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diff --git a/A Textbook of Electrical Technology AC and DC Machines/chapter26.ipynb b/A Textbook of Electrical Technology AC and DC Machines/chapter26.ipynb new file mode 100644 index 00000000..0690f646 --- /dev/null +++ b/A Textbook of Electrical Technology AC and DC Machines/chapter26.ipynb @@ -0,0 +1,1741 @@ +{ + "metadata": { + "name": "", + "signature": "sha256:e71bef33b0871199556c73182ec6cd28497a9d9d16612973a23ee2cceda4b35b" + }, + "nbformat": 3, + "nbformat_minor": 0, + "worksheets": [ + { + "cells": [ + { + "cell_type": "heading", + "level": 1, + "metadata": {}, + "source": [ + "Chapter 26: D.C. Generators" + ] + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.3, Page Number:912" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "i=450#A\n", + "v=230#v\n", + "rs=50#ohm\n", + "ra=.03#ohm\n", + "\n", + "#calculations\n", + "ish=v/rs\n", + "ia=i+ish\n", + "va=ia*ra\n", + "E=v+va\n", + "\n", + "#result\n", + "print \"e.m.f. generated in the armature= \",E,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "e.m.f. generated in the armature= 243.62 V\n" + ] + } + ], + "prompt_number": 2 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.4, Page Number:913" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "i=50#A\n", + "v=500#v\n", + "rs=250#ohm\n", + "ra=.05#ohm\n", + "rseries=0.03#ohm\n", + "b=1#V\n", + "\n", + "#calculations\n", + "ish=v/rs\n", + "ia=i+ish\n", + "vs=ia*rseries\n", + "va=ia*ra\n", + "vb=ish*b\n", + "E=v+va+vs+vb\n", + "\n", + "#result\n", + "print \"generated voltage in the armature= \",E,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "generated voltage in the armature= 506.16 V\n" + ] + } + ], + "prompt_number": 2 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.5, Page Number:913" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "i=30#A\n", + "v=220#v\n", + "rs=200#ohm\n", + "ra=.05#ohm\n", + "rseries=0.30#ohm\n", + "b=1#V\n", + "\n", + "#calculations\n", + "vs=i*rseries\n", + "vshunt=v+vs\n", + "ish=vshunt/v\n", + "ia=i+ish\n", + "vb=b*2\n", + "E=v+vs+vb+(ia*ra)\n", + "\n", + "#result\n", + "print \"generated voltage in the armature= \",E,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "generated voltage in the armature= 232.552045455 V\n" + ] + } + ], + "prompt_number": 1 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.6, Page Number:913" + ] + }, + { + "cell_type": "code", + "collapsed": true, + "input": [ + "#variable declaration\n", + "v=230.0#v\n", + "i=150.0#A\n", + "rs=92.0#ohm\n", + "rseries=0.015#ohm\n", + "rd=0.03#ohm(divertor)\n", + "ra=0.032#ohm\n", + "\n", + "#calculations\n", + "ish=v/rs\n", + "ia=i+ish\n", + "sdr=(rd*rseries)/(rd+rseries)\n", + "tr=ra+sdr\n", + "vd=ia*tr\n", + "Eg=v+vd\n", + "tp=Eg*ia\n", + "pl=(ia*ia*ra)+(ia*ia*sdr)+(v*ish)+(v*i)\n", + "\n", + "#resuts\n", + "print \"i) Induced e.m.f.= \",Eg,\" V\"\n", + "print \"ii)Total power generated= \",tp,\" W\"\n", + "print \"iii)Distribution of the total power:\"\n", + "print \" power lost in armature= \", ia*ia*ra\n", + "print \"power lost in series field and divider= \", ia*ia*sdr\n", + "print \"power dissipated in shunt winding= \", v*ish\n", + "print \"power delivered to load= \", v*i\n", + "print \" ------------\"\n", + "print \"Total= \", pl" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "i) Induced e.m.f.