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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 5 - REPRESENTATION AND PERFORMANCE OF SHORT AND MEDIUM TRANSMISSION LINES"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E1 - Pg 128"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Voltage at sending end,Regulation,Transmission Efficiency\n",
      "import math\n",
      "#Given data :\n",
      "P=1100.##kW\n",
      "VR=11.*1000.##V\n",
      "pf=0.8##power factor\n",
      "R=2.##ohm\n",
      "X=3.##ohm\n",
      "I=P*1000./VR/pf##A\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1.-cos_fi_r**2)#\n",
      "VS=math.sqrt((VR*cos_fi_r+I*R)**2.+(VR*sin_fi_r+I*X)**2.)##V\n",
      "print '%s %.f' %(\"Voltage at sending end(V)\",VS)#\n",
      "Reg=(VS-VR)/VR*100.##%\n",
      "print '%s %.3f' %(\"Regulation\",Reg)#\n",
      "LineLoss=I**2.*R/1000.##kW\n",
      "Eta_T=P*100./(P+LineLoss)##%\n",
      "print '%s %.2f' %(\"Transmission Efficiency(%)\",Eta_T)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Voltage at sending end(V) 11426\n",
        "Regulation 3.873\n",
        "Transmission Efficiency(%) 97.24\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E2 - Pg 128"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Transmission Efficiency(%)\n",
      "import math \n",
      "#Given data :\n",
      "R=0.4##ohm\n",
      "X=0.4##ohm \n",
      "P=2000.##kVA\n",
      "pf=0.8##power factor\n",
      "VL=3000.##V\n",
      "VR=VL/math.sqrt(3.)##V\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2.)#\n",
      "I=P*1000./3./VR##A\n",
      "VS=VR+I*(R*cos_fi_r+X*sin_fi_r)##V\n",
      "Reg=(VS-VR)/VR*100.##%\n",
      "print '%s %.2f' %(\"% Regulation\",Reg)#\n",
      "LineLoss=3.*I**2.*R/1000.##kW\n",
      "Pout=P*cos_fi_r##kW\n",
      "Eta_T=Pout*100./(Pout+LineLoss)##%\n",
      "print '%s %.f' %(\"Transmission Efficiency(%)\",Eta_T)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "% Regulation 12.44\n",
        "Transmission Efficiency(%) 90\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E3 - Pg 129"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate \n",
      "import math\n",
      "#Given data :\n",
      "l=15.##km\n",
      "P=5.##MW\n",
      "V=11.##kV\n",
      "f=50.##Hz\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "L=1.1##mH/Km\n",
      "VR=V*1000./math.sqrt(3.)##V\n",
      "I=P*1000./math.sqrt(3.)/V/cos_fi_r##A\n",
      "LineLoss=12./100.*P*10**6##W\n",
      "R=LineLoss/3./I**2##ohm\n",
      "X=2.*math.pi*f*L*10**-3*l##ohm/phase\n",
      "VS=VR+I*(R*cos_fi_r+X*sin_fi_r)##V\n",
      "VSL=math.sqrt(3.)*VS/1000.##KV\n",
      "print '%s %.3f' %(\"Line voltage at sending end(kV)\",VSL)#\n",
      "Reg=(VSL-V)/V*100.##%\n",
      "print '%s %.3f' %(\"% Regulation\",Reg)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Line voltage at sending end(kV) 13.612\n",
        "% Regulation 23.745\n"
       ]
      }
     ],
     "prompt_number": 22
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E4 - Pg 130"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Line voltage at sending end(kV),Sending end pf(lagging),Transmission Efficiency(%),Regulation\n",
      "import math \n",
      "#Given data :\n",
      "l=50.##km\n",
      "S=10000.##kVA\n",
      "pf=0.8##power factor\n",
      "d=1.2*100.##cm\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "V=33000.##Volts\n",
      "VR=V/math.sqrt(3.)##V\n",
      "f=50.##Hz\n",
      "I=S*1000./math.sqrt(3.)/V##A\n",
      "LineLoss=10./100.*S*10.**3*pf##W\n",
      "R=LineLoss/3./I**2##ohm\n",
      "rho=1.73*10**-6##kg/m**3\n",
      "a=rho*l*1000.*100./R##cm**2\n",
      "r=math.sqrt(a/math.pi)##cm\n",
      "L=0.2*math.log(d/r/0.7788)*l##mH\n",
      "X=2*math.pi*f*L*10**-3##ohm\n",
      "VS=VR+I*(R*cos_fi_r+X*sin_fi_r)##V\n",
      "VSL=math.sqrt(3.)*VS/1000.##kV\n",
      "print '%s %.2f' %(\"Line voltage at sending end(kV)\",VSL)#\n",
      "pf_s=(VR*cos_fi_r+I*R)/VS##lagging(sendinf end pf)\n",
      "print '%s %.4f' %(\"Sending end pf(lagging) \",pf_s)#\n",
      "Eta_T=S*pf/(S*pf+LineLoss/1000.)*100.#\n",
      "print '%s %.2f' %(\"Transmission Efficiency(%)\",Eta_T)#\n",
      "Reg=(VSL-V/1000.)/(V/1000.)*100.##%\n",
      "print '%s %.2f' %(\"% Regulation\",Reg)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Line voltage at sending end(kV) 38.32\n",
        "Sending end pf(lagging)  0.7579\n",
        "Transmission Efficiency(%) 90.91\n",
        "% Regulation 16.12\n"
       ]
      }
     ],
     "prompt_number": 23
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E5 - Pg 130"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Resistance per phase(ohm/phase),Inductance per phase(mH/phase)\n",
