{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 06 : Phase Controlled Rectifiers" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.1, Page No 283" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0\n", "P=1000.0\n", "R=V**2/P\n", "\n", "#Calculations\n", "a=math.pi/4\n", "V_or1=(math.sqrt(2)*V/(2*math.sqrt(math.pi)))*math.sqrt((math.pi-a)+.5*math.sin(2*a))\n", "P1=V_or1**2/R \n", "a=math.pi/2\n", "V_or2=(math.sqrt(2)*V/(2*math.sqrt(math.pi)))*math.sqrt((math.pi-a)+.5*math.sin(2*a))\n", "P2=V_or2**2/R \n", "\n", "#Results\n", "print(\"when firing angle delay is of 45deg\")\n", "print(\"power absorbed=%.2f W\" %P1)\n", "print(\"when firing angle delay is of 90deg\")\n", "print(\"power absorbed=%.2f W\" %P2)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "when firing angle delay is of 45deg\n", "power absorbed=454.58 W\n", "when firing angle delay is of 90deg\n", "power absorbed=250.00 W\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.2, Page No 283" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0\n", "E=150.0\n", "R=8.0\n", "\n", "#Calculations\n", "th1=math.sin(math.radians(E/(math.sqrt(2)*V)))\n", "I_o=(1/(2*math.pi*R))*(2*math.sqrt(2)*230*math.cos(math.radians(th1))-E*(math.pi-2*th1*math.pi/180)) \n", "P=E*I_o \n", "I_or=math.sqrt((1/(2*math.pi*R**2))*((V**2+E**2)*(math.pi-2*th1*math.pi/180)+V**2*math.sin(math.radians(2*th1))-4*math.sqrt(2)*V*E*math.cos(math.radians(th1))))\n", "P_r=I_or**2*R \n", "pf=(P+P_r)/(V*I_or)\n", "\n", "#Results\n", "print(\"avg charging curent=%.4f A\" %I_o)\n", "print(\"power supplied to the battery=%.2f W\" %P)\n", "print(\"power dissipated by the resistor=%.3f W\" %P_r) \n", "print(\"supply pf=%.3f\" %pf)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "avg charging curent=3.5679 A\n", "power supplied to the battery=535.18 W\n", "power dissipated by the resistor=829.760 W\n", "supply pf=0.583\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.3 Page No 284" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0\n", "E=150.0\n", "R=8.0\n", "a=35.0\n", "\n", "#Calculations\n", "th1=math.degrees(math.asin(E/(math.sqrt(2)*V)))\n", "th2=180-th1\n", "I_o=(1/(2*math.pi*R))*(math.sqrt(2)*230*(math.cos(math.radians(a))-math.cos(math.radians(th2)))-E*((th2-a)*math.pi/180)) \n", "P=E*I_o \n", "I_or=math.sqrt((1/(2*math.pi*R**2))*((V**2+E**2)*((th2-a)*math.pi/180)-(V**2/2)*(math.sin(math.radians(2*th2))-math.sin(math.radians(2*a)))-2*math.sqrt(2)*V*E*(math.cos(math.radians(a))-math.cos(math.radians(th2)))))\n", "P_r=I_or**2*R \n", "pf=(P+P_r)/(V*I_or) \n", "\n", "\n", "#Results\n", "print(\"avg charging curent=%.4f A\" %I_o)\n", "print(\"power supplied to the battery=%.2f W\" %P)\n", "print(\"power dissipated by the resistor=%.2f W\" %P_r)\n", "print(\"supply pf=%.4f\" %pf)\n", " #Answers have small variations from that in the book due to difference in the rounding off of digits." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "avg charging curent=4.9208 A\n", "power supplied to the battery=738.12 W\n", "power dissipated by the resistor=689.54 W\n", "supply pf=0.6686\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.4, Page No 285" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "B=210\n", "f=50.0 #Hz\n", "w=2*math.pi*f\n", "a=40.0 #firing angle\n", "V=230.0\n", "R=5.0\n", "L=2*10**-3\n", "\n", "#Calculations\n", "t_c1=(360-B)*math.pi/(180*w) \n", "V_o1=(math.sqrt(2)*230/(2*math.pi))*(math.cos(math.radians(a))-math.cos(math.radians(B))) \n", "I_o1=V_o1/R \n", "E=110\n", "R=5\n", "L=2*10**-3\n", "th1=math.degrees(math.asin(E/(math.sqrt(2)*V)))\n", "t_c2=(360-B+th1)*math.pi/(180*w) \n", "V_o2=(math.sqrt(2)*230/(2*math.pi))*(math.cos(math.radians(a))-math.cos(math.radians(B))) \n", "I_o2=(1/(2*math.pi*R))*(math.sqrt(2)*230*(math.cos(math.radians(a))-math.cos(math.radians(B)))-E*((B-a)*math.pi/180)) \n", "V_o2=R*I_o2+E \n", "\n", "\n", "#Results\n", "print(\"for R=5ohm and L=2mH\")\n", "print(\"ckt turn off time=%.3f msec\" %(t_c1*1000))\n", "print(\"avg output voltage=%.3f V\" %V_o1)\n", "print(\"avg output current=%.4f A\" %I_o1)\n", "print(\"for R=5ohm % L=2mH and E=110V\")\n", "print(\"ckt turn off time=%.3f msec\" %(t_c2*1000))\n", "print(\"avg output current=%.4f A\" %I_o2)\n", "print(\"avg output voltage=%.3f V\" %V_o2) " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "for R=5ohm and L=2mH\n", "ckt turn off time=8.333 msec\n", "avg output voltage=84.489 V\n", "avg output current=16.8979 A\n", "for R=5ohm % L=2mH and E=110V\n", "ckt turn off time=9.431 msec\n", "avg output current=6.5090 A\n", "avg output voltage=142.545 V\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.5 Page No 286" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V_s=230.0\n", "f=50.0\n", "R=10.0\n", "a=60.0\n", "\n", "#Calculations\n", "V_m=(math.sqrt(2)*V_s)\n", "V_o=V_m/(2*math.pi)*(1+math.cos(math.radians(a)))\n", "I_o=V_o/R\n", "V_or=(V_m/(2*math.sqrt(math.pi)))*math.sqrt((math.pi-a*math.pi/180)+.5*math.sin(math.radians(2*a)))\n", "I_or=V_or/R\n", "P_dc=V_o*I_o\n", "P_ac=V_or*I_or\n", "RE=P_dc/P_ac \n", "FF=V_or/V_o \n", "VRF=math.sqrt(FF**2-1) \n", "TUF=P_dc/(V_s*I_or) \n", "PIV=V_m \n", "\n", "\n", "#Results\n", "print(\"rectification efficiency=%.4f\" %RE)\n", "print(\"form factor=%.3f\" %FF)\n", "print(\"voltage ripple factor=%.4f\" %VRF)\n", "print(\"t/f utilisation factor=%.4f\" %TUF)\n", "print(\"PIV of thyristor=%.2f V\" %PIV)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "rectification efficiency=0.2834\n", "form factor=1.879\n", "voltage ripple factor=1.5903\n", "t/f utilisation factor=0.1797\n", "PIV of thyristor=325.27 V\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.6 Page No 294" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=1000.0\n", "fos=2.5 #factor of safety\n", "I_TAV=40.0\n", "\n", "#Calculations\n", "V_m1=V/(2*fos)\n", "P1=(2*V_m1/math.pi)*I_TAV \n", "V_m2=V/(fos)\n", "P2=(2*V_m2/math.pi)*I_TAV \n", "\n", "#Results\n", "print(\"for mid pt convertor\")\n", "print(\"power handled=%.3f kW\" %(P1/1000))\n", "print(\"for bridge convertor\")\n", "print(\"power handled=%.3f kW\" %(P2/1000))\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "for mid pt convertor\n", "power handled=5.093 kW\n", "for bridge convertor\n", "power handled=10.186 kW\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.7, Page No 297" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V_s=230.0\n", "V_m=math.sqrt(2)*V_s\n", "R=.4\n", "I_o=10\n", "I_or=I_o\n", "E=120.0\n", "\n", "#Calculations\n", "a1=math.degrees(math.acos((E+I_o*R)*math.pi/(2*V_m)))\n", "pf1=(E*I_o+I_or**2*R)/(V_s*I_or) \n", "E=-120.0\n", "a2=math.degrees(math.acos((E+I_o*R)*math.pi/(2*V_m))) \n", "pf2=(-E*I_o-I_or**2*R)/(V_s*I_or) \n", "\n", "#Results\n", "print(\"firing angle delay=%.2f deg\" %a1)\n", "print(\"pf=%.4f\" %pf1)\n", "print(\"firing angle delay=%.2f deg\" %a2)\n", "print(\"pf=%.4f\" %pf2)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "firing angle delay=53.21 deg\n", "pf=0.5391\n", "firing angle delay=124.07 deg\n", "pf=0.5043\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.9 Page No 299" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V_s=230.0\n", "f=50.0\n", "a=45.0\n", "R=5.0\n", "E=100.0\n", "\n", "#Calculations\n", "V_o=((math.sqrt(2)*V_s)/(2*math.pi))*(3+math.cos(math.radians(a)))\n", "I_o=(V_o-E)/R \n", "P=E*I_o \n", "\n", "#Results\n", "print(\"avg o/p current=%.3f A\" %I_o)\n", "print(\"power delivered to battery=%.4f kW\" %(P/1000))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "avg o/p current=18.382 A\n", "power delivered to battery=1.8382 kW\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.10 Page No 300" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variablesV_s=230\n", "f=50.0\n", "a=50.0\n", "R=6.0\n", "E=60.0\n", "V_o1=((math.sqrt(2)*2*V_s)/(math.pi))*math.cos(math.radians(a))\n", "I_o1=(V_o1-E)/R \n", "\n", "#ATQ after applying the conditions\n", "V_o2=((math.sqrt(2)*V_s)/(math.pi))*math.cos(math.radians(a))\n", "I_o2=(V_o2-E)/R \n", "\n", "print(\"avg o/p current=%.3f A\" %I_o1)\n", "print(\"avg o/p current after change=%.2f A\" %I_o2)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "avg o/p current=12.184 A\n", "avg o/p current after change=1.09 A\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.11 Page No 309" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V_s=230.0\n", "V_m=math.sqrt(2)*V_s\n", "a=45.0\n", "R=10.0\n", "\n", "#Calculations\n", "V_o=(2*V_m/math.pi)*math.cos(math.radians(a))\n", "I_o=V_o/R\n", "V_or=V_m/math.sqrt(2)\n", "I_or=I_o\n", "P_dc=V_o*I_o\n", "P_ac=V_or*I_or\n", "RE=P_dc/P_ac \n", "FF=V_or/V_o \n", "VRF=math.sqrt(FF**2-1) \n", "I_s1=2*math.sqrt(2)*I_o/math.pi\n", "DF=math.cos(math.radians(a))\n", "CDF=.90032\n", "pf=CDF*DF \n", "HF=math.sqrt((1/CDF**2)-1) \n", "Q=2*V_m*I_o*math.sin(math.radians(a))/math.pi \n", "\n", "#Results\n", "print(\"rectification efficiency=%.4f\" %RE)\n", "print(\"form factor=%.4f\" %FF)\n", "print(\"voltage ripple factor=%.4f\" %VRF)\n", "print(\"pf=%.5f\" %pf)\n", "print(\"HF=%.5f\" %HF)\n", "print(\"active power=%.2f W\" %P_dc) \n", "print(\"reactive power=%.3f Var\" %Q)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "rectification efficiency=0.6366\n", "form factor=1.5708\n", "voltage ripple factor=1.2114\n", "pf=0.63662\n", "HF=0.48342\n", "active power=2143.96 W\n", "reactive power=2143.956 Var\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.12, Page No 310" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V_s=230.0\n", "V_m=math.sqrt(2)*V_s\n", "a=45.0\n", "R=10.0\n", "\n", "#Calculations\n", "V_o=(V_m/math.pi)*(1+math.cos(math.radians(a)))\n", "I_o=V_o/R\n", "V_or=V_s*math.sqrt((1/math.pi)*((math.pi-a*math.pi/180)+math.sin(math.radians(2*a))/2))\n", "I_or=I_o\n", "P_dc=V_o*I_o\n", "P_ac=V_or*I_or\n", "RE=P_dc/P_ac \n", "FF=V_or/V_o \n", "VRF=math.sqrt(FF**2-1) \n", "I_s1=2*math.sqrt(2)*I_o*math.cos(math.radians(a/2))/math.pi\n", "DF=math.cos(math.radians(a/2)) \n", "CDF=2*math.sqrt(2)*math.cos(math.radians(a/2))/math.sqrt(math.pi*(math.pi-a*math.pi/180)) \n", "pf=CDF*DF \n", "HF=math.sqrt((1/CDF**2)-1) \n", "Q=V_m*I_o*math.sin(math.radians(a))/math.pi\n", "\n", "#Results\n", "print(\"form factor=%.3f\" %FF)\n", "print(\"rectification efficiency=%.4f\" %RE)\n", "print(\"voltage ripple factor=%.3f\" %VRF) \n", "print(\"DF=%.4f\" %DF)\n", "print(\"CDF=%.4f\" %CDF)\n", "print(\"pf=%.4f\" %pf)\n", "print(\"HF=%.4f\" %HF)\n", "print(\"active power=%.3f W\" %P_dc)\n", "print(\"reactive power=%.2f Var\" %Q)\n", " #Answers have small variations from that in the book due to difference in the rounding off of digits." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "form factor=1.241\n", "rectification efficiency=0.8059\n", "voltage ripple factor=0.735\n", "DF=0.9239\n", "CDF=0.9605\n", "pf=0.8874\n", "HF=0.2899\n", "active power=3123.973 W\n", "reactive power=1293.99 Var\n" ] } ], "prompt_number": 11 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.13, Page No 319" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V_s=230.0\n", "R=10.0\n", "\n", "#Calculations\n", "V_ml=math.sqrt(2)*V_s\n", "V_om=3*V_ml/(2*math.pi)\n", "V_o=V_om/2\n", "th=30\n", "a=math.degrees(math.acos((2*math.pi*math.sqrt(3)*V_o/(3*V_ml)-1)))-th \n", "I_o=V_o/R \n", "V_or=V_ml/(2*math.sqrt(math.pi))*math.sqrt((5*math.pi/6-a*math.pi/180)+.5*math.sin(math.radians(2*a+2*th)))\n", "I_or=V_or/R \n", "RE=V_o*I_o/(V_or*I_or) \n", "\n", "#Results\n", "print(\"delay angle=%.1f deg\" %a)\n", "print(\"avg