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{
 "metadata": {
  "name": ""
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 2: Transformers"
     ]
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.1, Page number: 63"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "Pc=16                               #Core loss at Bmax=1.5 T\n",
      "VIrms=20                            #Voltamperess for the core\n",
      "Vrms=194                            #Rms induced voltage(V)\n",
      "\n",
      "\n",
      "#Calculation:\n",
      "pf=Pc/VIrms\n",
      "a=math.acos(pf)\n",
      "I=VIrms/Vrms\n",
      "Ic=I*pf\n",
      "Im=I*math.fabs(math.sin(a))\n",
      "\n",
      "#Results:\n",
      "print \"Power factor = \", round(pf,1),\"lagging\"\n",
      "print \"The core-loss current,Ic =\", round(Ic,3), \"A rms\"\n",
      "print \"The magnetising current,Im =\", round(Im,2),\"A rms\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Power factor =  0.8 lagging\n",
        "The core-loss current,Ic = 0.082 A rms\n",
        "The magnetising current,Im = 0.06 A rms\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.2, Page number: 67"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "\n",
      "#Variable declarations:\n",
      "k=5                                 #turns ratio,N1/N2\n",
      "Z2=1+4j                             #Impedance of secondary side(ohm)\n",
      "Vp=120                              #primary voltage(V)\n",
      "\n",
      "#Calculations:\n",
      "Z2p=k**2*(Z2)\n",
      "I=Vp/Z2p\n",
      "Is=k*I\n",
      "\n",
      "#Results:\n",
      "print \"Primary current:\",complex(round(I.real,2),round(I.imag,2)), \"A rms\"\n",
      "print \"Current in the short:\",round(Is.real,2)+1j*round(Is.imag,2),\"A\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Primary current: (0.28-1.13j) A rms\n",
        "Current in the short: (1.41-5.65j) A\n"
       ]
      }
     ],
     "prompt_number": 53
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.4, Page number: 74"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import cmath\n",
      "\n",
      "#Variable declaration:\n",
      "R1=0.72                                 #Resistance at high voltage side(ohm)\n",
      "R2=0.70                                 #Resistance at low voltage side(ohm)\n",
      "X1=0.92                                 #Reactance at high voltage side(ohm)\n",
      "X2=0.90                                 #Reactance at low voltage side(ohm)\n",
      "Zq=632+4370j                            #Impedance of exciting circuit(ohm)\n",
      "\n",
      "#Calculations:\n",
      "Req=R1+R2\n",
      "Xeq=X1+X2       \n",
      "Vcd=2400*Zq/(Zq+complex(R1,X1))\n",
      "V=complex(round(Vcd.real,2),round(Vcd.imag,3))\n",
      "\n",
      "#Results:\n",
      "print \"Req:\",Req,\"ohm\",\" and  Xeq:\",Xeq,\"ohm\"\n",
      "print \"Voltage at low voltage terminal:\",V,\"V\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Req: 1.42 ohm  and  Xeq: 1.82 ohm\n",
        "Voltage at low voltage terminal: (2399.45+0.316j) V\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.5, Page number: 76"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import math\n",
      "\n",
      "#Variable declaration:\n",
      "Zf=0.30+.160j                           #Impedance of feeder(ohm)\n",
      "Zeq=1.42+3.42j             #Equiv.impedance of transformer refd. to primary(ohm)\n",
      "k=2400/240                              #turns ratio\n",
      "P=50000                                 #power rating of the transformer(VA)\n",
      "Vs=2400                                 #sending end vltage of feeder(V)\n",
      "\n",
      "\n",
      "\n",
      "#Calculations:\n",
      "I=P/2400                                #Rated current(A)\n",
      "theta=math.acos(0.80)\n",
      "Zt=Zf+Zeq                      #combned impedance of feeder & transformer(ohm)\n",
