{ "metadata": { "name": "", "signature": "sha256:46dd88e506b63134e24582a78d5a791547c8824340e8bb4b0b9ee7239c438783" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "

Chapter 43: Magnetically coupled circuits

" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 1, page no. 842

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "Na = 1200; \n", "Nb = 1000;\n", "Ia = 0.8;# in amperes\n", "Phia = 100E-6;# in Wb\n", "xb = 0.75;\n", "\n", " #calculation:\n", " #self inductance of coil A\n", "La = Na*Phia/Ia\n", " #mutual inductance, M\n", "Phib = xb*Phia\n", "M = Nb*Phib/Ia\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n self inductance of coil A is \",La,\" H\"\n", "print \"\\n mutual inductance, M is \",M,\"H\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " self inductance of coil A is 0.15 H\n", "\n", " mutual inductance, M is 0.09375 H" ] } ], "prompt_number": 1 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 2, page no. 843

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "M = 600E-3;# in Henry\n", "Ia = 5;# in amperes\n", "dt = 0.2;# in secs\n", "\n", " #calculation:\n", " #change of current\n", "dIa = 2*Ia \n", "dIadt = dIa/dt\n", " #secondary induced e.m.f., E2\n", "E2 = -1*M*dIadt\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n secondary induced e.m.f., E2 is \",E2,\" V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " secondary induced e.m.f., E2 is -30.0 V" ] } ], "prompt_number": 2 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 3, page no. 844

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "La = 250E-3;# in Henry\n", "Lb = 400E-3;# in Henry\n", "M = 80E-3;# in Henry\n", "\n", " #calculation:\n", " #coupling coefficient,\n", "k = M/(La*Lb)**0.5\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n coupling coefficient, is \",round(k,3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " coupling coefficient, is 0.253" ] } ], "prompt_number": 3 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 4, page no. 845

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "Lx = 80E-3;# in Henry\n", "Ly = 60E-3;# in Henry\n", "Nx = 200;# turns\n", "Ny = 100;# turns\n", "Ix = 4;# in Amperes\n", "Phiy = 0.005;# in Wb\n", "\n", "#calculation:\n", " #mutual inductance, M\n", "M = Ny*Phiy/(2*Ix)\n", " #coupling coefficient,\n", "k = M/(Lx*Ly)**0.5\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n mutual inductance, M is \",M*1E3,\"mH\"\n", "print \"\\n coupling coefficient, is \",round(k,3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " mutual inductance, M is 62.5 mH\n", "\n", " coupling coefficient, is 0.902" ] } ], "prompt_number": 4 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 5, page no. 846

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "La = 40E-3;# in Henry\n", "Lb = 10E-3;# in Henry\n", "L = 60E-3;# in Henry\n", "\n", " #calculation:\n", " #mutual inductance, M\n", "M = (L - La - Lb)/2\n", " #coupling coefficient,\n", "k = M/(La*Lb)**0.5\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n mutual inductance, M is \",M*1E3,\"mH\"\n", "print \"\\n coupling coefficient, is \",k" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " mutual inductance, M is 5.0 mH\n", "\n", " coupling coefficient, is 0.25" ] } ], "prompt_number": 5 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 6, page no. 847

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "V = 240;# in Volts\n", "Ra = 5;# in Ohm\n", "La = 1;# in Henry\n", "Rb = 10;# in Ohm\n", "Lb = 5;# in Henry\n", "I = 8;# in amperes\n", "dIdt = 15;# in A/sec\n", "\n", " #calculation:\n", " #Kirchhoff\u2019s voltage law\n", "L = (V - I*(Ra + Rb))/dIdt\n", " #mutual inductance, M\n", "M = (L - La - Lb)/2\n", " #coupling coefficient,\n", "k = M/(La*Lb)**0.5\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n mutual inductance, M is \",M,\"H\"\n", "print \"\\n coupling coefficient, is \",round(k,3)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " mutual inductance, M is 1.0 H\n", "\n", " coupling coefficient, is 0.447" ] } ], "prompt_number": 6 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 7, page no. 848