      "import math \n",
      "#Given data :\n",
      "VRL=30000.##Volts\n",
      "VSL=33000.##Volts\n",
      "f=50.##Hz\n",
      "P=10.*10.**6##W\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "VR=VRL/math.sqrt(3.)##V\n",
      "I=P/math.sqrt(3.)/VRL/pf##A\n",
      "Eta_T=0.96##Efficiency\n",
      "LineLoss=P*(1/Eta_T-1)##W\n",
      "R=LineLoss/3/I**2##ohm/phase\n",
      "print '%s %.1f' %(\"Resistance per phase(ohm/phase)\",R)#\n",
      "VS=VSL/math.sqrt(3.)##V\n",
      "X=(VS-VR-I*R*cos_fi_r)/I/sin_fi_r##V\n",
      "L=X/2./math.pi/f##H/phase\n",
      "print '%s %.f' %(\"Inductance per phase(mH/phase)\",L*1000)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Resistance per phase(ohm/phase) 2.4\n",
        "Inductance per phase(mH/phase) 28\n"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E6 - Pg 131"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Line voltage at load end(volt),Transmission Efficiency(%)\n",
      "import math\n",
      "import numpy\n",
      "from numpy import roots\n",
      "#Given data :\n",
      "l=3.##km\n",
      "P=3000.##KW\n",
      "VSL=11.*10**3##volt\n",
      "R=l*0.4##ohm\n",
      "X=l*0.8##ohm\n",
      "VS=VSL/math.sqrt(3.)##Volts\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "#VS=VR+I*(R*cos_fi_r+X*sin_fi_r)##V\n",
      "I_into_VR=P*1000./3./cos_fi_r##VA\n",
      "#VR**2-VS*VR+I_into_VR*(R*cos_fi_r+X*sin_fi_r)#\n",
      "p=([1, -VS, I_into_VR*(R*cos_fi_r+X*sin_fi_r)])#\n",
      "VR=numpy.roots(p)#\n",
      "VR=VR[0]##taking greater value\n",
      "I=I_into_VR/VR##A\n",
      "VRL=math.sqrt(3.)*VR##volt\n",
      "print '%s %.f' %(\"Line voltage at load end(volt) : \",VRL)#\n",
      "Eta_T=P*1000/(P*1000+3*I**2*R)*100##%\n",
      "print '%s %.1f' %(\"Transmission Efficiency(%) : \",Eta_T)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Line voltage at load end(volt) :  10110\n",
        "Transmission Efficiency(%) :  94.8\n"
       ]
      }
     ],
     "prompt_number": 24
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E7 - Pg 131"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Power output(kW),Power factor at sending end(lagging)\n",
      "import math\n",
      "#Given data :\n",
      "R=5.##ohm/phase\n",
      "X=20.##ohm/phase\n",
      "VSL=46.85##kV\n",
      "VRL=33.##kV\n",
      "VRL=VRL*1000.##v\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "VR=VRL/math.sqrt(3.)##V\n",
      "I=(VSL*1000./math.sqrt(3.)-VR)/(R*cos_fi_r+X*sin_fi_r)##A\n",
      "Pout=math.sqrt(3.)*VRL*I*pf/1000.##kW\n",
      "print '%s %.f' %(\"Power output(kW)\",Pout)#\n",
      "cosfi_s=(VR*pf+I*R)/(VSL*1000/math.sqrt(3.))##power factor\n",
      "print '%s %.3f' %(\"Power factor at sending end(lagging)\",cosfi_s)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Power output(kW) 22853\n",
        "Power factor at sending end(lagging) 0.656\n"
       ]
      }
     ],
     "prompt_number": 9
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E8 - Pg 136"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end power factor(lag),Regulation(%),Transmission Efficiency(%)\n",
      "import math\n",
      "import cmath\n",
      "#Given data :\n",
      "l=80.##km\n",
      "P=15.##MW\n",
      "VR=66.*10**3##Volt\n",
      "R=l*0.3125##ohm\n",
      "X=l*1.##ohm\n",
      "Y=l*17.5*10**-6##S\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "IR=P*10**6/(VR*pf)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "IC=1j*Y*VR##A\n",
      "IS=IR+IC##A\n",
      "print '%s %.1f %s %.2f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS)*180/math.pi)#\n",
      "VS=VR+IS*(R+1j*X)##volt\n",
      "print '%s %.f %s %.2f' %(\"Sending end voltage(V), magnitude is \",abs(VS),\" and angle in degree is \",cmath.phase(VS)*180/math.pi)#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fis=math.cos(fi_s)##sending end pf\n",
      "print '%s %.2f' %(\"Sending end power factor(lag) : \",cos_fis)#\n",
      "Reg=(abs(VS)-VR)/VR*100##%\n",
      "print '%s %.1f' %(\"Regulation(%) :  \",Reg)#\n",
      "LineLoss=abs(IS)**2*R/1000.##kW\n",
      "print '%s %.1f' %(\"Line Losses in kW : \",LineLoss)#\n",
      "Eta_T=P*1000/(P*1000+LineLoss)*100##%\n",
      "print '%s %.2f' %(\"Transmission Efficiency(%) : \",Eta_T)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end current(A), magnitude is  240.3  and angle in degree is  -18.95\n",
        "Sending end voltage(V), magnitude is  79598  and angle in degree is  11.77\n",
        "Sending end power factor(lag) :  0.86\n",
        "Regulation(%) :   20.6\n",
        "Line Losses in kW :  1443.6\n",
