path: root/sample_notebooks/SaurabhBarot/ch2.ipynb

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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 2 : MAGNETIC CIRCUITS"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.1  Page No : 89"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "\n",
      "#INPUT DATA\n",
      "N = 2000.;\t\t\t#no of turns\n",
      "I = 10.;\t\t\t#current in A\n",
      "Rm = 25.;\t\t\t#mean radius in cm\n",
      "d = 6.;\t\t\t#diameter of each turn in cm\n",
      "\n",
      "#CALCULATIONS \n",
      "MMF = N*I;\t\t\t#magneto motive force in A\n",
      "l = 2*math.pi*(Rm/100);\t\t\t#circumference of coli in m\n",
      "u = (4*math.pi*10**-7);\t\t\t#permeability (U = Ur*U0)\n",
      "a = (math.pi*d*d*10**-4)/4;\n",
      "reluctance = (l/(a*u));\t\t\t#reluctance in At/Wb\n",
      "flux = (MMF)/(reluctance);\t\t\t#flux in Wb\n",
      "fluxdensity = (flux/a);\t\t\t#flux density in Wb/m**2 or tesla\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus MMF, flux, flux density  are %d A, %g Wb , %g Wb/m**2 or Tesla respectively \"%(MMF,flux,fluxdensity);\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus MMF, flux, flux density  are 20000 A, 4.52389e-05 Wb , 0.016 Wb/m**2 or Tesla respectively \n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.2  Page No : 90"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "#Chapter-2, Example 2.2, Page 90\n",
      "\n",
      "#INPUT DATA\n",
      "phi = 5*10**-2;\t\t\t#flux in wb\n",
      "a = 0.2;\t\t\t#area of cross-section in m**2\n",
      "lg = 1.2*10**-2;\t\t\t#length of air gap in m\n",
      "ur = 1;\t\t\t#permeability\n",
      "u = ur*4*math.pi*10**-7;\t\t\t#permeability\n",
      "\n",
      "#CALCULATIONS \n",
      "B = (phi/a);\t\t\t#flux density in wb/sq.m\n",
      "H = (B/(4*math.pi*10**-7*ur));\t\t\t#magnetic flux density in A/m\n",
      "S = lg/(a*u);\t\t\t#reluctance of air gap in A/wb\n",
      "permeance = 1/S;\t\t\t#permenace in A/wb\n",
      "mmf_in_airgap = phi*S;\t\t\t#mmf in A\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus B, H,S, permeance, MMF in air gap  are %1.2f Wb/sq.m, %g A/m ,%f A/wb ,\\\n",
      "%g Wb/A %d A  respectively \"%(B,H,S,permeance,mmf_in_airgap);\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus B, H,S, permeance, MMF in air gap  are 0.25 Wb/sq.m, 198944 A/m ,47746.482928 A/wb ,2.0944e-05 Wb/A 2387 A  respectively \n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.3  Page No : 90"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "\n",
      "#INPUT DATA\n",
      "phi = 0.1*10**-3;\t\t\t#flux in wb\n",
      "a = 1.7*10**-4;\t\t\t#area of cross-section in m**2\n",
      "lg = 0.5*10**-3;\t\t\t#length of air gap in m\n",
      "Rm = 15./2;\t\t\t#radius of ring in cm\n",
      "u0 = 4*math.pi*10**-7;\t\t\t#permeability in free space in henry/m\n",
      "N = 1500.;\t\t\t#no of turns of ring\n",
      "\n",
      "#CALCULATIONS \n",
      "B = (phi/a);\t\t\t#flux density in wb/sq.m\n",
      "H = (B/(4*math.pi*10**-7));\t\t\t#magnetic flux density in A/m\n",
      "ampere_turns_provided_fo = H*lg;\n",
      "total_ampere_turns_provi = N*1;\n",
      "Available_for_iron_path = N-(H*lg);\n",
      "length_of_iron_path = (2*Rm*math.pi*10**-2)-(lg);\t\t\t#length of iron path in m\n",
      "H_for_iron_path = ((N-(H*lg)))/(length_of_iron_path);\n",
      "ur = (B/(u0*H_for_iron_path));\t\t\t#relative permeability of iron\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus relative permeability of iron is %d\"%(ur);\n",
      "\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus relative permeability of iron is 174\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4  Page No : 91"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "\n",
      "#INPUT DATA\n",
      "li = 0.5;\t\t\t#iron path length in m\n",
      "lg = 10.**-3;\t\t\t#length of air gap in m\n",
      "phi = 0.9*10**-3;\t\t\t#flux in wb\n",