      "R=Zt.real\n",
      "X=Zt.imag\n",
      "bc=I*X*math.cos(theta)-I*R*math.sin(theta)\n",
      "ab=I*R*math.cos(theta)+I*X*math.sin(theta)\n",
      "Ob=(Vs**2-bc**2)**0.5\n",
      "V2=Ob-ab\n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"The voltage at the secondary terminals:\",round(V2/10,0),\"V\\n\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The voltage at the secondary terminals: 233.0 V\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.6, Page number: 80"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import cmath\n",
      "import math\n",
      "\n",
      "#Variable declaration:\n",
      "#short ckt test readings:\n",
      "Vsc=48                          #voltage(V)\n",
      "Isc=20.8                        #current(A)\n",
      "Psc=617                         #power(W)\n",
      "    \n",
      "#Open ckt test readings:\n",
      "Vs=240                         #Voltage(V)\n",
      "I=5.41                          #current(A)\n",
      "P=186                           #power(W)\n",
      "V2ph=2400                        #voltage at full load at high voltage side(V)\n",
      "pf=0.8                          #lagging power factor at full load\n",
      "\n",
      "\n",
      "\n",
      "#Calculations:\n",
      "theta=math.acos(pf)\n",
      "Zeqh=Vsc/Isc                    #subscript h refers to high voltage side\n",
      "Reqh=Psc/Isc**2\n",
      "Xeqh=math.sqrt(Zeqh**2-Reqh**2)\n",
      "Ih=50000/V2ph\n",
      "Pout=50000*pf\n",
      "Pwind=Ih**2*Reqh\n",
      "Ptloss=P+Pwind\n",
      "e=(1-Ptloss/(Ptloss+Pout))*100\n",
      "Iph=(50000/2400)*complex(math.cos(theta),math.sin(-theta))\n",
      "V1ph=V2ph+Iph*complex(Reqh,Xeqh)\n",
      "r=(round(abs(V1ph),2)-2400)*100/V2ph\n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"The efficiency of the transformer:\",round(e,0),\"%\"\n",
      "print \"Volatge Regulation:\",round(r,2),\"%\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The efficiency of the transformer: 98.0 %\n",
        "Volatge Regulation: 1.94 %\n"
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.7, Page number: 82"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "\n",
      "#Varaible declaration:\n",
      "Vx=2400                                 #Voltage at low voltage side(V)\n",
      "Vbc=2400                                 #Voltage across branch bc(V)\n",
      "Vab=240                                #Voltage induced in winding ab(V)\n",
      "Pl=803                                  #transformer losses(W)\n",
      "pf=0.8                                  #Power factor of the transformer\n",
      "\n",
      "#Calculations:\n",
      "Vh=Vab+Vbc\n",
      "Ih=50000/Vab\n",
      "KVA=Vh*Ih/1000                          #Kva rating\n",
      "P=pf*550000\n",
      "e=(1-Pl/(P+Pl))*100\n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"Voltage ratings, Vh:\",Vh,\"V  \", \"&  Vx:\",Vx,\"V\"\n",
      "print \"KVA rating as an autotransformer:\",KVA,\"KVA\"\n",
      "print \"full-load efficiency:\", round(e,2),\"%\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Voltage ratings, Vh: 2640 V   &  Vx: 2400 V\n",
        "KVA rating as an autotransformer: 550.0 KVA\n",
        "full-load efficiency: 99.82 %\n"
       ]
      }
     ],
     "prompt_number": 24
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.8, Page number: 87"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import math\n",
      "\n",
      "#Variable declaration:\n",
      "Vl1=4160                      #line-to-line voltage at feeder's sending end(V)\n",
      "Zf=0.30+.160j                           #Impedance of feeder(ohm)\n",
      "Zeq=1.42+3.42j             #Equiv.impedance of transformer refd. to primary(ohm)\n",
      "k=2400/240                              #turns ratio\n",
      "P=50000                                 #power rating of the transformer(VA)\n",