        "Transmission Efficiency(%) :  91.22\n"
       ]
      }
     ],
     "prompt_number": 67
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E9 - Pg 137"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end line voltage(Volt) ,Regulation(%),Transmission Efficiency(%)\n",
      "import math\n",
      "import cmath\n",
      "#Given data :\n",
      "l=100.##km\n",
      "P=20.##MW\n",
      "VRL=66.*10**3##volt\n",
      "f=50.##Hz\n",
      "R=10.##ohm\n",
      "L=111.7*10**-3##H\n",
      "C=0.9954*10**-6##F\n",
      "pf=0.8##power factor\n",
      "X=2.*math.pi*f*L##ohm\n",
      "Y=2.*math.pi*f*C##S\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "VR=VRL/math.sqrt(3.)##volt\n",
      "IR=P*10**6/(math.sqrt(3.)*VRL*pf)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "Z=R+1j*X##ohm\n",
      "Vdash=VR+1./2.*IR*Z##Volt\n",
      "IC=Vdash*1j*Y##A\n",
      "IS=IR+IC##A\n",
      "VS=Vdash+1./2.*IS*Z##Volt\n",
      "VSL=abs(VS)*math.sqrt(3.)##Volt\n",
      "print '%s %.f' %(\"Sending end line voltage(Volt) :\",VSL)#\n",
      "Reg=(VSL-VRL)/VRL*100.##%\n",
      "print '%s %.2f' %(\"Regulation(%) :  \",Reg)#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fi_s=math.cos(fi_s)##sending end pf\n",
      "Eta_T=math.sqrt(3.)*VRL*abs(IR)*cos_fi_r/(math.sqrt(3)*VSL*abs(IS)*cos_fi_s)*100##%\n",
      "print '%s %.1f' %(\"Transmission Efficiency(%) : \",Eta_T)#\n",
      "#Ans is not accurate in the book.\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end line voltage(Volt) : 77071\n",
        "Regulation(%) :   16.77\n",
        "Transmission Efficiency(%) :  93.5\n"
       ]
      }
     ],
     "prompt_number": 27
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E10 - Pg 138"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end line voltage(kV),Regulation(%),Transmission Efficiency(%)  \n",
      "import math\n",
      "import cmath\n",
      "#Given data :\n",
      "l=200.##km\n",
      "P=50.##MVA\n",
      "VRL=132.*10**3.##Volt\n",
      "f=50.##Hz\n",
      "R=l*0.15##ohm\n",
      "X=l*0.50##ohm\n",
      "Y=l*2.*10**-6##mho\n",
      "pf=0.85##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "IR=P*10**6/(math.sqrt(3.)*VRL)##A\n",
      "Z=R+1j*X##ohm\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "Vdash=VR+1/2*IR*Z##Volt\n",
      "IC=Vdash*1j*Y##A\n",
      "IS=IR+IC##A\n",
      "print '%s %.2f %s %.2f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS)*180/math.pi)#\n",
      "VS=Vdash+1/2*IS*Z##Volt\n",
      "VSL=abs(VS)*math.sqrt(3)##Volt\n",
      "print '%s %.2f' %(\"Sending end line voltage(kV) :\",VSL/1000)#\n",
      "Reg=(VSL-VRL)/VRL*100##%\n",
      "print '%s %.2f' %(\"Regulation(%) :  \",Reg)#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fi_s=math.cos(fi_s)##sending end pf\n",
      "Eta_T=math.sqrt(3.)*VRL*abs(IR)*cos_fi_r/(math.sqrt(3)*VSL*abs(IS)*cos_fi_s)*100##%\n",
      "print '%s %.2f' %(\"Transmission Efficiency(%) : \",Eta_T)#\n",
      "#Ans is wrong in the book.Angle of VS is calculated wrong leads to wrong answers.\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end current(A), magnitude is  204.28  and angle in degree is  -24.50\n",
        "Sending end line voltage(kV) : 132.00\n",
        "Regulation(%) :   0.00\n",
        "Transmission Efficiency(%) :  100.00\n"
       ]
      }
     ],
     "prompt_number": 65
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E11 - Pg 139"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end power factor(lag)\n",
      "import math\n",
      "import cmath\n",
      "#Given data :\n",
      "S=1.*10**3##kVA\n",
      "pf=0.71##power factor\n",
      "VRL=22.*10**3##Volt\n",
      "f=50.##Hz\n",
      "R=15.##ohm\n",
      "L=0.2##H\n",
      "C=0.5*10**-6##F\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "IR=S*10.**3/VRL##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "X=2.*math.pi*f*L##ohm\n",
      "#Z=sqrt(R**2+X**2)##ohm\n",
      "Z=R+1j*X##ohm\n",
      "Y=2.*math.pi*f*C##S\n",
      "ICR=1./2.*1j*Y*VRL##A\n",
      "IL=IR+ICR##A\n",
      "VS=VRL+IL*Z##Volt\n",
      "print '%s %.f %s %.2f' %(\"Sending end voltage(Volt), magnitude is \",abs(VS),\" and angle in degree is \",cmath.phase(VS))#\n",
      "ICS=1./2.*1j*Y*VS##A\n",
      "IS=IL+ICS##A\n",
      "print '%s %.3f %s %.2f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS))#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fi_s=math.cos(fi_s)##sending end pf\n",
      "print '%s %.3f' %(\"Sending end power factor(lag) : \",cos_fi_s)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end voltage(Volt), magnitude is  24437  and angle in degree is  0.06\n",