= 236.405 V\n", + "ii)Total power generated= 36051.7625 W\n", + "iii)Distribution of the total power:\n", + " power lost in armature= 744.2\n", + "power lost in series field and divider= 232.5625\n", + "power dissipated in shunt winding= 575.0\n", + "power delivered to load= 34500.0\n", + " ------------\n", + "Total= 36051.7625\n" + ] + } + ], + "prompt_number": 1 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.7, Page Number:914" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=300000.0#w\n", + "v=600.0#v\n", + "sr=75.0#ohm\n", + "abr=0.03#ohm\n", + "cr=0.011#ohm\n", + "rseries=0.012#ohm\n", + "dr=0.036#ohm\n", + "\n", + "#calculatons\n", + "io=p/v#output current\n", + "ish=v/sr\n", + "ia=io+ish\n", + "sdr=(rseries*dr)/(rseries+dr)\n", + "tr=abr+cr+sdr\n", + "vd=ia*tr\n", + "va=v+vd\n", + "pg=va*ia\n", + "W=pg/1000\n", + "\n", + "#result\n", + "print \"Voltage generatedby the armature= \",va,\" V\"\n", + "print \"Power generated by the armature= \",W, \"kW\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Voltage generatedby the armature= 625.4 V\n", + "Power generated by the armature= 317.7032 kW\n" + ] + } + ], + "prompt_number": 11 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.8, Page Number:915" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "#variable declaration\n", + "phi=7*math.pow(10,-3)\n", + "z=51*20\n", + "a=p=4\n", + "n=1500#r.p.m\n", + "\n", + "#calculations\n", + "Eg=(phi*z*n*p)/(a*60)\n", + "\n", + "#result\n", + "print \"Voltage generated= \",Eg,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Voltage generated= 178.5 V\n" + ] + } + ], + "prompt_number": 13 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.9, Page Number:916" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=a=8\n", + "phi=0.05#Wb\n", + "n=1200#rpm\n", + "N=500#armature conductor\n", + "\n", + "#calculations\n", + "E=phi*(n/60)*(p/a)*N\n", + "\n", + "#result\n", + "print \"e.m.f generated= \",E,\" V\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "e.m.f generated= 500.0 V\n" + ] + } + ], + "prompt_number": 22 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.10, Page Number:916" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "v=127#v\n", + "vt=120#v(terminal voltage)\n", + "r=15#ohms\n", + "i1=8.47#A\n", + "ra=0.02#ohms\n", + "fi=8#A\n", + "\n", + "#calculations\n", + "Eg=v+(i1*ra)\n", + "ia=(Eg-vt)/ra\n", + "il=ia-fi\n", + "\n", + "#result\n", + "print \"Load current \",il,\" A\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Load current 350.47 A\n" + ] + } + ], + "prompt_number": 24 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.11(a), Page Number:917" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=8\n", + "z=778\n", + "n=500\n", + "ra=0.24\n", + "rl=12.5\n", + "r=250\n", + "v=250\n", + "a=2\n", + "#calculations\n", + "il=v/rl\n", + "si=v/r\n", + "ai=il+si\n", + "emf=v+(ai*ra)\n", + "phi=(emf*60*a)/(p*z*n)\n", + "\n", + "#result\n", + "print \"armature current= \",ai,\" A\"\n", + "print \"induced e.m.f.= \",emf,\" V\"\n", + "print \"flux per pole= \",round(phi*1000,2),\" mWb\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "armature current= 21.0 A\n", + "induced e.m.f.