      "a = 6.66*10**-4;\t\t\t#area of cross-section of iron in m**2\n",
      "N = 400.;\t\t\t#no of turns \n",
      "\n",
      "#CALCULATIONS \n",
      "B = (phi/a);\t\t\t#flux density in wb/sq.m\n",
      "Hg = (B/(4*math.pi*10**-7));\t\t\t#magnetic flux density in A/m\n",
      "AT_required = Hg*lg;\t\t\t#AT required for air path\n",
      "Hi = 1000;\t\t\t#magnetic flux density in A/m\n",
      "AT_required_for_iron_pat = Hi*li;\n",
      "total_AT_required = (Hg*lg)+(Hi*li);\n",
      "I = ((Hg*lg)+(Hi*li))/(N);\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus exciting current required is %1.2f A\"%(I);\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus exciting current required is 3.94 A\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.5  Page No : 92"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "#Chapter-2, Example 2.5, Page 92\n",
      "\n",
      "#INPUT DATA\n",
      "r = 0.01;\t\t\t#radius in m\n",
      "lg = 10.**-3;\t\t\t#length of air gap in m\n",
      "Rm = (30./2)*10**-2;\t\t\t#mean radius in m\n",
      "ur = 800.;\t\t\t#relative permeability of iron\n",
      "ur2 = 1.;\t\t\t#relative permeability of air gap\n",
      "N = 250.;\t\t\t#no of turns\n",
      "phi = 20000.*10**-8;\t\t\t#flux in Wb\n",
      "u0 = 4*math.pi*10**-7;\t\t\t#permeability in free space \n",
      "a = math.pi*(r)**2;\t\t\t#area of cross-section in m\n",
      "leakage_factor = 1.1\n",
      "\n",
      "#CALCULATIONS \n",
      "reluctance_of_air_gap = (lg/(u0*ur2*a));\t\t\t#reluctance of air gap in A/wb\n",
      "li = (math.pi*(2*r)-(lg));\t\t\t#length of iron path in m\n",
      "reluctance_of_iron_path = ((math.pi*0.3)-(lg))/(4*math.pi*10**-7*800*a);\t\t\t#in A/wb\n",
      "total_reluctance = reluctance_of_air_gap+reluctance_of_iron_path;\t\t\t#in A/wb\n",
      "MMF = phi*total_reluctance;\t\t\t#in Ampere turns\n",
      "current_required = (MMF)/(N);\t\t\t#in A\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus current required is %1.2f A \"%(current_required);\n",
      "#Including leakage\n",
      "\n",
      "#CALCULATIONS\n",
      "MMF_of_airgap = phi*reluctance_of_air_gap;\t\t\t#in A/wb\n",
      "Total_flux_in_ironpath = leakage_factor*phi;\t\t\t#in Wb\n",
      "MMF_of_ironpath = Total_flux_in_ironpath*reluctance_of_iron_path;\t\t\t#in A\n",
      "Total_MMF = MMF_of_ironpath+MMF_of_airgap;\t\t\t#in A/wb\n",
      "current_required2 = Total_MMF/(N);\t\t\t#in A\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus current required is %1.3f A\"%(current_required2);\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus current required is 4.41 A \n",
        "Thus current required is 4.650 A\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.6  Page No : 93"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "\n",
      "#INPUT DATA\n",
      "l1 = 0.1;\t\t\t#length in m\n",
      "l2 = 0.18;\t\t\t#length in m\n",
      "l3 = 0.18;\t\t\t#length in m\n",
      "lg = 1.*10**-3;\t\t\t#airgap length in mm\n",
      "a1 = 6.25*10**-4;\t\t\t#area in m**2\n",
      "a2 = 3.*10**-4;\t\t\t#area in m**2\n",
      "ur = 800.;\t\t\t#relative permeability of iron path\n",
      "ur2 = 1.;\t\t\t#relative permeability in free space\n",
      "u0 = 4*math.pi*10**-7\n",
      "N = 600.;\n",
      "phi = 10.**-4;\t\t\t#airgap flux in Wb\n",
      "\n",
      "#CALCULATIONS \n",
      "#for the airgap\n",
      "Bg = (phi/(a1));\t\t\t#fluxdensity in Tesla\n",
      "Hg = (Bg/(u0*ur2));\t\t\t#magnetimath.sing force in A/m\n",
      "MMF1 = Hg*lg;\t\t\t#in A\n",
      "#for path I1\n",
      "B1 = 0.16;\t\t\t# flux density in tesla\n",
      "H1 = (B1/(ur*u0));\t\t\t#magnetimath.sing force in A/m\n",
      "MMF2 = H1*l1;\t\t\t#in A\n",
      "#math.since paths l2 and l3 are similar,the total flux divide equally between these two paths.Since these paths are in parallel,consider only one of them\n",
      "#for path l2\n",
      "flux = 50*10**-6;\t\t\t#flux in wb\n",
      "B2 = (flux/a2);\t\t\t#fluxdensity in tesla\n",