      "Vs=2400                                 #sending end vltage of feeder(V)\n",
      "\n",
      "\n",
      "\n",
      "#Calculation:\n",
      "#this problem can be treated on a single phase basis,\n",
      "#and whole problem is similar to Ex 2.5.\n",
      "\n",
      "I=P/2400                                #Rated current(A)\n",
      "theta=math.acos(0.80)\n",
      "Zt=Zf+Zeq                      #combned impedance of feeder & transformer(ohm)\n",
      "R=Zt.real\n",
      "X=Zt.imag\n",
      "bc=I*X*math.cos(theta)-I*R*math.sin(theta)\n",
      "ab=I*R*math.cos(theta)+I*X*math.sin(theta)\n",
      "Ob=(Vs**2-bc**2)**0.5\n",
      "V2=Ob-ab\n",
      "Vload=V2/k\n",
      "\n",
      "#Results:\n",
      "print \"The line to line voltage:\",round(Vload,0),\"V line-to-line\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The line to line voltage: 233.0 V line-to-line\n"
       ]
      }
     ],
     "prompt_number": 25
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.9, Page number: 89"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import math\n",
      "import cmath\n",
      "\n",
      "#Variable decclaration:\n",
      "#All resistances, reactances, & impedances are on per phase basis\n",
      "Req=1.42       #Series resist. of del-del transformer referred to 2400v side(ohm)\n",
      "Xeq=1.82       #Series react. of del-del transformer referred to 2400v side(ohm)\n",
      "Zs=0.17+0.92j                   #Equiv impedance of sending end transformer(ohm)\n",
      "Xf=0.8j                          #Reactance of the feeder(ohm)\n",
      "Vf=2400                         #Voltage of the feeder(V)\n",
      "k=10                            #turns ratio(Vp/Vs)\n",
      "\n",
      "\n",
      "#Calculations:\n",
      "Zt=(complex(Req,Xeq)/3)+Zs+Xf\n",
      "Ztot=complex(round(Zt.real,2),round(Zt.imag,2))\n",
      "If=math.floor(Vf/(math.sqrt(3))/round(abs(Ztot),2))\n",
      "I1=If/math.sqrt(3)\n",
      "I2=I1*k\n",
      "Ic=I2*math.sqrt(3)\n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"Short circuit current in the 2400 feeder, per phase wires:\",round(Ic,1),\"A\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Short circuit current in the 2400 feeder, per phase wires: 5720.0 A\n"
       ]
      }
     ],
     "prompt_number": 8
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.10, Page number: 92"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import cmath\n",
      "from math import *\n",
      "\n",
      "#Variable declaration:\n",
      "X1=143                             #Reactance of primary(ohm)\n",
      "X21=164                           #Reactance of secondary ref. to primary(ohm)\n",
      "Xm=163*10**3                           #Reactance of magnetising ckt(ohm)\n",
      "R1=128                             #Resistance of primary(ohm)\n",
      "R21=141                           #Resistane of secondary ref. to primary(ohm)\n",
      "k=20                              #turns ratio(2400/120)\n",
      "V1=2400                             #primary voltage(V)\n",
      "\n",
      "\n",
      "\n",
      "#Calculations:\n",
      "V2=(V1/k)*complex(0,Xm)/complex(R1,X1+Xm)\n",
      "mag=abs(V2)\n",
      "ph=degrees(cmath.phase(V2))\n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"Magnitude of V2:\",round(mag,2),\"V\"\n",
      "print \"Phase of V2:\",round(ph,3),\"degrees\"\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Magnitude of V2: 119.89 V\n",
        "Phase of V2: 0.045 degrees\n"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.11, Page number: 94"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import cmath\n",
      "\n",
      "\n",
      "#variable declaration:\n",
      "X1=44.8*10**-6                  #Reactance of the primary(ohm)\n",
      "R1=10.3*10**-6                  #Resistance of the primary(ohm)\n",
      "X21=54.3*10**-6          #Reactance of the secondary refd. to primary(ohm)\n",