= 255.04 V\n", + "flux per pole= 9.83 mWb\n" + ] + } + ], + "prompt_number": 2 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.11(b), Page Number:916" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=a=4\n", + "P=5000.0#w\n", + "P2=2500.0#W\n", + "v=250.0#v\n", + "ra=0.2#ohm\n", + "r=250.0#ohm\n", + "z=120\n", + "N=1000#rpm\n", + "\n", + "#calculations\n", + "gc=P/v\n", + "li=P2/v\n", + "ti=gc+li\n", + "fc=1\n", + "ai=ti+fc\n", + "ard=ai*ra\n", + "emf=v+ard+2\n", + "phi=(emf*60*a)/(p*z*N)\n", + "ac_perparralelpath=ai/p\n", + "\n", + "#result\n", + "print \"Flux per pole= \",phi*1000,\" mWb\"\n", + "print \"Armature current per parallel path= \",ac_perparralelpath,\" A\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Flux per pole= 129.1 mWb\n", + "Armature current per parallel path= 7.75 A\n" + ] + } + ], + "prompt_number": 5 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.12, Page Number:918" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "i=200.0#A\n", + "v=125.0#V\n", + "n1=1000#rpm\n", + "n2=800#rpm\n", + "ra=0.04#ohm\n", + "bd=2.0#V(brush drop)\n", + "\n", + "#calculations\n", + "R=v/i\n", + "E1=v+(i*ra)+bd\n", + "E2=(E1*n2)/n1\n", + "il=(E2-bd)/0.675\n", + "\n", + "#result\n", + "print \"Load current when speed drops to 800 r.p.m.= \",round(il,2),\" A\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Load current when speed drops to 800 r.p.m.= 157.04 A\n" + ] + } + ], + "prompt_number": 8 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.13, Page Number:918" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "#variable declaration\n", + "p=4\n", + "n=900 #rpm\n", + "V=220#V\n", + "E=240#V\n", + "ra=0.2#ohm\n", + "phi=10#mWb\n", + "N=8\n", + "\n", + "#calculations\n", + "ia=(E-V)/ra\n", + "Z=(E*600*2)/(phi*math.pow(10,-3)*n*p)\n", + "#since there ae 8 turns in a coil,it means there are 16 active conductor\n", + "number_of_coils=Z/16\n", + "\n", + "#result\n", + "print \"armature current= \",ia,\" A\"\n", + "print \"number of coils= \",number_of_coils" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "armature current= 100.0 A\n", + "number of coils= 500.0\n" + ] + } + ], + "prompt_number": 6 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.14, Page Number:919" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "V=120.0#V\n", + "ra=0.06#ohm\n", + "rs=25#ohm\n", + "rsw=0.04#ohm(series winding)\n", + "il=100.0#A\n", + "#i)Long shunt\n", + "ish=V/rs\n", + "ia=il+ish\n", + "vd=ia*rsw\n", + "vda=ia*ra\n", + "E=V+vd+vda\n", + "\n", + "print \"Induced e.m.f. when the machine is connected to long shunt= \",E,\" V\"\n", + "print \"Armature current when the machine is connected to long shunt=\",ia,\" A\"\n", + "\n", + "#i)Short shunt\n", + "vds=il*rsw\n", + "vs=V+vds\n", + "ish=vs/rs\n", + "ia=il+ish\n", + "vd=ia*rsw\n", + "vda=ia*ra\n", + "E=V+vd+vda\n", + "\n", + "print \"Induced e.m.f. when the machine is connected to short shunt= \",E,\" V\"\n", + "print \"Armature current when the machine is connected to short shunt=\",ia,\" A\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Induced e.m.f. when the machine is connected to long shunt= 130.48 V\n", + "Armature current when the machine is connected to long shunt= 104.8 A\n", + "Induced e.m.f. when the machine is connected to short shunt= 130.496 V\n", + "Armature current when the machine is connected to short shunt= 104.96 A\n" + ] + } + ], + "prompt_number": 3 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.15, Page