        "Sending end current(A), magnitude is  42.874  and angle in degree is  -0.72\n",
        "Sending end power factor(lag) :  0.706\n"
       ]
      }
     ],
     "prompt_number": 31
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E12 - Pg 139"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end line to line voltage(kV)\n",
      "import math\n",
      "#Given data :\n",
      "P=50.*10**6##W\n",
      "f=50.##Hz\n",
      "l=150.##km\n",
      "pf=0.8##power factor\n",
      "VRL=110.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "R=0.1*l##ohm\n",
      "XL=0.5*l##ohm\n",
      "Z=R+1j*XL##ohm\n",
      "IR=P/(math.sqrt(3)*VRL*pf)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "Y=3.*10**-6*l##S\n",
      "ICR=1./2.*1j*Y*VR##A\n",
      "IL=IR+ICR##A\n",
      "VS=VR+IL*Z##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.3f' %(\"Sending end line to line voltage(kV) :\",VSL/1000.)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end line to line voltage(kV) : 143.562\n"
       ]
      }
     ],
     "prompt_number": 32
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E13 - Pg 140"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end line to line voltage(kV),Sending end power factor(lag)\n",
      "import math\n",
      "import cmath\n",
      "#Given data :\n",
      "f=50.##Hz\n",
      "l=30.##km\n",
      "Z=40.+1j*125##ohm\n",
      "Y=10**-3##mho\n",
      "P=50.*10**6##W\n",
      "VRL=220.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3)##Volt\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "IR=P/(math.sqrt(3.)*VRL*pf)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "ICR=1./2.*1j*Y*VR##A\n",
      "IL=IR+ICR##A\n",
      "VS=VR+IL*Z##Volt\n",
      "VSL=math.sqrt(3)*abs(VS)##Volt\n",
      "print '%s %.2f ' %(\"Sending end line to line voltage(kV) :\",VSL/1000)#\n",
      "IS=IL+1./2.*1j*Y*VS##A\n",
      "print '%s %.2f %s %.1f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS)*180/math.pi)#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fis=math.cos(fi_s)##sending end pf\n",
      "print '%s %.3f' %(\"Sending end power factor(lag) : \",cos_fis)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end line to line voltage(kV) : 238.07 \n",
        "Sending end current(A), magnitude is  128.15  and angle in degree is  15.1\n",
        "Sending end power factor(lag) :  0.988\n"
       ]
      }
     ],
     "prompt_number": 63
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E14 - Pg 141"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end line to line voltage(kV)\n",
      "import math \n",
      "#Given data :\n",
      "f=50.##Hz\n",
      "l=30.##km\n",
      "Z=40.+1j*125.##ohm\n",
      "Y=10**-3##mho\n",
      "P=50.*10**6##W\n",
      "VRL=220.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "IR=P/(math.sqrt(3.)*VRL*pf)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "ICR=1./2.*1j*Y*VR##A\n",
      "IL=IR+ICR##A\n",
      "VS=VR+IL*Z##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end line to line voltage(kV) :\",VSL/1000.)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end line to line voltage(kV) : 238.07\n"
       ]
      }
     ],
     "prompt_number": 16
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E15 - Pg 141"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end line voltage(kV),Sending end power factor(lag),Transmission Efficiency(%)\n",
      "import math\n",
      "import cmath\n",
      "#Given data :\n",
      "f=50.##Hz\n",
      "l=100.##km\n",
      "P=50.*10**6##W\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "VRL=132.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "R=0.1*l##ohm\n",
      "XL=0.3*l##ohm\n",
      "Z=R+1j*XL##ohm\n",
      "Y=3.*10**-6*l##S\n",
      "IR=P/(math.sqrt(3)*VRL*pf)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "ICR=1/2*1j*Y*VR##A\n",
      "IL=IR+ICR##A\n",
      "VS=VR+IL*Z##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end line voltage(kV) :\",VSL/1000)#\n",
      "ICS=1./2.*1j*Y*VS##A\n",
      "IS=IL+ICS##A\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fi_s=math.cos(fi_s)##sending end pf\n",
      "print '%s %.2f' %(\"Sending end power factor(lag) : \",cos_fi_s*180/math.pi)#\n",
      "Eta_T=math.sqrt(3)*VRL*abs(IR)*cos_fi_r/(math.sqrt(3)*VSL*abs(IS)*cos_fi_s)*100##%\n",
      "print '%s %.3f' %(\"Transmission Efficiency(%) : \",Eta_T)#\n",
      "#answer in book is wrong\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end line voltage(kV) : 144.56\n",
        "Sending end power factor(lag) :  45.03\n",
        "Transmission Efficiency(%) :  95.709\n"