      "H2 = (B2/(ur*u0));\t\t\t#magnetimath.sing force in A/m\n",
      "MMF3 = H2*l2;\t\t\t#in A\n",
      "totalmmf = MMF1+MMF2+MMF3;\t\t\t#in A\n",
      "I = (totalmmf/N);\t\t\t#current required in A\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus current required is %1.3f A\"%(I);\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus current required is 0.288 A\n"
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.7  Page No : 95"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "#Chapter-2, Example 2.7, Page 95\n",
      "\n",
      "#INPUT DATA\n",
      "Dm = 0.1\t\t\t#diameter in m\n",
      "a = 10.**-3;\t\t\t#area of cross-section im m**2\n",
      "N = 150.;\t\t\t#no of turns\n",
      "ur = 800.;\t\t\t#permeability of iron ring\n",
      "B = 0.1;\t\t\t#in Wb/m**2\n",
      "u0 = 4*math.pi*10**-7;\t\t\t#permeability of free space\n",
      "\n",
      "#CALCULATIONS \n",
      "S = (math.pi*Dm)/(a*ur*u0);\t\t\t#reluctance\n",
      "I = (B*a*S)/(N);\t\t\t#current in A\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus current is %f A\"%(I);"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus current is 0.208333 A\n"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.8  Page No : 95"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "\n",
      "#INPUT DATA\n",
      "l = 0.3;\t\t\t#length in m\n",
      "d = 1.5*10**-2;\t\t\t#diameter in m\n",
      "N = 900;\t\t\t#no of turns\n",
      "ur = 1;\t\t\t#relative permeability in free space\n",
      "u0 = 4*math.pi*10**-7;\t\t\t#permeability in free space\n",
      "I = 5;\t\t\t#current in A\n",
      "\n",
      "#CALCULATIONS \n",
      "a = (math.pi*(d)**2/4);\t\t\t#in m**2\n",
      "S = (l)/(a*ur*u0);\t\t\t#reluctance\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus reluctance is %f A/wb\"%(S);\n",
      "\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus reluctance is 1350949115.231170 A/wb\n"
       ]
      }
     ],
     "prompt_number": 8
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.9  Page No : 95"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "\n",
      "#INPUT DATA\n",
      "lg = 10**-3;\t\t\t#length of air gap in m\n",
      "B = 0.9;\t\t\t#flux density in wb/m**2\n",
      "li = 0.3;\t\t\t#length of ironpath in m\n",
      "Hi = 800;\t\t\t#magnetic flux density in AT/m\n",
      "u0 = 4*math.pi*10**-7;\t\t\t#permeabilty in free space\n",
      "\n",
      "#CALCULATIONS \n",
      "#for iron path\n",
      "MMF_required1 = Hi*li;\t\t\t#magnetic motive force in AT\n",
      "#for air gap\n",
      "MMF_required2 = (B/u0)*lg;\t\t\t#magnetic motive force in AT\n",
      "Totalmmf = MMF_required1+MMF_required2\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus total MMF required is %d AT\"%(Totalmmf);\n",
      "\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus total MMF required is 956 AT\n"
       ]
      }
     ],
     "prompt_number": 9
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.10  Page No : 96"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math \n",
      "\n",
      "#INPUT DATA\n",
      "li = 0.5;\t\t\t#length of iron ring mean length in m\n",
      "N = 220;\t\t\t#no of turns\n",
      "I = 1.2;\t\t\t#current in A\n",
      "lg = 1.2*10**-3;\t\t\t#length of airgap in m\n",
      "ur = 350;\t\t\t#relative permeability of iron\n",
      "u0 = 4*math.pi*10**-7;\t\t\t#permeability in free space\n",
      "\n",
      "#CALCULATIONS \n",
      "MMF_produced = N*I;\n",
      "Si = li/(u0*ur);\t\t\t#reluctance of iron path\n",
      "Sg = lg/(u0);\t\t\t#reluctance of air gap\n",
      "S = Si+Sg;\t\t\t#total reluctance \n",
      "Flux_density = (MMF_produced)/(S);\n",
      "\n",
      "#OUTPUT\n",
      "print \"Thus fluxdensity is %1.3f Wb/m**2\"%(Flux_density);\n",
      "\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thus fluxdensity is 0.126 Wb/m**2\n"
       ]
      }
     ],
     "prompt_number": 10
    }
   ],
   "metadata": {}
  }
 ]
}