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diff --git a/_Power_Electronics/Chapter4_1.ipynb b/_Power_Electronics/Chapter4_1.ipynb deleted file mode 100755 index 22311574..00000000 --- a/_Power_Electronics/Chapter4_1.ipynb +++ /dev/null @@ -1,946 +0,0 @@ -{
- "metadata": {
- "name": ""
- },
- "nbformat": 3,
- "nbformat_minor": 0,
- "worksheets": [
- {
- "cells": [
- {
- "cell_type": "heading",
- "level": 1,
- "metadata": {},
- "source": [
- "Chapter 04 : Thyristors"
- ]
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.3, Page No 149"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "P=.5 #P=V_g*I_g\n",
- "s=130 #s=V_g/I_g\n",
- "\n",
- "#Calculations\n",
- "I_g=math.sqrt(P/s)\n",
- "V_g=s*I_g\n",
- "E=15\n",
- "R_s=(E-V_g)/I_g \n",
- "\n",
- "#Results\n",
- "print(\"Gate source resistance=%.2f ohm\" %R_s)\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": [
- "Gate source resistance=111.87 ohm\n"
- ]
- }
- ],
- "prompt_number": 1
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.4, Page No 149"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "\n",
- "#initialisation of variables\n",
- "\n",
- "R_s=120 #slope of load line is -120V/A. This gives gate source resistance\n",
- "print(\"gate source resistance=%.0f ohm\" %R_s)\n",
- "\n",
- "P=.4 #P=V_g*I_g\n",
- "E_s=15\n",
- "\n",
- "#Calculations\n",
- " #E_s=I_g*R_s+V_g % after solving this\n",
- " #120*I_g**2-15*I_g+0.4=0 so\n",
- "a=120 \n",
- "b=-15\n",
- "c=0.4\n",
- "D=math.sqrt((b**2)-4*a*c)\n",
- "I_g=(-b+D)/(2*a) \n",
- "V_g=P/I_g\n",
- "\n",
- "#Results\n",
- "print(\"\\ntrigger current=%.2f mA\" %(I_g*10**3)) \n",
- "print(\"\\nthen trigger voltage=%.3f V\" %V_g)\n",
- "I_g=(-b-D)/(2*a) \n",
- "V_g=P/I_g\n",
- "print(\"\\ntrigger current=%.2f mA\" %(I_g*10**3)) \n",
- "print(\"\\nthen trigger voltage=%.2f V\" %V_g)"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "gate source resistance=120 ohm\n",
- "\n",
- "trigger current=86.44 mA\n",
- "\n",
- "then trigger voltage=4.628 V\n",
- "\n",
- "trigger current=38.56 mA\n",
- "\n",
- "then trigger voltage=10.37 V\n"
- ]
- }
- ],
- "prompt_number": 2
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.5 Page No 150"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "\n",
- "#initialisation of variables\n",
- "\n",
- "#V_g=1+10*I_g\n",
- "P_gm=5 #P_gm=V_g*I_g\n",
- "#after solving % eqn becomes 10*I_g**2+I_g-5=0\n",
- "a=10.0 \n",
- "b=1.0 \n",
- "c=-5\n",
- "\n",
- "#Calculations\n",
- "I_g=(-b+math.sqrt(b**2-4*a*c))/(2*a)\n",
- "E_s=15\n",
- "#using E_s=R_s*I_g+V_g\n",
- "R_s=(E_s-1)/I_g-10 \n",
- "P_gav=.3 #W\n",
- "T=20*10**-6\n",
- "f=P_gav/(P_gm*T)\n",
- "dl=f*T\n",
- "\n",
- "#Results\n",
- "print(\"Reistance=%.3f ohm\" %R_s)\n",
- "print(\"Triggering freq=%.0f kHz\" %(f/1000))\n",
- "print(\"Tduty cycle=%.2f\" %dl)"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "Reistance=11.248 ohm\n",
- "Triggering freq=3 kHz\n",
- "Tduty cycle=0.06\n"
- ]
- }
- ],
- "prompt_number": 3
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.6, Page No 151"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "I=.1\n",
- "E=200.0\n",
- "L=0.2\n",
- "\n",
- "#Calculations\n",
- "t=I*L/E \n",
- "R=20.0\n",
- "t1=(-L/R)*math.log(1-(R*I/E)) \n",
- "L=2.0\n",