Number:920" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=25000.0#W\n", + "V=500.0#V\n", + "ra=0.03#ohm\n", + "rs=200.0#ohm\n", + "rseries=0.04#ohm\n", + "vb=1.0#V\n", + "n=1200#rpm\n", + "phi=0.02#Wb\n", + "\n", + "#calculations\n", + "i=p/V\n", + "ish=V/rs\n", + "ia=i+ish\n", + "p=4\n", + "vds=ia*rseries\n", + "vda=ia*ra\n", + "vdb=vb*2\n", + "E=V+vds+vda+vdb\n", + "Z=(E*60*4)/(phi*n*p)\n", + "\n", + "#result\n", + "print \"The e.m.f. generated= \",E,\" V\"\n", + "print \"The number of conductors=\",Z" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "The e.m.f. generated= 505.675 V\n", + "The number of conductors= 1264.1875\n" + ] + } + ], + "prompt_number": 15 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.16, Page Number:920" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=4\n", + "n=750#rpm\n", + "e=240.0#V\n", + "z=792\n", + "phi=0.0145#Wb\n", + "\n", + "#calculations\n", + "phi_working=(e*60*2)/(n*z*p)\n", + "lambda_=phi/phi_working\n", + "\n", + "#results\n", + "print \"Leakage coefficient= \",round(lambda_,1)" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Leakage coefficient= 1.2\n" + ] + } + ], + "prompt_number": 9 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.17, Page Number:920" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=a=4\n", + "phi=0.07#Wb\n", + "t=220\n", + "rt=0.004#ohm\n", + "n=900#rpm\n", + "ia=50.0#A\n", + "\n", + "#calculations\n", + "z=2*t\n", + "E=(phi*z*n*p)/(60*a)\n", + "rtotal=t*rt\n", + "r_eachpath=rtotal/p\n", + "ra=r_eachpath/a\n", + "vda=ia*ra\n", + "V=E-vda\n", + "\n", + "#result\n", + "print \"Terminal Voltage= \",V, \" V\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Terminal Voltage= 459.25 V\n" + ] + } + ], + "prompt_number": 27 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.18, Page Number:920" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=a=4\n", + "phi=0.07#Wb\n", + "t=220\n", + "rturn=0.004#ohm\n", + "rs=100.0#ohm\n", + "rsc=0.02#ohm\n", + "n=900#rpm\n", + "ia=50.0#A\n", + "\n", + "#calculations\n", + "z=2*t\n", + "E=(phi*z*n*p)/(60*a)\n", + "ra=0.055#ohm\n", + "ra=ra+rsc\n", + "va=ia*ra\n", + "v=E-va\n", + "ish=v/rs\n", + "i=ia-ish\n", + "output=v*i\n", + "\n", + "#result\n", + "print \"Output= \",round(output/1000,3),\" kW\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Output= 20.813 kW\n" + ] + } + ], + "prompt_number": 15 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.19, Page Number:921" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "n1=1200#rpm\n", + "ia=200#A\n", + "v=125#V\n", + "n2=1000#rpm\n", + "ra=0.04#ohm\n", + "vb=2#V\n", + "\n", + "#calculations\n", + "E1=v+vb+(ia*ra)\n", + "E2=E1*n2/n1*0.8\n", + "\n", + "#results\n", + "print \"Generated e.m.f. when field current is reduced to 80%=\",E2,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Generated e.m.f. when field current is reduced to 80%= 90.0 V\n" + ] + } + ], + "prompt_number": 35 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.20(a), Page Number:921" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=4\n", + "rs=100.0#ohm\n", + "ra=1.0#ohm\n", + "z=378\n", + "phi=0.02#Wb\n", + "rl=10.0#ohm\n", + "n=1000#rpm\n", + "a=2\n", + "\n", + "#calculations\n", + "E=(phi*z*n*p)/(60*a)\n", + "V=(100.0/111.0)*E\n", + "il=V/rl\n", + "P=il*V\n", + "\n", + "#result\n", + "print \"Power absorbed by the load is= \",P,\" W\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Power absorbed by the load is= 5154.12710007 W\n" + ] + } + ], + "prompt_number": 50 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.20(b), Page