       ]
      }
     ],
     "prompt_number": 61
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E16 - Pg 142"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Line voltage at mid point(kV),Sending end line voltage(kV)\n",
      "import math \n",
      "import cmath\n",
      "#Given data :\n",
      "f=50.##Hz\n",
      "l=10.##km\n",
      "S1=5000.*10**3##VA\n",
      "S2=10000.*10**3##VA\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "pf2=0.7071##power factor\n",
      "cos_fi_r2=pf2#\n",
      "sin_fi_r2=math.sqrt(1-cos_fi_r2**2)#\n",
      "R=0.6*l##ohm\n",
      "XL=1.5*l##ohm\n",
      "VRL=33*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "I1=S1/(math.sqrt(3.)*VRL)##A\n",
      "I1=I1*(cos_fi_r-1j*sin_fi_r)##A\n",
      "Z1=R+1j*XL##ohm\n",
      "VB=VR+I1*Z1##Volt\n",
      "VBL=math.sqrt(3)*abs(VB)##Volt\n",
      "print '%s %.3f' %(\"Line voltage at mid point(kV) : \",VBL/1000)#\n",
      "I2=S2/(math.sqrt(3.)*VBL)##A\n",
      "I2=I2*(cos_fi_r2-1j*sin_fi_r2)##A\n",
      "I=I1+I2##A\n",
      "print '%s %.2f %s %.2f' %(\"Total current(A), magnitude is \",abs(I),\" and angle in degree is \",cmath.phase(I))#\n",
      "Z2=R+1j*XL##ohm\n",
      "VS=VB+I*Z2##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end line voltage(kV) :\",VSL/1000)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Line voltage at mid point(kV) :  35.114\n",
        "Total current(A), magnitude is  251.32  and angle in degree is  -0.74\n",
        "Sending end line voltage(kV) : 41.64\n"
       ]
      }
     ],
     "prompt_number": 34
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E17 - Pg 143"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Power supplied by line A(kW),B(kW)\n",
      "import cmath\n",
      "import math \n",
      "#Given data :\n",
      "P=10.##MWatt\n",
      "pf=0.8##power factor\n",
      "VRL=30.*10**3##Volt\n",
      "R1=5.5##ohm\n",
      "XL1=13.5##ohm\n",
      "R2=6.##ohm\n",
      "XL2=11.##ohm\n",
      "ZA=R1+1j*XL1##ohm\n",
      "ZB=R2+1j*XL2##ohm\n",
      "S=P*10.**3./pf*(math.cos(-36.52*math.pi/180.) + 1j*math.sin(-36.52*math.pi/180.))##kVA\n",
      "SA=S*ZB/(ZA+ZB)##kVA\n",
      "print '%s %.f %s %.3f' %(\"Load supply by line A(kVA), magnitude is \",abs(SA),\" at pf \",cmath.phase(SA))#\n",
      "SB=S*ZA/(ZA+ZB)##kVA\n",
      "print '%s %.f %s %.2f' %(\"Load supply by line B(kVA), magnitude is \",abs(SB),\" and angle in degree is \",cmath.phase(SA))#\n",
      "PA=abs(SA)*(math.cos(cmath.phase(SA)*180/math.pi))##kW\n",
      "print '%s %.2f' %(\"Power supplied by line A(kW) : \",PA)#\n",
      "PB=abs(SB)*(math.cos(cmath.phase(SB)*180/math.pi))##kW\n",
      "print '%s %.2f' %(\"Power supplied by line B(kW) : \",PB)#\n",
      "#Answer is not accurate in the book.\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Load supply by line A(kVA), magnitude is  5787  at pf  -0.698\n",
        "Load supply by line B(kVA), magnitude is  6733  and angle in degree is  -0.70\n",
        "Power supplied by line A(kW) :  -3797.43\n",
        "Power supplied by line B(kW) :  -3546.79\n"
       ]
      }
     ],
     "prompt_number": 36
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E18 - Pg 145"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Percentage rise in voltage\n",
      "import math \n",
      "#Given data :\n",
      "L=200.##km\n",
      "f=50.##Hz\n",
      "omega=2.*math.pi*f##rad/s\n",
      "Rise=omega**2.*L**2.*10.**-8./18.##%\n",
      "print '%s %.2f' %(\"Percentage rise in voltage : \",Rise)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Percentage rise in voltage :  2.19\n"
       ]
      }
     ],
     "prompt_number": 20
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E19 - Pg 151"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Parameter A,B,C,D\n",
      "import math \n",
      "import cmath\n",
      "#Given data :\n",
      "L=80.##km\n",
      "f=50.##Hz\n",
      "Z=(0.15+1j*0.78)*L##ohm\n",
      "Y=(1j*5.*10.**-6)*L##mho\n",
      "A=1.+1./2.*Y*Z##parameter of 3-phase line\n",
      "D=A##parameter of 3-phase line\n",
      "B=Z*(1.+1./4.*Y*Z)##parameter of 3-phase line\n",
      "C=Y##parameter of 3-phase line\n",
      "print (\"Parameter A : \",A)#\n",
      "print (\"Parameter B : \",B)#\n",
      "print (\"Parameter C : \",C)#\n",
      "print (\"Parameter D : \",D)#\n",
      "#Answer of B is wrong in the book.\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "('Parameter A : ', (0.98752+0.0024j))\n",
        "('Parameter B : ', (11.85024+62.02502400000001j))\n",
        "('Parameter C : ', 0.00039999999999999996j)\n",
        "('Parameter D : ', (0.98752+0.0024j))\n"