load current=%.3f A\" %I_o)\n", "print(\"rms load current=%.3f A\" %I_or)\n", "print(\"rectification efficiency=%.4f\" %RE)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "delay angle=67.7 deg\n", "avg load current=7.765 A\n", "rms load current=10.477 A\n", "rectification efficiency=0.5494\n" ] } ], "prompt_number": 12 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.15, Page No 321" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=400.0\n", "V_ml=math.sqrt(2)*V\n", "v_T=1.4\n", "a1=30.0\n", "\n", "#Calculations\n", "V_o1=3*V_ml/(2*math.pi)*math.cos(math.radians(a1))-v_T \n", "a2=60.0\n", "V_o2=3*V_ml/(2*math.pi)*math.cos(math.radians(a2))-v_T \n", "I_o=36\n", "I_TA=I_o/3 \n", "I_Tr=I_o/math.sqrt(3) \n", "P=I_TA*v_T \n", "\n", "#Results\n", "print(\"for firing angle = 30deg\")\n", "print(\"avg output voltage=%.3f V\" %V_o1)\n", "print(\"for firing angle = 60deg\")\n", "print(\"avg output voltage=%.2f V\" %V_o2)\n", "print(\"avg current rating=%.0f A\" %I_TA)\n", "print(\"rms current rating=%.3f A\" %I_Tr)\n", "print(\"PIV of SCR=%.1f V\" %V_ml)\n", "print(\"power dissipated=%.1f W\" %P)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "for firing angle = 30deg\n", "avg output voltage=232.509 V\n", "for firing angle = 60deg\n", "avg output voltage=133.65 V\n", "avg current rating=12 A\n", "rms current rating=20.785 A\n", "PIV of SCR=565.7 V\n", "power dissipated=16.8 W\n" ] } ], "prompt_number": 13 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.17, Page No 331" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "E=200\n", "I_o=20\n", "R=.5\n", "\n", "#Calculations\n", "V_o1=E+I_o*R\n", "V_s=230\n", "V_ml=math.sqrt(2)*V_s\n", "a1=math.degrees(math.acos(V_o1*math.pi/(3*V_ml)))\n", "th=120\n", "I_s=math.sqrt((1/math.pi)*I_o**2*th*math.pi/180)\n", "P=E*I_o+I_o**2*R\n", "pf=P/(math.sqrt(3)*V_s*I_s) \n", "V_o2=E-I_o*R\n", "a2=math.degrees(math.acos(-V_o2*math.pi/(3*V_ml))) \n", "\n", "#Results\n", "print(\"firing angle delay=%.3f deg\" %a1)\n", "print(\"pf=%.3f\" %pf)\n", "print(\"firing angle delay=%.2f deg\" %a2)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "firing angle delay=47.461 deg\n", "pf=0.646\n", "firing angle delay=127.71 deg\n" ] } ], "prompt_number": 14 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.18, Page No 332" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0\n", "f=50.0\n", "\n", "#Calculations\n", "w=2*math.pi*f\n", "a1=0\n", "t_c1=(4*math.pi/3-a1*math.pi/180)/w \n", "a2=30\n", "t_c2=(4*math.pi/3-a2*math.pi/180)/w \n", "\n", "#Results\n", "print(\"for firing angle delay=0deg\")\n", "print(\"commutation time=%.2f ms\" %(t_c1*1000))\n", "print(\"peak reverse voltage=%.2f V\" %(math.sqrt(2)*V))\n", "print(\"for firing angle delay=30deg\")\n", "print(\"commutation time=%.2f ms\" %(t_c2*1000))\n", "print(\"peak reverse voltage=%.2f V\" %(math.sqrt(2)*V))\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "for firing angle delay=0deg\n", "commutation time=13.33 ms\n", "peak reverse voltage=325.27 V\n", "for firing angle delay=30deg\n", "commutation time=11.67 ms\n", "peak reverse voltage=325.27 V\n" ] } ], "prompt_number": 15 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.19, Page No 333" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "a=30.0\n", "R=10.0\n", "P=5000.0\n", "\n", "#Calculations\n", "V_s=math.sqrt(P*R*2*math.pi/(2*3)/(math.pi/3+math.sqrt(3)*math.cos(math.radians(2*a))/2))\n", "V_ph=V_s/math.sqrt(3) \n", "I_or=math.sqrt(P*R)\n", "V_s=I_or*math.pi/(math.sqrt(2)*3*math.cos(math.radians(a)))\n", "V_ph=V_s/math.sqrt(3) \n", "\n", "#Results\n", "print(\"per phase voltage percent V_ph=%.3f V\" %V_ph) \n", "print(\"for constant load current\")\n", "print(\"V_ph=%.2f V\" %V_ph)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "per phase voltage percent V_ph=110.384 V\n", "for constant