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "k = 0.7;# coefficient of coupling\n", "L1 = 15E-3;# in Henry\n", "L2 = 10E-3;# in Henry\n", "\n", "#calculation:\n", " #L1 = La + Lb + 2*k*(La*Lb)**0.5\n", " #L2 = La + Lb - 2*k*(La*Lb)**0.5\n", " #self inductance of coils\n", "a = ((L1 - (L1 + L2)/2)/(2*k))**2\n", "La1 =((L1 + L2)/2 + (((L1 + L2)/2)**2 - 4*a)**0.5)/2\n", "La2 =((L1 + L2)/2 - (((L1 + L2)/2)**2 - 4*a)**0.5)/2\n", "Lb1 = (L1 + L2)/2 - La1\n", "Lb2 = (L1 + L2)/2 - La2\n", " #mutual inductance, M\n", "M = (L1 - L2)/4\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\nself inductance of coils are \",round(La1*1E3,2),\"mH and \",round( Lb1*1E3,2),\"mH\"\n", "print \"\\n mutual inductance, M is \",round(M*1E3,2),\"mH\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", "self inductance of coils are 12.24 mH and 0.26 mH\n", "\n", " mutual inductance, M is 1.25 mH\n" ] } ], "prompt_number": 1 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 8, page no. 850

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 8;# in Volts\n", "thetae1 = 0;# in degrees\n", "w = 2500;# in rad/sec\n", "R = 15;# in ohm\n", "L = 5E-3;# in Henry\n", "M = 0.1E-3;# in Henry\n", "\n", " #calculation:\n", " #voltage\n", "E1 = E1*math.cos(thetae1*math.pi/180) + 1j*E1*math.sin(thetae1*math.pi/180)\n", " #Impedance of primary\n", "Z1 = R + 1j*w*L\n", " #Primary current I1\n", "I1 = E1/Z1\n", " #E2\n", "E2 = 1j*w*M*I1\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\nE2 is \",round(abs(E2),3),\"/_\",round(cmath.phase(complex(E2.real,E2.imag))*180/math.pi,2),\"deg V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", "E2 is 0.102 /_ 50.19 deg V" ] } ], "prompt_number": 8 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 9, page no. 850

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "Lx = 20E-3;# in Henry\n", "Ly = 80E-3;# in Henry\n", "k = 0.75;# coupling coeff.\n", "Ex = 5;# in Volts\n", "\n", " #calculation:\n", " #mutual inductance\n", "M = k*(Lx*Ly)**0.5\n", " #magnitude of the open circuit e.m.f. induced\n", "Ey = M*Ex/Lx\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n mutual inductance is \",M,\" H\"\n", "print \"\\n magnitude of the open circuit e.m.f. induced is \",Ey,\" V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " mutual inductance is 0.03 H\n", "\n", " magnitude of the open circuit e.m.f. induced is 7.5 V" ] } ], "prompt_number": 9 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 10, page no. 852

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 2;# in Volts\n", "thetae1 = 0;# in degrees\n", "f = 1000/math.pi;# in Hz\n", "R1 = 4;# in ohm\n", "R2 = 16;# in ohm\n", "R3 = 16;# in ohm\n", "R4 = 50;# in ohm\n", "L = 10E-3;# in Henry\n", "M = 2E-3;# in Henry\n", "\n", "#calculation:\n", "w = 2*math.pi*f\n", " #R1e is the real part of Z1e\n", "R1e = R1 + R2 + ((R3 + R4)*(M**2)*(w**2))/((R3 + R4)**2 + (w*L)**2)\n", " #X1e is the imaginary part of Z1e\n", "X1e = w*L - (L*(M**2)*(w**3))/((R3 + R4)**2 + (w*L)**2)\n", "Z1e = R1e + 1j*X1e\n", "Z2e = R3 + R4 + 1j*w*L\n", " #primary current, I1\n", "I1 = E1/Z1e\n", " #E2\n", "E2 = 1j*w*M*I1\n", " #secondary current I2\n", "I2 = E2/Z2e\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"secondary current I2 is \",round(abs(I2)*1E3,3),\"/_\", round(cmath.phase(complex(I2.real,I2.imag))*180/math.pi,2),\"deg mA\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "secondary current I2 is 4.085 /_ 28.55 deg mA\n" ] } ], "prompt_number": 1 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 11, page no. 853