Number:921" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=a=4\n", + "z=300\n", + "phi=0.1#Wb\n", + "n=1000#rpm\n", + "ra=0.2#rpm\n", + "rf=125#ohm\n", + "il=90#A\n", + "\n", + "#calculations\n", + "E=(phi*z*n*p)/(60*a)\n", + "ifield=E/rf\n", + "ia=ifield+il\n", + "V=E-(ia*ra)\n", + "\n", + "#result\n", + "print \"Terminal voltage= \",V,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Terminal voltage= 481.2 V\n" + ] + } + ], + "prompt_number": 51 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.21(a), Page Number:922" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=6\n", + "n=1200#rpm\n", + "e=250.0#V\n", + "d=350.0#mm\n", + "air_gap=3.0#mm\n", + "al=260.0#mm\n", + "fringing=0.8\n", + "coils=96\n", + "t=3\n", + "\n", + "#calculations\n", + "z=t*coils*2\n", + "a=p*2\n", + "phi=(e*60*a)/(n*z*p)\n", + "di=d+air_gap\n", + "pole_arc=(3.14*di*fringing)/6\n", + "B=phi/(pole_arc*0.000001*al)\n", + "\n", + "#result\n", + "print \"flux per pole= \",phi,\" Wb\"\n", + "print \"effective pole arc lenght= \",pole_arc*0.001,\" m\"\n", + "print \"flux density= \",B,\" T\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "flux per pole= 0.0434027777778 Wb\n", + "effective pole arc lenght= 0.147789333333 m\n", + "flux density= 1.12953862717 T\n" + ] + } + ], + "prompt_number": 57 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.21(b), Page Number:922" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "#variable declaration\n", + "p=a=4\n", + "z=1200\n", + "e=250.0#v\n", + "n=500#rpm\n", + "b=35.0#cm\n", + "ratio=0.7\n", + "lpole=20.0#cm\n", + "\n", + "#calculations\n", + "pole_pitch=(b*3.14)/p\n", + "polearc=ratio*pole_pitch\n", + "pole_area=polearc*lpole\n", + "phi=(e*60*a)/(n*z*p)\n", + "mean_flux=phi/(pole_area*math.pow(10,-4))\n", + " \n", + "#result\n", + "print \"Mean flux density= \",mean_flux,\" Wb/m2\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Mean flux density= 0.649941505265 Wb/m2\n" + ] + } + ], + "prompt_number": 67 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.21(d), Page Number:923" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "i=200.0#A\n", + "v=100.0#V\n", + "ra=0.04#ohm\n", + "rseries=0.03#ohm\n", + "rs=60.0#ohm\n", + "\n", + "#calculations\n", + "va=v+(i*rseries)\n", + "ish=va/rs\n", + "ia=i+ish\n", + "e=va+(ia*ra)\n", + "\n", + "#long shunt\n", + "ishunt=v/rs\n", + "vd=ia*(ra+rseries)\n", + "e2=v+vd\n", + "\n", + "#result\n", + "print \"emf generated(short shunt)\",e,\" V\"\n", + "print \"emf generated(long shunt)\",e2,\" V\"\n", + "\n", + "\n", + "#result\n", + "print " + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "emf generated(short shunt) 114.070666667 V\n", + "emf generated(long shunt) 114.123666667 V\n", + "\n" + ] + } + ], + "prompt_number": 73 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.22, Page Number:923" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "n=1000#rpm\n", + "w=20000.0#W\n", + "v=220.0#v\n", + "ra=0.04#ohm\n", + "rs=110.0#ohm\n", + "rseries=0.05#ohm\n", + "efficiency=.85\n", + "\n", + "#calculations\n", + "il=w/v\n", + "i_f=v/rs\n", + "ia=il+i_f\n", + "ip=w/efficiency#input power\n", + "total_loss=ip-w\n", + "copper_loss=(ia*ia*(ra+rseries))+(i_f*i_f*rs)\n", + "ironloss=total_loss-copper_loss\n", + "omega=2*3.14*n/60\n", + "T=ip/omega\n", + "\n", + "#omega\n", + "print \"Copper loss= \",copper_loss,\" W\"\n", + "print \"Iron and friction loss= \",ironloss,\" W\"\n", + "print \"Torque developed by the prime mover= \",T,\"Nw-m\"\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Copper loss= 1216.88892562 W\n", + "Iron and friction loss= 2312.52283909 W\n", + "Torque developed by the prime mover= 224.803297115 Nw-m\n" + ] + } + ], + "prompt_number": 75 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.23, Page Number:928" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declartaion\n", + "power=10000.0#W\n", + "v=250.0#V\n", + "p=a=6\n", + "n=1000.0#rpm\n", + "z=534\n", + "cu_loss=0.64*1000#W\n", + "vbd=1.0#V\n", + "\n", + "#calculations\n", + "ia=power/v\n", + "ra=cu_loss/(ia*ia)\n", + "E=v+(ia*ra)+vbd\n", + "phi=(E*60*a)/(n*z*p)\n", + "\n", + "#result\n", + "print \"flux per pole= \",phi*1000,\" mWb\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "flux per pole= 30.0 mWb\n" + ] + } + ], + "prompt_number": 25 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.24(a), Page Number:928" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "i=195#A\n", + "pd=250#V\n", + "ra=0.02#ohm\n", + "rsh=50#ohm\n", + "p=250#W\n", + "strayloss=950#W\n", + "#calculations\n", + "ish=pd/rsh\n", + "ia=i+ish\n", + "vda=ia*ra\n", + "E=pd+vda\n", + "cu_loss=(ia*ia*ra)+(pd*ish)\n", + "output_prime=(pd*i)+strayloss+cu_loss\n", + "power_a=output_prime-strayloss\n", + "neu_m=(power_a/output_prime)\n", + "neu_e=(pd*i)/((pd*i)+cu_loss)\n", + "neu_c=(pd*i)/output_prime\n", + "\n", + "#result\n", + "print \"a)e.m.f. generated= \",E,\" V\"\n", + "print \" b)Cu losses= \",cu_loss,\" W\"\n", + "print \" c)output of prime mover= \",output_prime,\" W\"\n", + "print \" d)mechanical efficiency= \",neu_m*100,\" %\"\n", + "print \" electrical efficiency= \",neu_e*100,\" %\"\n", + "print \" commercial efficiency= \",neu_c*100,\" %\"\n", + "\n" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "a)e.m.f. generated= 254.0 V\n", + " b)Cu losses= 2050.0 W\n", + " c)output of prime mover= 51750.0 W\n", + " d)mechanical efficiency= 98.1642512077 %\n", + " electrical efficiency= 95.9645669291 %\n", + " commercial efficiency= 94.2028985507 %\n" + ] + } + ], + "prompt_number": 30 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.24(b), Page Number:929" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "v=500.0#V\n", + "i=5.0#A\n", + "ra=0.15#ohm\n", + "rf=200.0#ohm\n", + "il=40.0#A\n", + "\n", + "#calculations\n", + "output=v*il\n", + "total_loss=(v*i*0.5)+((il+i*0.5)*(il+i*0.5)*ra)+(v*i*0.5)\n", + "efficiency=output/(output+total_loss)\n", + "\n", + "#result\n", + "print \"Efficiency= \",efficiency*100,\" %\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Efficiency= 87.8312542029 %\n" + ] + } + ], + "prompt_number": 39 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.25, Page Number:929" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "#variable declaration\n", + "i=196#A\n", + "v=220#V\n", + "stray_loss=720#W\n", + "rsh=55#ohm\n", + "e=0.88\n", + "\n", + "#calculations\n", + "output=v*i\n", + "inpute=output/e\n", + "total_loss=inpute-output\n", + "ish=v/rsh\n", + "ia=i+ish\n", + "cu_loss=v*ish\n", + "constant_loss=cu_loss+stray_loss\n", + "culoss_a=total_loss-constant_loss\n", + "ra=culoss_a/(ia*ia)\n", + "I=math.sqrt(constant_loss/ra)\n", + "\n", + "#result\n", + "print \"Load curent corresponding to maximum