load current\n", "V_ph=110.38 V\n" ] } ], "prompt_number": 16 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.20, Page No 334" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "a=30.0\n", "R=10.0\n", "P=5000.0\n", "\n", "#Calculations\n", "V_s=math.sqrt(P*R*4*math.pi/(2*3)/(2*math.pi/3+math.sqrt(3)*(1+math.cos(math.radians(2*a)))/2))\n", "V_ph=V_s/math.sqrt(3) \n", "I_or=math.sqrt(P*R)\n", "V_s=I_or*2*math.pi/(math.sqrt(2)*3*(1+math.cos(math.radians(a))))\n", "V_ph=V_s/math.sqrt(3) \n", "\n", "#Results\n", "print(\"per phase voltage percent V_ph=%.3f V\" %V_ph) \n", "print(\"for constant load current\")\n", "print(\"V_ph=%.2f V\" %V_ph)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "per phase voltage percent V_ph=102.459 V\n", "for constant load current\n", "V_ph=102.46 V\n" ] } ], "prompt_number": 17 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.21, Page No 334" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "a=90.0\n", "R=10.0\n", "P=5000.0\n", "\n", "#Calculations\n", "V_s=math.sqrt(P*R*4*math.pi/(2*3)/((math.pi-math.pi/2)+(math.sin(math.radians(2*a)))/2))\n", "V_ph=V_s/math.sqrt(3) \n", "I_or=math.sqrt(P*R)\n", "V_s=I_or*2*math.pi/(math.sqrt(2)*3*(1+math.cos(math.radians(a))))\n", "V_ph=V_s/math.sqrt(3) \n", "\n", "#Results\n", "print(\"per phase voltage percent V_ph=%.2f V\" %V_ph)\n", "print(\"for constant load current\")\n", "print(\"V_ph=%.1f V\" %V_ph)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "per phase voltage percent V_ph=191.19 V\n", "for constant load current\n", "V_ph=191.2 V\n" ] } ], "prompt_number": 18 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.22 Page No 334" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "E=200.0\n", "I_o=20.0\n", "R=.5\n", "\n", "#Calculations\n", "V_o=E+I_o*R\n", "V_s=230\n", "V_ml=math.sqrt(2)*V_s\n", "a=math.degrees(math.acos(V_o*2*math.pi/(3*V_ml)-1)) \n", "a1=180-a\n", "I_sr=math.sqrt((1/math.pi)*I_o**2*(a1*math.pi/180))\n", "P=V_o*I_o\n", "pf=P/(math.sqrt(3)*V_s*I_sr) \n", "\n", "#Results\n", "print(\"firing angle delay=%.2f deg\" %a)\n", "print(\"pf=%.2f\" %pf)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "firing angle delay=69.38 deg\n", "pf=0.67\n" ] } ], "prompt_number": 19 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.23, Page No 335" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V_s=400.0\n", "f=50.0\n", "I_o=15.0\n", "a=45.0\n", "\n", "#Calculations\n", "I_TA=I_o*120.0/360.0\n", "I_Tr=math.sqrt(I_o**2*120/360)\n", "I_sr=math.sqrt(I_o**2*120/180)\n", "V_ml=math.sqrt(2)*V_s\n", "V_o=3*V_ml*math.cos(math.radians(a))/math.pi\n", "V_or=V_ml*math.sqrt((3/(2*math.pi))*(math.pi/3+math.sqrt(3/2)*math.cos(math.radians(2*a))))\n", "I_or=I_o\n", "P_dc=V_o*I_o\n", "P_ac=V_or*I_or\n", "RE=P_dc/P_ac \n", "VA=3*V_s/math.sqrt(3)*I_sr\n", "TUF=P_dc/VA \n", "pf=P_ac/VA \n", "\n", "#Results\n", "print(\"rectification efficiency=%.5f\" %RE)\n", "print(\"TUF=%.4f\" %TUF)\n", "print(\"Input pf=%.3f\" %pf)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "rectification efficiency=0.95493\n", "TUF=0.6752\n", "Input pf=0.707\n" ] } ], "prompt_number": 20 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.24, Page No 341" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "I=10.0\n", "a=45.0\n", "V=400.0\n", "f=50.0\n", "\n", "#Calculations\n", "DF=math.cos(math.radians(a))\n", "I_o=10\n", "I_s1=4*I_o/(math.sqrt(2)*math.pi)*math.sin(math.pi/3)\n", "I_sr=I_o*math.sqrt(2.0/3.0)\n", "I_o=1 #suppose\n", "CDF=I_s1/I_sr \n", "THD=math.sqrt(1/CDF**2-1) \n", "pf=CDF*DF \n", "P=(3*math.sqrt(2)*V*math.cos(math.radians(a))/math.pi)*I\n", "Q=(3*math.sqrt(2)*V*math.sin(math.radians(a))/math.pi)*I \n", " \n", "#Results\n", "print(\"DF=%.3f\" %DF)\n", "print(\"CDF=%.3f\" %CDF)\n", "print(\"THD=%.5f\" %THD)\n", "print(\"PF=%.4f\" %pf)\n", "print(\"active power=%.2f