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 50;# in Volts\n", "thetae1 = 0;# in degrees\n", "w = 500;# in rad/sec\n", "R1 = 300;# in ohm\n", "L1 = 0.2;# in Henry\n", "L2 = 0.5;# in Henry\n", "L3 = 0.3;# in Henry\n", "R2 = 500;# in ohm\n", "C = 5E-6;# in farad\n", "M = 0.2;# in Henry\n", "\n", "#calculation:\n", " # Self impedance of primary circuit\n", "Z1 = R1 + 1j*w*(L1 + L2)\n", " #Self impedance of secondary circuit,\n", "Z2 = R2 + 1j*(w*L3 - 1/(w*C))\n", " #reflected impedance, Zr\n", "Zr = (w*M)**2/Z2\n", " #Effective primary impedance,\n", "Z1e = Z1 + Zr\n", " #Primary current I1 \n", "I1 = E1/Z1e\n", " #Secondary current I2\n", "E2 = 1j*w*M*I1\n", "I2 = E2/Z2\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n Self impedance of primary circuit, Z1 is \",Z1.real,\" + (\", Z1.imag,\")i ohm\"\n", "print \"\\n Self impedance of secondary circuit, Z2 is \",Z2.real,\" + (\", Z2.imag,\")i ohm\"\n", "print \"\\n reflected impedance, Zr is \",Zr.real,\" +(\", Zr.imag,\")i ohm\"\n", "print \"\\n Effective primary impedance Z1(eff) is \",Z1e.real,\" +(\",Z1e.imag,\")i ohm\"\n", "print \"\\n primary current I1 is \",round(abs(I1),2),\"/_\",round(cmath.phase(complex(I1.real,I1.imag))*180/math.pi,2),\"deg A\"\n", "print \"\\n secondary current I2 is \",round(abs(I2),2),\"/_\",round(cmath.phase(complex(I2.real,I2.imag))*180/math.pi,2),\"deg A\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " Self impedance of primary circuit, Z1 is 300.0 + ( 350.0 )i ohm\n", "\n", " Self impedance of secondary circuit, Z2 is 500.0 + ( -250.0 )i ohm\n", "\n", " reflected impedance, Zr is 16.0 +( 8.0 )i ohm\n", "\n", " Effective primary impedance Z1(eff) is 316.0 +( 358.0 )i ohm\n", "\n", " primary current I1 is 0.1 /_ -48.57 deg A\n", "\n", " secondary current I2 is 0.02 /_ 68.0 deg A" ] } ], "prompt_number": 11 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 12, page no. 855

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 20;# in Volts\n", "thetae1 = 0;# in degrees\n", "R1 = 15;# in ohm\n", "C1 = 400E-12;# in farad\n", "R2 = 30;# in ohm\n", "L1 = 0.001;# in Henry\n", "L2 = 0.0002;# in Henry\n", "R3 = 50;# in ohm\n", "M = 10E-6;# in Henry\n", "\n", "#calculation:\n", " #voltage\n", "E1 = E1*math.cos(thetae1*math.pi/180) + 1j*E1*math.sin(thetae1*math.pi/180)\n", " #the resonant frequency, fr \n", "fr = 1/(2*math.pi*(L1*C1)**0.5)\n", " #The secondary is also tuned to a resonant frequency\n", " #capacitance,C2\n", "C2 = 1/(L2*(2*math.pi*fr)**2)\n", " #the effective primary impedance Z1eff\n", "w = 2*math.pi*fr\n", "Z1e = R1 + R2 + ((w*M)**2)/R3\n", " #Primary current I1 \n", "I1 = E1/Z1e\n", " #Secondary current I2\n", "E2 = 1j*w*M*I1\n", "I2 = E2/Z1e\n", " #voltage across capacitor C2\n", "Vc2 = I2*(-1*1j/(w*C2))\n", " #coefficient of coupling, k \n", "k = M/(L1*L2)**0.5\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n the resonant frequency,fr is \",round(fr/1000,2),\"KHz\"\n", "print \"\\n capacitance,C2 is \",round(C2*1E9,2),\"nF\"\n", "print \"\\n Effective primary impedance Z1(eff) is \",round(abs(Z1e),2),\" ohm\"\n", "print \"\\n primary current I1 is \",round(abs(I1),2),\"/_\",round(cmath.phase(complex(I1.real,I1.imag)),0),\"deg A\"\n", "print \"\\n voltage across capacitor C2 is \",round(abs(Vc2),2),\"/_\",round(abs(cmath.phase(complex(Vc2.real,Vc2.imag))),0),\"deg V\"\n", "print \"\\n coefficient of coupling, k is \",round(k,4),\"\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " the resonant frequency,fr is 251.65 KHz\n", "\n", " capacitance,C2 is 2.0 nF\n", "\n", " Effective primary impedance Z1(eff) is 50.0 ohm\n", "\n", " primary current I1 is 0.4 /_ 0.0 deg A\n", "\n", " voltage across capacitor C2 is 40.0 /_ 0.0 deg V\n", "\n", " coefficient of coupling, k is 0.0224 \n" ] } ], "prompt_number": 2 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 13, page no. 858

