speed:1 m/s -Move time:5 s -Accel./Decel time:0,2 s -Dwell time:0 s 1c-1:Calculate the thermal torque for horizontal axis.1c-2:Check the calculation with Schneider Sizer.Michel COUPATM8 lex15 Lexium SizerTrapezoidal Profile:-Move distance:6 m -Move time:3600 s -Accel./Decel time:60 s -Dwell tim

26、e:0 s 1d-1:Check the calculation with Schneider Sizer.Michel COUPATM8 lex15 Lexium SizerLead screw:L:Screw length=1,4 mDs:Screw diameter=0,04 mp:Screw pitch=0,01 m/rev:Friction coefficient=0,2:Screw efficiency=0,95Load:mL:Load+table mass=500 kgCoupling:mL:Coupling mass=1 kgDc:External diameter=0,06

27、mHorizontal axis=0JMJS,pmLJCFfrFP,Fg Michel COUPATM8 lex15 Lexium Sizer2-1:Calculate the inertia reflected to the motor shaft.2-2:Calculate the resistant torque to the motor shaft.2-2-1 Horizontal axis2-2-2 Check the calculation with Schneider Sizer.Michel COUPATM8 lex15 Lexium SizerTrapezoidal Prof

28、ile:-Axis speed:15 m/mn -Move time:1,2 s -Dwell time:0,3 s 2a-1:Calculate the thermal torque for horizontal axis.2a-2:Check the calculation with Schneider Sizer.人有了知识，就会具备各种分析能力，明辨是非的能力。所以我们要勤恳读书，广泛阅读，古人说“书中自有黄金屋。”通过阅读科技书籍，我们能丰富知识，培养逻辑思维能力；通过阅读文学作品，我们能提高文学鉴赏水平，培养文学情趣；通过阅读报刊，我们能增长见识，扩大自己的知识面。有许多书籍还能培养我们的道德情操，给我们巨大的精神力量，鼓舞我们前进。