W\" %P) \n", "print(\"reactive power=%.2f Var\" %Q)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "DF=0.707\n", "CDF=0.955\n", "THD=0.31084\n", "PF=0.6752\n", "active power=3819.72 W\n", "reactive power=3819.72 Var\n" ] } ], "prompt_number": 21 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.25, Page No 342" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "print(\"for firing angle=30deg\")\n", "a=30.0\n", "V=400.0\n", "V_ml=math.sqrt(2)*V\n", "V_o=3*V_ml*math.cos(math.radians(a))/math.pi\n", "E=350\n", "R=10\n", "\n", "#Calculations\n", "I_o=(V_o-E)/R\n", "I_or=I_o\n", "P1=V_o*I_o \n", "I_sr=I_o*math.sqrt(2.0/3.0)\n", "VA=3*V/math.sqrt(3)*I_sr\n", "pf=P1/VA \n", "a=180-60\n", "V=400\n", "V_ml=math.sqrt(2)*V\n", "V_o=3*V_ml*math.cos(math.radians(a))/math.pi\n", "E=-350\n", "R=10\n", "I_o=(V_o-E)/R\n", "I_or=I_o\n", "P2=-V_o*I_o \n", "I_sr=I_o*math.sqrt(2.0/3.0)\n", "VA=3*V/math.sqrt(3)*I_sr\n", "pf=P2/VA \n", "\n", "print(\"power delivered to load=%.2f W\" %P1)\n", "print(\"pf=%.4f\" %pf)\n", "print(\"for firing advance angle=60deg\")\n", "print(\"power delivered to load=%.2f W\" %P2)\n", "print(\"pf=%.4f\" %pf)\n", " #Answers have small variations from that in the book due to difference in the rounding off of digits.\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "for firing angle=30deg\n", "power delivered to load=5511.74 W\n", "pf=0.4775\n", "for firing advance angle=60deg\n", "power delivered to load=2158.20 W\n", "pf=0.4775\n" ] } ], "prompt_number": 22 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.26, Page No 347" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "a=0\n", "u=15.0\n", "\n", "#Calculations\n", "i=math.cos(math.radians(a))-math.cos(math.radians(a+u))\n", "a=30\n", "u=math.degrees(math.acos(math.cos(math.radians(a))-i))-a \n", "a=45\n", "u=math.degrees(math.acos(math.cos(math.radians(a))-i))-a \n", "a=60\n", "u=math.degrees(math.acos(math.cos(math.radians(a))-i))-a \n", "\n", "#Results\n", "print(\"for firing angle=30deg\") \n", "print(\"overlap angle=%.1f deg\" %u)\n", "print(\"for firing angle=45deg\") \n", "print(\"overlap angle=%.1f deg\" %u)\n", "print(\"for firing angle=60deg\") \n", "print(\"overlap angle=%.2f deg\" %u)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "for firing angle=30deg\n", "overlap angle=2.2 deg\n", "for firing angle=45deg\n", "overlap angle=2.2 deg\n", "for firing angle=60deg\n", "overlap angle=2.23 deg\n" ] } ], "prompt_number": 23 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.28, Page No 352" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "E=400.0\n", "I_o=20.0\n", "R=1\n", "\n", "#Calculations\n", "V_o=E+I_o*R\n", "f=50.0\n", "w=2*math.pi*f\n", "L=.004\n", "V=230 #per phase voltage\n", "V_ml=math.sqrt(6)*V\n", "a=math.degrees(math.acos(math.pi/(3*V_ml)*(V_o+3*w*L*I_o/math.pi))) \n", "print(\"firing angle delay=%.3f deg\" %a)\n", "u=math.degrees(math.acos(math.pi/(3*V_ml)*(V_o-3*w*L*I_o/math.pi)))-a \n", "\n", "#Results\n", "print(\"overlap angle=%.2f deg\" %u)\n", "#Answers have small variations from that in the book due to difference in the rounding off of digits." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "firing angle delay=34.382 deg\n", "overlap angle=8.22 deg\n" ] } ], "prompt_number": 24 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.29, Page No 352" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=400.0\n", "f=50.0\n", "w=2*math.pi*f\n", "R=1\n", "E=230\n", "I=15.0\n", "\n", "#Calculations\n", "V_o=-E+I*R\n", "V_ml=math.sqrt(2)*V\n", "a=math.degrees(math.acos(V_o*2*math.pi/(3*V_ml))) \n", "L=0.004\n", "a=math.degrees(math.acos((2*math.pi)/(3*V_ml)*(V_o+3*w*L*I/(2*math.pi)))) \n", "u=math.degrees(math.acos(math.cos(math.radians(a))-3*f*L*I/V_ml))-a \n", "\n", "#Results\n", "print(\"firing angle=%.3f deg\" %a)\n", "print(\"firing angle delay=%.3f deg\" %a)\n", "print(\"overlap angle=%.3f deg\" %u)\n", " #Answers have small variations from that in the book due to difference in the rounding off of digits.