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 250;# in Volts\n", "thetae1 = 0;# in degrees\n", "R1 = 50j;# in ohm\n", "R2 = 10;# in ohm\n", "R3 = 10;# in ohm\n", "R4 = 50j;# in ohm\n", "R5 = 50;# in ohm\n", "M = 10j;# in ohm\n", "\n", " #calculation:\n", " #voltage\n", "E1 = E1*math.cos(thetae1*math.pi/180) + 1j*E1*math.sin(thetae1*math.pi/180)\n", " #Applying Kirchhoff\u2019s voltage law to the primary circuit gives\n", " #(R1 + R2)*I1 - M*I2 = E1\n", " #Applying Kirchhoff\u2019s voltage law to the secondary circuit gives\n", " #-1*M*I1 + ( R3 + R4 + R5)*I2 = 0\n", " #solving these two\n", "I2 = E1/((R1 + R2)*(R3 + R4 + R5)/(-1*M) + (-1*M))\n", "I1 = I2*(R3 + R4 + R5)/(-1*M)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n primary current I1 is \",round(I1.real,2),\" +(\",round( I1.imag,2),\")i A\"\n", "print \"\\n secondary current I2 is \",round(I2.real,2),\" +(\",round( I2.imag,2),\")i A\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " primary current I1 is 0.85 +( -4.77 )i A\n", "\n", " secondary current I2 is -0.54 +( 0.31 )i A" ] } ], "prompt_number": 13 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 14, page no. 859

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 40;# in Volts\n", "thetae1 = 0;# in degrees\n", "R1 = 5;# in ohm\n", "L1 = 0.001;# in Henry\n", "L2 = 0.006;# in Henry\n", "R2 = 40;# in ohm\n", "rzl = 200;# in ohm\n", "thetazl = -60;# in degrees\n", "k = 0.70\n", "f = 20000;# in Hz\n", "\n", " #calculation:\n", "w = 2*math.pi*f\n", " #voltage\n", "#E1 = E1*math.cos(thetae1*math.pi/180) + 1j*E1*math.sin(thetae1*math.pi/180)\n", " #impedance\n", "ZL = rzl*math.cos(thetazl*math.pi/180) + 1j*rzl*math.sin(thetazl*math.pi/180)\n", " #mutual inductance, M\n", "M = k*(L1*L2)**0.5\n", " #Applying Kirchhoff\u00e2\u20ac\u2122s voltage law to the primary circuit gives\n", " #(R1 + 1j*w*L1)*I1 - 1j*w*M*I2 = E1\n", " #Applying Kirchhoff\u00e2\u20ac\u2122s voltage law to the secondary circuit gives\n", " #-1j*w*M*I1 + ( R2 + ZL + 1j*w*L2)*I2 = 0\n", " #solving these two\n", "\n", "a = R1 + 1j*w*L1\n", "b = 1j*w*M\n", "c = R2 + ZL + 1j*w*L2\n", "I1 = E1/(1*a - (b**2)/c)\n", "d = -1*cmath.phase(complex(I1.real,I1.imag))\n", "e = abs(I1)\n", "I2 = (b/c)*(e*math.cos(d) + 1j*e*math.sin(d))\n", "pd2 = I2*ZL\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n mutual induction M is \",round(M*1E3,3),\"mH\"\n", "print \"\\n primary current I1 is \",round(abs(I1),3),\"/_\",round(-1*cmath.phase(complex(I1.real,I1.imag))*180/math.pi,2),\"deg A\"\n", "print \"\\n secondary current I2 is \",round(abs(pd2),1),\"/_\",round(cmath.phase(complex(pd2.real,pd2.imag))*180/math.pi,2),\"deg V\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " mutual induction M is 1.715 mH\n", "\n", " primary current I1 is 0.724 /_ 65.15 deg A\n", "\n", " secondary current I2 is 52.2 /_ 18.7 deg V" ] } ], "prompt_number": 2 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 15, page no. 860

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 50;# in Volts\n", "thetae1 = 0;# in degrees\n", "r = 5;# in ohm\n", "R1 = 20;# in ohm\n", "L1 = 0.2;# in Henry\n", "L2 = 0.4;# in Henry\n", "R2 = 25;# in ohm\n", "RL = 20;# in ohm\n", "M = 0.1;# in Henry\n", "f = 75/math.pi;# in Hz\n", "\n", "#calculation:\n", "w = 2*math.pi*f\n", " #Applying Kirchhoff\u2019s voltage law to the primary circuit gives\n", " #(r + R1 + 1j*w*L1)*I1 - 1j*w*M*I2 = E1\n", " #Applying Kirchhoff\u2019s voltage law to the secondary circuit gives\n", " #-1*1j*w*M*I1 + ( R2 + RL + 1j*w*L2)*I2 = 0\n", " #solving these two\n", "I2 = E1/((r + R1 + 1j*w*L1)*(R2 + RL + 1j*w*L2)/(1j*w*M) + (-1*1j*w*M))\n", "I1 = I2*(R2 + RL + 1j*w*L2)/(1j*w*M)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"\\n primary current I1 is \",round(abs(I1),2),\"/_\",round(cmath.phase(complex(I1.real,I1.imag))*180/math.pi,2),\"deg A\"\n", "print \"\\n load current I2 is \",round(abs(I2),2),\"/_\",round(cmath.phase(complex(I2.real,I2.imag))*180/math.pi,2),\"deg A\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "\n", " primary current I1 is 1.3 /_ -45.84 deg A\n", "\n", " load current I2 is 0.26 /_ -8.97 deg A" ] } ], "prompt_number": 15 }, { "cell_type": "markdown", "metadata": {}, "source": [ "