       ]
      }
     ],
     "prompt_number": 47
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E20 - Pg 151"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Power Input(MW),Transmission Efficiency(%),Sending end power factor(lag)\n",
      "import math \n",
      "import cmath\n",
      "#Given data :\n",
      "Z=200*math.cos(80.*math.pi/180.) + 1j*math.sin(80.*math.pi/180.)##ohm\n",
      "Y=0.0013*math.cos(90.*math.pi/180.) + 1j*math.sin(90.*math.pi/180.)##mho/phase\n",
      "P=80*10**6##W\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "VRL=220.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3)##Volt\n",
      "f=50##Hz\n",
      "IR=P/(math.sqrt(3.)*VRL*pf)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "A=1.+1./2.*Y*Z##parameter of 3-phase line\n",
      "D=A##parameter of 3-phase line\n",
      "B=Z*(1.+1./4.*Y*Z)##parameter of 3-phase line\n",
      "C=Y##parameter of 3-phase line\n",
      "print '%s %.2f %s %.2f' %(\"Parameter A, magnitude is \",abs(A),\" and angle in degree is \",cmath.phase(A)*180/math.pi)#\n",
      "print '%s %.2f %s %.2f' %(\"Parameter B, magnitude is \",abs(B),\" and angle in degree is \",cmath.phase(B)*180/math.pi)#\n",
      "print '%s %.2f %s %.2f' %(\"Parameter C, magnitude is \",abs(C),\" and angle in degree is \",cmath.phase(C)*180/math.pi)#\n",
      "print '%s %.2f %s %.2f' %(\"Parameter D, magnitude is \",abs(D),\" and angle in degree is \",cmath.phase(D)*180/math.pi)#\n",
      "VS=A*VR+B*IR##Volt\n",
      "VSL=math.sqrt(3)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end Line voltage(kV) : \",VSL/1000.)#\n",
      "IS=C*VR+D*IR##A\n",
      "print '%s %.2f %s %.2f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS)*180/math.pi)#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fis=math.cos(fi_s)##sending end pf\n",
      "print '%s %.2f' %(\"Sending end power factor(lag) : \",cos_fis)#\n",
      "Pin=math.sqrt(3.)*VSL*abs(IS)*cos_fis*10**-6##MW\n",
      "print '%s %.2f' %(\"Power Input(MW) : \",Pin)#\n",
      "Eta=P/(Pin*10**6)*100.##%\n",
      "print '%s %.2f' %(\"Transmission Efficiency(%) : \",Eta)#\n",
      "#Answer in book is wrong"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Parameter A, magnitude is  17.37  and angle in degree is  88.33\n",
        "Parameter B, magnitude is  302.79  and angle in degree is  86.66\n",
        "Parameter C, magnitude is  1.00  and angle in degree is  90.00\n",
        "Parameter D, magnitude is  17.37  and angle in degree is  88.33\n",
        "Sending end Line voltage(kV) :  3930.49\n",
        "Sending end current(A), magnitude is  130613.70  and angle in degree is  88.75\n",
        "Sending end power factor(lag) :  1.00\n",
        "Power Input(MW) :  888811.72\n",
        "Transmission Efficiency(%) :  0.01\n"
       ]
      }
     ],
     "prompt_number": 69
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E21 - Pg 152"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end power factor(lag),Power Input(MW),Transmission Efficiency(%)\n",
      "import math \n",
      "import cmath\n",
      "#Given data :\n",
      "P=50.*10**6##VA\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "A=0.98*math.cos(3.*math.pi/180.) + 1j*math.sin(3.*math.pi/180.)##parameter of 3-phase line\n",
      "D=0.98*math.cos(3.*math.pi/180.) + 1j*math.sin(3.*math.pi/180.)##parameter of 3-phase line\n",
      "B=110*math.cos(75.*math.pi/180.) + 1j*math.sin(75.*math.pi/180.)##parameter of 3-phase line\n",
      "C=0.0005*math.cos(80.*math.pi/180.) + 1j*math.sin(80.*math.pi/180.)##parameter of 3-phase line\n",
      "VRL=110.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "IR=P/(math.sqrt(3.)*VRL)##A\n",
      "IR=IR*(cos_fi_r-1j*sin_fi_r)##A\n",
      "VS=A*VR+B*IR##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end Line voltage(kV) : \",VSL/1000.)#\n",
      "IS=C*VR+D*IR##A\n",
      "print '%s %.2f %s %.2f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS)*180/math.pi)#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##\n",
      "cos_fis=math.cos(fi_s)##sending end pf\n",
      "print '%s %.2f' %(\"Sending end power factor(lag) : \",cos_fis)#\n",
      "Pin=math.sqrt(3.)*VSL*abs(IS)*cos_fis*10**-6##MW\n",
      "print '%s %.2f' %(\"Power Input(MW) : \",Pin)#\n",
      "Eta=P*pf/(Pin*10**6)*100.##%\n",
      "print '%s %.2f' %(\"Transmission Efficiency(%) : \",Eta)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end Line voltage(kV) :  118.28\n",
        "Sending end current(A), magnitude is  62400.97  and angle in degree is  89.80\n",
        "Sending end power factor(lag) :  -0.01\n",
        "Power Input(MW) :  -134.12\n",