- "t2=(-L/R)*math.log(1-(R*I/E)) \n",
- "\n",
- "#Results\n",
- "print(\"in case load consists of (a)L=.2H\")\n",
- "print(\"min gate pulse width=%.0f us\" %(t*10**6))\n",
- "print(\"(b)R=20ohm in series with L=.2H\")\n",
- "print(\"min gate pulse width=%.3f us\" %(t1*10**6))\n",
- "print(\"(c)R=20ohm in series with L=2H\")\n",
- "print(\"min gate pulse width=%.2f us\" %(t2*10**6))"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "in case load consists of (a)L=.2H\n",
- "min gate pulse width=100 us\n",
- "(b)R=20ohm in series with L=.2H\n",
- "min gate pulse width=100.503 us\n",
- "(c)R=20ohm in series with L=2H\n",
- "min gate pulse width=1005.03 us\n"
- ]
- }
- ],
- "prompt_number": 4
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.9 Page No 163"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "\n",
- "#initialisation of variables\n",
- "\n",
- "def theta(th):\n",
- " I_m=1 #supposition\n",
- " I_av=(I_m/(2*math.pi))*(1+math.cos(math.radians(th)))\n",
- " I_rms=math.sqrt((I_m/(2*math.pi))*((180-th)*math.pi/360+.25*math.sin(math.radians(2*th))))\n",
- " FF=I_rms/I_av\n",
- " I_rms=35\n",
- " I_TAV=I_rms/FF\n",
- " return I_TAV\n",
- "\n",
- "#Calculations\n",
- "print(\"when conduction angle=180\")\n",
- "th=0\n",
- "I_TAV=theta(th)\n",
- "print(\"avg on current rating=%.3f A\" %I_TAV)\n",
- "print(\"when conduction angle=90\")\n",
- "th=90\n",
- "I_TAV=theta(th)\n",
- "\n",
- "#Results\n",
- "print(\"avg on current rating=%.3f A\" %I_TAV)\n",
- "print(\"when conduction angle=30\")\n",
- "th=150\n",
- "I_TAV=theta(th)\n",
- "print(\"avg on current rating=%.3f A\" %I_TAV)"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "when conduction angle=180\n",
- "avg on current rating=22.282 A\n",
- "when conduction angle=90\n",
- "avg on current rating=15.756 A\n",
- "when conduction angle=30\n",
- "avg on current rating=8.790 A\n"
- ]
- }
- ],
- "prompt_number": 5
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.10, Page No 164"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "\n",
- "def theta(th):\n",
- " n=360.0/th\n",
- " I=1.0 #supposition\n",
- " I_av=I/n\n",
- " I_rms=I/math.sqrt(n)\n",
- " FF=I_rms/I_av\n",
- " I_rms=35\n",
- " I_TAV=I_rms/FF\n",
- " return I_TAV\n",
- "\n",
- "#Calculations\n",
- "th=180.0\n",
- "I_TAV1=theta(th)\n",
- "th=90.0\n",
- "I_TAV2=theta(th)\n",
- "th=30.0\n",
- "I_TAV3=theta(th)\n",
- "\n",
- "#Results\n",
- "print(\"when conduction angle=180\")\n",
- "print(\"avg on current rating=%.3f A\" %I_TAV)\n",
- "print(\"when conduction angle=90\")\n",
- "print(\"avg on current rating=%.1f A\" %I_TAV2)\n",
- "print(\"when conduction angle=30\")\n",
- "print(\"avg on current rating=%.4f A\" %I_TAV3)\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "when conduction angle=180\n",
- "avg on current rating=8.790 A\n",
- "when conduction angle=90\n",
- "avg on current rating=17.5 A\n",
- "when conduction angle=30\n",
- "avg on current rating=10.1036 A\n"
- ]
- }
- ],
- "prompt_number": 6
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.11 Page No 165"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math \n",
- "\n",
- "#initialisation of variables\n",
- "f=50.0 #Hz\n",
- "\n",
- "#Calculations\n",
- "I_sb=3000.0\n",
- "t=1/(4*f)\n",
- "T=1/(2*f)\n",