Example 16, page no. 862

" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "from __future__ import division\n", "import math\n", "import cmath\n", "#initializing the variables:\n", "E1 = 50;# in Volts\n", "thetae1 = 0;# in degrees\n", "r = 5;# in ohm\n", "R1 = 20;# in ohm\n", "L1 = 0.2;# in Henry\n", "R = 8;# in ohm\n", "L = 0.1;# in Henry\n", "L2 = 0.4;# in Henry\n", "R2 = 25;# in ohm\n", "RL = 20;# in ohm\n", "M = 0.1;# in Henry\n", "f = 75/math.pi;# in Hz\n", "\n", "#calculation:\n", "w = 2*math.pi*f\n", " #Applying Kirchhoff\u2019s voltage law to the primary circuit gives\n", " #(r + R1 + 1j*w*L1 + R + 1j*w*L)*I1 - (1j*w*M + R + 1j*w*L)*I2 = E1\n", " #Applying Kirchhoff\u2019s voltage law to the secondary circuit gives\n", " #-1*(1j*w*M + R + 1j*w*L)*I1 + (R2 + RL + 1j*w*L2 + R + 1j*w*L)*I2 = 0\n", " #solving these two\n", "I2 = E1/((r + R1 + 1j*w*L1 + R + 1j*w*L)*(R2 + RL + 1j*w*L2 + R + 1j*w*L)/(1j*w*M + R + 1j*w*L) + (-1*(1j*w*M + R + 1j*w*L)))\n", "I1 = I2*(R2 + RL + 1j*w*L2 + R + 1j*w*L)/(1j*w*M + R + 1j*w*L)\n", " #reversing\n", " #Applying Kirchhoff\u2019s voltage law to the primary circuit gives\n", " #(r + R1 + 1j*w*L1 + R + 1j*w*L)*I1r - (-1*1j*w*M + R + 1j*w*L)*I2r = E1\n", " #Applying Kirchhoff\u2019s voltage law to the secondary circuit gives\n", " #-1*(-1*1j*w*M + R + 1j*w*L)*I1r + (R2 + RL + 1j*w*L2 + R + 1j*w*L)*I2r = 0\n", " #solving these two\n", "I2r = E1/((r + R1 + 1j*w*L1 + R + 1j*w*L)*(R2 + RL + 1j*w*L2 + R + 1j*w*L)/(-1*1j*w*M + R + 1j*w*L) + (-1*(-1*1j*w*M + R + 1j*w*L)))\n", "I1r = I2r*(R2 + RL + 1j*w*L2 + R + 1j*w*L)/(-1*1j*w*M + R + 1j*w*L)\n", "\n", "\n", "#Results\n", "print \"\\n\\n Result \\n\\n\"\n", "print \"primary current I1 is \",round(abs(I1),2),\"/_\",round(cmath.phase(complex(I1.real,I1.imag))*180/math.pi,2),\"deg A\"\n", "print \"load current I2 is \",round(abs(I2),2),\"/_\",round(cmath.phase(complex(I2.real,I2.imag))*180/math.pi,2),\"deg A\"\n", "print \"reversed primary current I1r is \",round(abs(I1r),2),\"/_\",round(cmath.phase(complex(I1r.real,I1r.imag))*180/math.pi,2),\"deg A\"\n", "print \"reversed load current I2r is \",round(abs(I2r),2),\"/_\",round(cmath.phase(complex(I2r.real,I2r.imag))*180/math.pi,2),\"deg A\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "\n", " Result \n", "\n", "\n", "primary current I1 is 1.03 /_ -45.47 deg A\n", "load current I2 is 0.35 /_ -25.16 deg A\n", "reversed primary current I1r is 0.89 /_ -54.42 deg A\n", "reversed load current I2r is 0.08 /_ -109.17 deg A\n" ] } ], "prompt_number": 3 } ], "metadata": {} } ] }