        "Transmission Efficiency(%) :  -29.82\n"
       ]
      }
     ],
     "prompt_number": 68
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E22 - Pg 153"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate \n",
      "import math\n",
      "import cmath\n",
      "import numpy\n",
      "from numpy import roots\n",
      "#Given data :\n",
      "f=50##Hz\n",
      "L=300##km\n",
      "r=0.15##ohm/km\n",
      "x=0.5##ohm/km\n",
      "y=3*10**-6##mho/km\n",
      "VRL=220*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "P=200*10**6##W\n",
      "pf=0.85##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "R=r*L##ohm\n",
      "X=x*L##ohm\n",
      "Y=y*L##mho\n",
      "Z=R+1j*X##ohm\n",
      "#part (i)\n",
      "A=1+1/2.*1j*Y*Z##parameter of 3-phase line\n",
      "D=A##parameter of 3-phase line\n",
      "B=Z##parameter of 3-phase line\n",
      "C=1j*Y*(1.+1./4.*1j*Y*Z)##parameter of 3-phase line\n",
      "print '%s %.4f %s %.2f' %(\"Parameter A, magnitude is \",abs(A),\" and angle in degree is \",cmath.phase(A)*180/math.pi)#\n",
      "print '%s %.1f %s %.1f' %(\"Parameter B, magnitude is \",abs(B),\" and angle in degree is \",cmath.phase(B)*180/math.pi)#\n",
      "print '%s %.2e %s %.2f' %(\"Parameter C, magnitude is \",abs(C),\" and angle in degree is \",cmath.phase(C)*180/math.pi)#\n",
      "print '%s %.2f %s %.2f' %(\"Parameter D, magnitude is \",abs(D),\" and angle in degree is \",cmath.phase(D)*180/math.pi)#\n",
      "#part (ii)\n",
      "p=([0.024525, 11.427, -2102])##from VS=A*VR+B*IR##Volt\n",
      "IR=roots(p)#\n",
      "IR=IR[1]##taking +ve value\n",
      "P=math.sqrt(3.)*VRL*IR*10**-6##MW\n",
      "print '%s %.1f' %(\"Power received in MW : \",P)#\n",
      "#/part (iii)\n",
      "P=200.*10.**6##W\n",
      "IR=P/math.sqrt(3.)/VRL/pf##A\n",
      "fi=math.acos(pf) *180./math.pi##degree\n",
      "IR=IR*math.cos(-fi*math.pi/180.) + 1j*math.sin(-fi*math.pi/180.)#\n",
      "VS=A*VR+B*IR##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end Line voltage(kV) : \",VSL/1000.)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Parameter A, magnitude is  0.9327  and angle in degree is  1.24\n",
        "Parameter B, magnitude is  156.6  and angle in degree is  73.3\n",
        "Parameter C, magnitude is  8.70e-04  and angle in degree is  90.60\n",
        "Parameter D, magnitude is  0.93  and angle in degree is  1.24\n",
        "Power received in MW :  53.8\n",
        "Sending end Line voltage(kV) :  283.60\n"
       ]
      }
     ],
     "prompt_number": 59
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E23 - Pg 154"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#Exa 5.23\n",
      "import math \n",
      "import cmath\n",
      "#Given data :\n",
      "A=0.936+1j*0.016##parameter of 3-phase line\n",
      "D=A##parameter of 3-phase line\n",
      "B=33.5+1j*138##parameter of 3-phase line\n",
      "C=(-0.9280+1j*901.223)*10**-6##parameter of 3-phase line\n",
      "VRL=200.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "P=40*10**6##W\n",
      "pf=0.86##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "IR=P/math.sqrt(3.)/VRL/pf##A\n",
      "fi=math.acos(pf) *180/math.pi##degree\n",
      "IR=IR*(math.cos(-fi*math.pi/180.) + 1j*math.sin(-fi*math.pi/180.))#\n",
      "VS=A*VR+B*IR##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end Line voltage(kV) : \",VSL/1000.)#\n",
      "IS=C*VR+D*IR##A\n",
      "print '%s %.1f %s %.2f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS)*180/math.pi)#\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)##degree\n",
      "print '%s %.4f' %(\"Sending end phase angle(degree): \",math.cos(fi_s))#\n",
      "Ps=math.sqrt(3.)*abs(VSL)*abs(IS)*math.cos(fi_s)*10**-6##MW\n",
      "print '%s %.3f' %(\"Sending end power(MW) : \",Ps)#\n",
      "Vreg=(VSL-VRL)*100./VRL##%\n",
      "print '%s %.2f' %(\"Voltage regulation in % : \",Vreg)#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end Line voltage(kV) :  211.98\n",
        "Sending end current(A), magnitude is  116.8  and angle in degree is  20.96\n",
        "Sending end phase angle(degree):  0.9716\n",
        "Sending end power(MW) :  41.665\n",
        "Voltage regulation in % :  5.99\n"
       ]
      }
     ],
     "prompt_number": 54
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E24 - Pg 155"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end Line voltage(kV)\n",
      "import cmath\n",
      "import math\n",
      "#Given data :\n",
      "A1=0.98*(math.cos(2.*math.pi/180.) + 1j*math.sin(2.*math.pi/180.))##parameter of 3-phase line\n",
      "D1=A1##parameter of 3-phase line\n",