      "R21=9.6*10**-6                  #Resistance of secondary ref. to primary(ohm)\n",
      "Xm=17.7*10**-3                  #Reactance of the magnetising ckt(ohm)\n",
      "k=5/800                         #turms ratio(I2/I1)\n",
      "Zl=2.5+0j                       #Impedance ofthe load(ohm)\n",
      "I1=800                          #primary current(A)\n",
      "\n",
      "#Calculations:\n",
      "Zp=k**2*Zl\n",
      "I2=I1*k*Xm*1j/(Zp+R21+(X21+Xm)*1j)\n",
      "phase=cmath.phase(I2)\n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"Magnitude of current:\",round(abs(I2),2),\"A\"\n",
      "print \"Phase of the current:\",round(math.degrees(phase),3),\"degrees\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Magnitude of current: 4.98 A\n",
        "Phase of the current: 0.346 degrees\n"
       ]
      }
     ],
     "prompt_number": 11
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.12, Page number: 97"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import math\n",
      "\n",
      "#Variable declaration:\n",
      "XL=0.040                                #Reactance at l.v side(ohm)\n",
      "XH=3.75                                 #Reactance at h.v side(ohm)\n",
      "Xm=114                                  #Magnetising reactance(ohm)\n",
      "RL=0.76*10**-3                          #Resistance at l.v.side(ohm)\n",
      "RH=0.085                                #Resistance at l.v.side(ohm)\n",
      "VA_base=100*10**6                       #base VA\n",
      "V_base=7.97*10**3                       #base voltage(V)\n",
      "\n",
      "\n",
      "\n",
      "#Calculations:\n",
      "#for l.v side\n",
      "VA_base=100*10**6                       #base VA\n",
      "V_base=7.97*10**3                       #base voltage(V)\n",
      "Rbase1=Xbase1=V_base**2/VA_base\n",
      "\n",
      "#for h.v side:\n",
      "VA_base=100*10**6                       #base VA\n",
      "V_base=79.7*10**3                       #base voltage(V)\n",
      "Rbase2=Xbase2=V_base**2/VA_base\n",
      "\n",
      "XL_pu=XL/Xbase1\n",
      "XH_pu=XH/Xbase2\n",
      "Xm_pu=Xm/Xbase1\n",
      "RL_pu=RL/Rbase1\n",
      "RH_pu=RH/Rbase2\n",
      "K_pu=1                                  #per unit utrns ratio\n",
      "\n",
      "#Results:\n",
      "print \"The per unit parameters are:\"\n",
      "print \"XL_pu =\",round(XL_pu,3),\"p.u\"\n",
      "print \"XH_pu =\",round(XH_pu,4),\"p.u\"\n",
      "print \"Xm_pu =\",math.ceil(Xm_pu),\"p.u\"\n",
      "print \"RL_pu =\",round(RL_pu,4),\"p.u\"\n",
      "print \"XL_pu =\",round(RH_pu,4),\"p.u\"\n",
      "print \"Turns ratio =\",K_pu,\"p.u\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The per unit parameters are:\n",
        "XL_pu = 0.063 p.u\n",
        "XH_pu = 0.059 p.u\n",
        "Xm_pu = 180.0 p.u\n",
        "RL_pu = 0.0012 p.u\n",
        "XL_pu = 0.0013 p.u\n",
        "Turns ratio = 1 p.u\n"
       ]
      }
     ],
     "prompt_number": 59
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.13, Page number: 98"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "import cmath\n",
      "\n",
      "\n",
      "#Variable declaration:\n",
      "Ic=5.41                             #Exciting current ref. to low volt. side(A)\n",
      "k=10                                #turns ratio(N1/N2=2400/240)\n",
      "Vbh=2400                            #base voltage at primary side(V)\n",
      "Vbl=240                             #base voltage at secondary side(V)\n",
      "Ibh=20.8                            #base current at primary side(A)\n",
      "Ibl=208                             #base current at secondary side(A)\n",
      "Z=1.42+1.82j                    #Equiv.impedance ref.to high voltage side(ohm)\n",
      "\n",
      "\n",
      "\n",
      "#Calculations:\n",
      "Zbh=Vbh/Ibh\n",
      "Zbl=Vbl/Ibl\n",
      "Icl=Ic/Ibl\n",