\n", " \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "firing angle=139.702 deg\n", "firing angle delay=139.702 deg\n", "overlap angle=1.431 deg\n" ] } ], "prompt_number": 25 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.31, Page No 361" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0 #per phase\n", "f=50.0\n", "\n", "#Calculations\n", "V_ml=math.sqrt(3.0)*math.sqrt(2)*V\n", "w=2*math.pi*f\n", "a1=60.0\n", "L=0.015\n", "i_cp=(math.sqrt(3)*V_ml/(w*L))*(1-math.sin(math.radians(a1))) \n", "\n", "#Results\n", "print(\"circulating current=%.4f A\" %i_cp)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "circulating current=27.7425 A\n" ] } ], "prompt_number": 26 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.32, Page No 362" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0\n", "V_m=math.sqrt(2)*V\n", "a=30.0\n", "\n", "#Calculations\n", "V_o=2*V_m* math.cos(math.radians(a))/math.pi \n", "R=10\n", "I_o=V_o/R \n", "I_TA=I_o*math.pi/(2*math.pi) \n", "I_Tr=math.sqrt(I_o**2*math.pi/(2*math.pi)) \n", "I_s=math.sqrt(I_o**2*math.pi/(math.pi)) \n", "I_o=I_s\n", "pf=(V_o*I_o/(V*I_s)) \n", "\n", "#Results\n", "print(\"avg o/p voltage=%.3f V\" %V_o)\n", "print(\"avg o/p current=%.2f A\" %I_o)\n", "print(\"avg value of thyristor current=%.3f A\" %I_TA)\n", "print(\"rms value of thyristor current=%.2f A\" %I_Tr)\n", "print(\"pf=%.4f\" %pf)\n", " #Answers have small variations from that in the book due to difference in the rounding off of digits.\n", " \n", " \n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "avg o/p voltage=179.330 V\n", "avg o/p current=17.93 A\n", "avg value of thyristor current=8.967 A\n", "rms value of thyristor current=12.68 A\n", "pf=0.7797\n" ] } ], "prompt_number": 27 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.33, Page No 363" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0\n", "V_m=math.sqrt(2)*V\n", "a=30.0\n", "L=.0015\n", "\n", "#Calculations\n", "V_o=2*V_m* math.cos(math.radians(a))/math.pi \n", "R=10\n", "I_o=V_o/R \n", "f=50\n", "w=2*math.pi*f\n", "V_ox=2*V_m*math.cos(math.radians(a))/math.pi-w*L*I_o/math.pi \n", "u=math.degrees(math.acos(math.cos(math.radians(a))-I_o*w*L/V_m))-a \n", "I=I_o\n", "pf=V_o*I_o/(V*I) \n", "\n", "#Results\n", "print(\"avg o/p voltage=%.3f V\" %V_ox)\n", "print(\"angle of overlap=%.3f deg\" %u)\n", "print(\"pf=%.4f\" %pf)\n", " #Answers have small variations from that in the book due to difference in the rounding off of digits." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "avg o/p voltage=176.640 V\n", "angle of overlap=2.855 deg\n", "pf=0.7797\n" ] } ], "prompt_number": 28 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.34, Page No 364" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=415.0\n", "V_ml=math.sqrt(2)*V\n", "a1=35.0 #firing angle advance\n", "\n", "#Calculations\n", "a=180-a1\n", "I_o=80.0\n", "r_s=0.04\n", "v_T=1.5\n", "X_l=.25 #reactance=w*L\n", "E=-3*V_ml*math.cos(math.radians(a))/math.pi+2*I_o*r_s+2*v_T+3*X_l*I_o/math.pi \n", "\n", "#Results\n", "print(\"mean generator voltage=%.3f V\" %E)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "mean generator voltage=487.590 V\n" ] } ], "prompt_number": 29 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.35, Page No 364" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=415.0\n", "V_ml=math.sqrt(2)*V\n", "R=0.2\n", "I_o=80\n", "r_s=0.04\n", "v_T=1.5\n", "\n", "#Calculations\n", "X_l=.25 #reactance=w*L\n", "a=35\n", "E=-(-3*V_ml*math.cos(math.radians(a))/math.pi+I_o*R+2*I_o*r_s+2*v_T+3*X_l*I_o/math.pi) \n", "a1=35\n", "a=180-a1\n", "E=(-3*V_ml*math.cos(math.radians(a))/math.pi+I_o*R+2*I_o*r_s+2*v_T+3*X_l*I_o/math.pi) \n", "\n", "#Results\n", "print(\"when