efficiency\",I,\" A\" " + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Load curent corresponding to maximum efficiency 122.283568103 A\n" + ] + } + ], + "prompt_number": 1 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.26, Page Number:929" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "n=1000#rpm\n", + "p=22*1000#w\n", + "v=220#V\n", + "ra=0.05#ohm\n", + "rsh=110#ohm\n", + "rseries=0.06#ohm\n", + "efficiency=.88\n", + "\n", + "#calculations\n", + "ish=v/rsh\n", + "I=p/v\n", + "ia=ish+I\n", + "vdseries=ia*rseries\n", + "cu_loss=(ia*ia*ra)+(ia*ia*rseries)+(rsh*ish*ish)\n", + "total_loss=(p/efficiency)-p\n", + "strayloss=total_loss-cu_loss\n", + "T=(p/efficiency*60)/(2*3.14*n)\n", + "\n", + "#result\n", + "print \"a)cu losses= \",cu_loss,\" W\"\n", + "print \"b)iron and friction loss= \",strayloss,\" W\"\n", + "print \"c)Torque exerted by the prime mover= \",T,\" N-m\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "a)cu losses= 1584.44 W\n", + "b)iron and friction loss= 1415.56 W\n", + "c)Torque exerted by the prime mover= 238.853503185 N-m\n" + ] + } + ], + "prompt_number": 7 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.27, Page Number:930" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=4\n", + "i=20#A\n", + "r=10#ohm\n", + "ra=0.5#ohm\n", + "rsh=50#ohm\n", + "vdb=1#V(voltage drop per brush)\n", + "\n", + "#calculations\n", + "v=i*r\n", + "ish=v/rsh\n", + "ia=i+ish\n", + "E=v+(ia*ra)+(2*vdb)\n", + "totalpower=E*ia\n", + "output=v*i\n", + "efficiency=output/totalpower\n", + "\n", + "#result\n", + "print \"induced e.m.f.= \",E,\" V\"\n", + "print \"efficiency= \",efficiency*100,\" %\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "induced e.m.f.= 214.0 V\n", + "efficiency= 77.8816199377 %\n" + ] + } + ], + "prompt_number": 2 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.28, Page Number:930" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "v=240#V\n", + "i=100#A\n", + "ra=0.1#ohm\n", + "rseries=0.02#ohm\n", + "ri=0.025#ohm\n", + "rsh=100#ohm\n", + "ironloss=1000#W\n", + "frictionloss=500#W\n", + "\n", + "#calculations\n", + "output=v*i\n", + "totalra=ra+rseries+ri\n", + "ish=v/rsh\n", + "ia=i+ish\n", + "copperloss=ia*ia*totalra\n", + "shculoss=ish*v\n", + "total_loss=copperloss+ironloss+frictionloss+shculoss\n", + "efficiency=output/(output+total_loss)\n", + "\n", + "#result\n", + "print \"F.L. efficiency of the machine= \",efficiency*100,\" %\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "F.L. efficiency of the machine= 87.3089843128 %\n" + ] + } + ], + "prompt_number": 25 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.29, Page Number:930" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from sympy.solvers import solve\n", + "from sympy import Symbol\n", + "#variable declaration\n", + "A=Symbol('A')\n", + "B=Symbol('B')\n", + "ironloss=8#kW\n", + "r=0.25#reduction in speed\n", + "n_ironloss=5#kW\n", + "\n", + "#calculations\n", + "ans=solve([ironloss-(A*1+B*1**2),n_ironloss-(A*(1-r)+B*(1-r)**2)],[A,B])\n", + "wh=ans[A]\n", + "we=ans[B]\n", + "wh2=ans[A]*0.5\n", + "we2=ans[B]*0.5**2\n", + "\n", + "#result\n", + "print \"i)full speed:\"\n", + "print \"Wh=\",round(wh,3),\"kW\"\n", + "print \"We=\",round(we,3),\"kW\"\n", + "print \"ii)half speed:\"\n", + "print \"Wh=\",round(wh2,3),\"kW\"\n", + "print \"We=\",round(we2,3),\"kW\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "i)full speed:\n", + "Wh= 