      "Ich=Ic/(Ibh*k)\n",
      "Zl=Z/(k**2*Zbl)\n",
      "Zh=Z/Zbh\n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"Per unit exciting current on low volt. sides:\",round(Icl,3,),\"A\"  \n",
      "print \"Per unit exciting current on high volt. sides:\",round(Ich,3),\"A\"\n",
      "print \"per unit equiv.impedance at low volt. sides:\",round(Zl.real,4)+round(Zl.imag,4)*1j,\"ohm\"\n",
      "print \"per unit equiv.impedance at high voltage sides:\",round(Zh.real,4)+round(Zh.imag,4)*1j,\"ohm\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Per unit exciting current on low volt. sides: 0.026 A\n",
        "Per unit exciting current on high volt. sides: 0.026 A\n",
        "per unit equiv.impedance at low volt. sides: (0.0123+0.0158j) ohm\n",
        "per unit equiv.impedance at high voltage sides: (0.0123+0.0158j) ohm\n"
       ]
      }
     ],
     "prompt_number": 12
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.14, Page number: 100"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "from math import *\n",
      "\n",
      "\n",
      "#Variable declaration:\n",
      "Vb=24000               #Base voltage of secondary of sending end transformer(V)    \n",
      "Z=0.17+0.92j      #Impedance of sending end transformer ref. to 2400V side(ohm)\n",
      "P=150                       #Power rating of the transformer(KVA)\n",
      "V=2400                      #Primary voltage of sending end transformer(v)\n",
      "Ztot=0.64+2.33j                 #Total series impedance(ohm)\n",
      "\n",
      "#Calculations:\n",
      "Zb=V**2/(P*10**3)\n",
      "Ztotb=Ztot/Zb\n",
      "Vsb=1                           #Vs in terms of per unit values\n",
      "Isc=Vsb/abs(Ztotb)                   #Short current in per unit values(A)\n",
      "Ib1=P*10**3/(sqrt(3)*2400)       #base current of the feeder at 2400V side(A)\n",
      "If=Ib1*Isc\n",
      "Ib2=P*10**3/(sqrt(3)*240)\n",
      "Iscs=Isc*Ib2                     #short ckt current at 2400V afeeder side (A)\n",
      "\n",
      "#Results:\n",
      "print \"Short circuit current in 2400 feeder:\",round(Iscs/10**3,2),\"KA\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Short circuit current in 2400 feeder: 5.73 KA\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 2.15, Page number: 102"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from __future__ import division\n",
      "\n",
      "#Variable declaration:\n",
      "P=250*10**3                            #power rating of transformer(KVA)\n",
      "Vp=2400                             #primary volatge(V)\n",
      "Vs=460                              #secondary voltage(V)\n",
      "Pb=100*10**3                           #new base power of transformer(KVA)\n",
      "Vb=460                              #new base voltage(V)\n",
      "Z=0.026+0.12j                       #series impedance on its own base(ohm)\n",
      "Vl=438                              #load voltage(V)\n",
      "Pl=95*10**3                         #power drawn by the load(kW)\n",
      "\n",
      "#Calculations:\n",
      "Zbo=Vs**2/P                        #base impedance for the transformer(ohm)\n",
      "Zbn=Vb**2/Pb            #base impedance for the transformer at 100KVA base(ohm)\n",
      "Zpn=Z*Zbo/Zbn                      #base impedance at 100KVA base(ohm)\n",
      "Vpl=Vl/Vb                           #per unit load voltage(V)\n",
      "Ppl=Pl/Pb                          #per unit load power\n",
      "Ipl=Ppl/Vpl                             #per unit load current(A)\n",
      "Vpp=Vpl+Ipl*Zpn                     #high side voltage of the transformer(V) \n",
      "\n",
      "\n",
      "#Results:\n",
      "print \"The high side voltage:\",round(abs(Vpp*Vp),0),\"V\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The high side voltage: 2313.0 V\n"
       ]
      }
     ],
     "prompt_number": 14
    }
   ],
   "metadata": {}
  }
 ]
}