      "B1=28.*(math.cos(69.*math.pi/180.) + 1j*math.sin(69.*math.pi/180.))##parameter of 3-phase line\n",
      "C1=0.0002*(math.cos(88.*math.pi/180.) + 1j*math.sin(88.*math.pi/180.))##parameter of 3-phase line\n",
      "A2=0.95*(math.cos(3.*math.pi/180.) + 1j*math.sin(3.*math.pi/180.))##parameter of 3-phase line\n",
      "D2=A2##parameter of 3-phase line\n",
      "B2=40.*(math.cos(85.*math.pi/180.) + 1j*math.sin(85.*math.pi/180.))##parameter of 3-phase line\n",
      "C2=0.0004*(math.cos(90.*math.pi/180.) + 1j*math.sin(90.*math.pi/180.))##parameter of 3-phase line\n",
      "VRL=110.*10**3##Volt\n",
      "VR=VRL/math.sqrt(3.)##Volt\n",
      "IR=200.##A\n",
      "pf=0.95##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "fi=math.cos(pf)##degree\n",
      "A=A1*A2+B1*C2##generalized parameter of 2 line\n",
      "B=A1*B2+B1*D2##generalized parameter of 2 line\n",
      "C=C1*A2+D1*C2##generalized parameter of 2 line\n",
      "D=C1*B2+D1*D2##generalized parameter of 2 line\n",
      "IR=IR*(math.cos(-fi*math.pi/180.) + 1j*math.sin(-fi*math.pi/180.))#\n",
      "VS=A*VR+B*IR##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "print '%s %.2f' %(\"Sending end Line voltage(kV) : \",VSL/1000)#\n",
      "IS=C*VR+D*IR##A\n",
      "print '%s %.2f %s %.2f' %(\"Sending end current(A), magnitude is \",abs(IS),\" and angle in degree is \",cmath.phase(IS)*180/math.pi)#\n",
      "#Answer for VSL is wrong in the book.\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Sending end Line voltage(kV) :  109.34\n",
        "Sending end current(A), magnitude is  190.09  and angle in degree is  15.72\n"
       ]
      }
     ],
     "prompt_number": 51
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example E25 - Pg 156"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate Sending end power factor(lagging)\n",
      "import cmath\n",
      "import math\n",
      "#Given data :\n",
      "A1=0.98*(math.cos(1.*math.pi/180.) + 1j*math.sin(1.*math.pi/180.))##parameter of 3-phase line\n",
      "D1=A1##parameter of 3-phase line\n",
      "B1=100*(math.cos(75.*math.pi/180.) + 1j*math.sin(75.*math.pi/180.))##parameter of 3-phase line\n",
      "C1=0.0005*(math.cos(90.*math.pi/180.) + 1j*math.sin(90.*math.pi/180.))##parameter of 3-phase line\n",
      "A2=0.98*(math.cos(1.*math.pi/180.) + 1j*math.sin(1.*math.pi/180.))##parameter of 3-phase line\n",
      "D2=A2##parameter of 3-phase line\n",
      "B2=100*(math.cos(75.*math.pi/180.) + 1j*math.sin(75.*math.pi/180.))##parameter of 3-phase line\n",
      "C2=0.0005*(math.cos(90.*math.pi/180.) + 1j*math.sin(90.*math.pi/180.))##parameter of 3-phase line\n",
      "P=100*10**6##W\n",
      "VRL=132*10**3##Volt\n",
      "VR=VRL/math.sqrt(3)##Volt\n",
      "pf=0.8##power factor\n",
      "cos_fi_r=pf#\n",
      "sin_fi_r=math.sqrt(1-cos_fi_r**2)#\n",
      "fi=math.acos(pf)##degree\n",
      "A=(A1*B2+A2*B1)/(B1+B2)##generalized parameter of 2 line\n",
      "B=B1*B2/(B1+B2)##generalized parameter of 2 line\n",
      "C=C1+C2-(A1-A2)*(D1-D2)/(B1+B2)##generalized parameter of 2 line\n",
      "D=(B1*D2+B2*D1)/(B1+B2)##generalized parameter of 2 line\n",
      "print '%s' %(\"Generalised constants ot two lines combined are : \")#\n",
      "print '%s %.2f %s %.f' %(\"Parameter A, magnitude is \",abs(A),\" and angle in degree is \",cmath.phase(A)*180/math.pi)#\n",
      "print '%s %.f %s %.2f' %(\"Parameter B, magnitude is \",abs(B),\" and angle in degree is \",cmath.phase(B)*180/math.pi)#\n",
      "print '%s %.3f %s %.2f' %(\"Parameter C, magnitude is \",abs(C),\" and angle in degree is \",cmath.phase(C)*180/math.pi)#\n",
      "print '%s %.2f %s %.2f' %(\"Parameter D, magnitude is \",abs(D),\" and angle in degree is \",cmath.phase(D)*180/math.pi)#\n",
      "IR=P/math.sqrt(3.)/VRL/pf##A\n",
      "IR=IR*(math.cos(-fi*math.pi/180.) + 1j*math.sin(-fi*math.pi/180.))#\n",
      "VS=A*VR+B*IR##Volt\n",
      "VSL=math.sqrt(3.)*abs(VS)##Volt\n",
      "IS=C*VR+D*IR##A\n",
      "fi_s=cmath.phase(VS)-cmath.phase(IS)#\n",
      "print '%s %.4f' %(\"Sending end power factor(lagging) : \",math.cos(fi_s))#\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Generalised constants ot two lines combined are : \n",
        "Parameter A, magnitude is  0.98  and angle in degree is  1\n",
        "Parameter B, magnitude is  50  and angle in degree is  75.00\n",
        "Parameter C, magnitude is  0.001  and angle in degree is  90.00\n",
        "Parameter D, magnitude is  0.98  and angle in degree is  1.00\n",
        "Sending end power factor(lagging) :  0.9843\n"
       ]
      }
     ],
     "prompt_number": 50
    }
   ],
   "metadata": {}
  }
 ]
}