firing angle=35deg\") \n", "print(\"mean generator voltage=%.3f V\" %E)\n", "print(\"when firing angle advance=35deg\")\n", "print(\"mean generator voltage=%.3f V\" %E)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "when firing angle=35deg\n", "mean generator voltage=503.590 V\n", "when firing angle advance=35deg\n", "mean generator voltage=503.590 V\n" ] } ], "prompt_number": 30 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.36, Page No 365" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "R=5.0\n", "V=230.0\n", "\n", "#Calculations\n", "V_mp=math.sqrt(2)*V\n", "a=30.0\n", "E=150.0\n", "B=180-math.degrees(math.asin(E/V_mp))\n", "I_o=(3/(2*math.pi*R))*(V_mp*(math.cos(math.radians(a+30))-math.cos(math.radians(B)))-E*((B-a-30)*math.pi/180))\n", "\n", "#Results\n", "print(\"avg current flowing=%.2f A\" %I_o)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "avg current flowing=19.96 A\n" ] } ], "prompt_number": 31 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.37, Page No 366" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "a=30.0\n", "V=230.0\n", "\n", "#Calculations\n", "V_m=math.sqrt(2)*V\n", "V_o=V_m*(1+math.cos(math.radians(a)))/math.pi \n", "E=100\n", "R=10\n", "I_o=(V_o-E)/R \n", "I_TA=I_o*math.pi/(2*math.pi) \n", "I_Tr=math.sqrt(I_o**2*math.pi/(2*math.pi)) \n", "I_s=math.sqrt(I_o**2*(1-a/180)*math.pi/(math.pi))\n", "I_or=I_o\n", "P=E*I_o+I_or**2*R\n", "pf=(P/(V*I_s)) \n", "f=50\n", "w=2*math.pi*f\n", "t_c=(1-a/180)*math.pi/w \n", "\n", "#Results\n", "print(\"\\navg o/p current=%.2f A\" %I_o)\n", "print(\"avg o/p voltage=%.3f V\" %V_o)\n", "print(\"avg value of thyristor current=%.2f A\" %I_TA)\n", "print(\"rms value of thyristor current=%.3f A\" %I_Tr)\n", "print(\"avg value of diode current=%.2f A\" %I_TA)\n", "print(\"rms value of diode current=%.3f A\" %I_Tr)\n", "print(\"pf=%.4f\" %pf)\n", "print(\"circuit turn off time=%.2f ms\" %(t_c*1000))" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "\n", "avg o/p current=9.32 A\n", "avg o/p voltage=193.202 V\n", "avg value of thyristor current=4.66 A\n", "rms value of thyristor current=6.590 A\n", "avg value of diode current=4.66 A\n", "rms value of diode current=6.590 A\n", "pf=0.9202\n", "circuit turn off time=8.33 ms\n" ] } ], "prompt_number": 32 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.38, Page No 368" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "V=230.0\n", "V_m=math.sqrt(2)*V\n", "L=0.05\n", "f=50.0\n", "\n", "#Calculations\n", "w=2*math.pi*f\n", "a=30\n", "i_cp=2*V_m*(1-math.cos(math.radians(a)))/(w*L) \n", "R=30.0\n", "i_l=V_m/R\n", "i1=i_cp+i_l \n", "i2=i_cp \n", "\n", "#Results\n", "print(\"peak value of circulating current=%.3f A\" %i_cp)\n", "print(\"peak value of current in convertor 1=%.3f A\" %i1)\n", "print(\"peak value of current in convertor 2=%.3f A\" %i2)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "peak value of circulating current=5.548 A\n", "peak value of current in convertor 1=16.391 A\n", "peak value of current in convertor 2=5.548 A\n" ] } ], "prompt_number": 33 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 6.39, Page No 370" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "f=50.0\n", "w=2*math.pi*f\n", "R=5.0\n", "L=0.05\n", "\n", "#Calculations\n", "phi=math.degrees(math.atan(w*L/R)) \n", "phi=90+math.degrees(math.atan(w*L/R)) \n", "\n", "#Results\n", "print(\"for no current transients\")\n", "print(\"triggering angle=%.2f deg\" %phi)\n", "print(\"for worst transients\")\n", "print(\"triggering angle=%.2f deg\" %phi)" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "for no current transients\n", "triggering angle=162.34 deg\n", "for worst transients\n", "triggering angle=162.34 deg\n" ] } ], "prompt_number": 34 } ], "metadata": {} } ] }