2.667 kW\n", + "We= 5.333 kW\n", + "ii)half speed:\n", + "Wh= 1.333 kW\n", + "We= 1.333 kW\n" + ] + } + ], + "prompt_number": 7 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.30, Page Number:931" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "import math\n", + "from sympy.solvers import solve\n", + "from sympy import Symbol\n", + "#variable declaration\n", + "N=Symbol('N')\n", + "n=1000.0#rpm\n", + "wh=250.0#w\n", + "we=100.0#w\n", + "\n", + "#calculations\n", + "A=wh/(n/60)\n", + "B=we/((n/60)**2)\n", + "new_loss=(wh+we)/2\n", + "ans=solve([new_loss-A*N-B*(N**2)],[N])\n", + "\n", + "#result\n", + "print \"Speed at which total loss will be halved=\",ans[1],\"r.p.s\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Speed at which total loss will be halved= (9.50045787200216,) r.p.s\n" + ] + } + ], + "prompt_number": 29 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.31, Page Number:931" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "output=10.0*1000#W\n", + "v=240.0#V\n", + "ra=0.6#ohm\n", + "rsh=160.0#ohm\n", + "mechcoreloss=500.0#W\n", + "culoss=360.0#W\n", + "\n", + "#calculations\n", + "ish=v/rsh\n", + "i=output/v\n", + "ia=ish+i\n", + "culossa=ia*ia*ra\n", + "totalloss=culoss+mechcoreloss+culossa\n", + "inputp=output+totalloss\n", + "efficiency=output/inputp\n", + "\n", + "#result\n", + "print \"Power required= \",inputp*0.001,\" kW\"\n", + "print \"efficinecy= \",efficiency*100,\" %\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "Power required= 11.9780166667 kW\n", + "efficinecy= 83.486275552 %\n" + ] + } + ], + "prompt_number": 30 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.32, Page Number:932" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=110*1000#W\n", + "v=220#V\n", + "ra=0.01#ohm\n", + "rse=0.002#ohm\n", + "rsh=110#ohm\n", + "\n", + "#calculations\n", + "il=p/v\n", + "ish=v/rsh\n", + "ia=il+ish\n", + "E=v+ia*(ra+rse)\n", + "\n", + "#result\n", + "print \"induced emf= \",E,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "induced emf= 226.024 V\n" + ] + } + ], + "prompt_number": 31 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.33 Page Number:932" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=4\n", + "E=216.0#V\n", + "n=600.0#rpm\n", + "slots=144\n", + "con=6\n", + "n2=500.0#rpm\n", + "\n", + "#calculations\n", + "z=con*slots\n", + "a=p\n", + "phi=(E*60*a)/(n*z*p)\n", + "a=2\n", + "armatureE=(phi*z*n2*p)/(60*a)\n", + "\n", + "#result\n", + "print \"the armature emf= \",armatureE,\" V\"" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "the armature emf= 360.0 V\n" + ] + } + ], + "prompt_number": 34 + }, + { + "cell_type": "heading", + "level": 2, + "metadata": {}, + "source": [ + "Example Number 26.34 Page Number:933" + ] + }, + { + "cell_type": "code", + "collapsed": false, + "input": [ + "#variable declaration\n", + "p=4\n", + "r=0.15#ohm\n", + "\n", + "#calculations\n", + "ar=p*r\n", + "\n", + "#result\n", + "print \"armature resistance=\",ar" + ], + "language": "python", + "metadata": {}, + "outputs": [ + { + "output_type": "stream", + "stream": "stdout", + "text": [ + "armature resistance= 0.6\n" + ] + } + ], + "prompt_number": 30 + }, + { + "cell_type": "code", + "collapsed": false, + "input": [], + "language": "python", + "metadata": {}, + "outputs": [] + } + ], + "metadata": {} + } + ] +}
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