- "I=math.sqrt(I_sb**2*t/T) \n",
- "r=(I_sb/math.sqrt(2))**2*T \n",
- "\n",
- "#Results\n",
- "print(\"surge current rating=%.2f A\" %I)\n",
- "print(\"\\nI**2*t rating=%.0f A^2.s\" %r)\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "surge current rating=2121.32 A\n",
- "\n",
- "I**2*t rating=45000 A^2.s\n"
- ]
- }
- ],
- "prompt_number": 7
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.12 Page No 165"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "\n",
- "V_s=300.0 #V\n",
- "R=60.0 #ohm\n",
- "L=2.0 #H\n",
- "\n",
- "#Calculations\n",
- "t=40*10**-6 #s\n",
- "i_T=(V_s/R)*(1-math.exp(-R*t/L))\n",
- "i=.036 #A\n",
- "R1=V_s/(i-i_T)\n",
- "\n",
- "#Results\n",
- "print(\"maximum value of remedial parameter=%.3f kilo-ohm\" %(R1/1000))\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "maximum value of remedial parameter=9.999 kilo-ohm\n"
- ]
- }
- ],
- "prompt_number": 8
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.16 Page No 172"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "\n",
- "#initialisation of variables\n",
- "V_p=230.0*math.sqrt(2)\n",
- "\n",
- "#Calculations\n",
- "R=1+((1)**-1+(10)**-1)**-1\n",
- "A=V_p/R\n",
- "s=1 #s\n",
- "t_c=20*A**-2*s\n",
- "\n",
- "#Results\n",
- "print(\"fault clearance time=%.4f ms\" %(t_c*10**3))\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "fault clearance time=0.6890 ms\n"
- ]
- }
- ],
- "prompt_number": 9
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.17, Page No 176"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "\n",
- "#initialisation of variables\n",
- "\n",
- "V_s=math.sqrt(2)*230 #V\n",
- "L=15*10**-6 #H\n",
- "I=V_s/L #I=(di/dt)_max\n",
- "R_s=10 #ohm\n",
- "v=I*R_s #v=(dv/dt)_max\n",
- "\n",
- "#Calculations\n",
- "f=50 #Hz\n",
- "X_L=L*2*math.pi*f\n",
- "R=2\n",
- "I_max=V_s/(R+X_L) \n",
- "FF=math.pi/math.sqrt(2)\n",
- "I_TAV1=I_max/FF \n",
- "FF=3.98184\n",
- "I_TAV2=I_max/FF \n",
- "\n",
- "\n",
- "#RESULTS\n",
- "print(\"(di/dt)_max=%.3f A/usec\" %(I/10**6))\n",
- "print(\"\\n(dv/dt)_max=%.2f V/usec\" %(v/10**6))\n",
- "print(\"\\nI_rms=%.3f A\" %I_max)\n",
- "print(\"when conduction angle=90\")\n",
- "print(\"I_TAV=%.3f A\" %I_TAV1)\n",
- "print(\"when conduction angle=30\")\n",
- "print(\"I_TAV=%.3f A\" %I_TAV2)\n",
- "print(\"\\nvoltage rating=%.3f V\" %(2.75*V_s)) #rating is taken 2.75 times of peak working voltage unlike 2.5 to 3 times as mentioned int book."
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "(di/dt)_max=21.685 A/usec\n",
- "\n",
- "(dv/dt)_max=216.85 V/usec\n",
- "\n",
- "I_rms=162.252 A\n",
- "when conduction angle=90\n",
- "I_TAV=73.039 A\n",
- "when conduction angle=30\n",
- "I_TAV=40.748 A\n",
- "\n",
- "voltage rating=894.490 V\n"
- ]
- }
- ],
- "prompt_number": 10
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.19, Page No 186"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "\n",
- "T_jm=125\n",
- "th_jc=.15 #degC/W\n",
- "th_cs=0.075 #degC/W\n",
- "\n",
- "\n",
- "#Calculations\n",
- "dT=54 #dT=T_s-T_a\n",
- "P_av=120\n",
- "th_sa=dT/P_av\n",
- "T_a=40 #ambient temp\n",
- "P_av=(T_jm-T_a)/(th_sa+th_jc+th_cs)\n",
- "if (P_av-120)<1 :\n",
- " print(\"selection of heat sink is satisfactory\")\n",
- "\n",
- "dT=58 #dT=T_s-T_a\n",
- "P_av=120\n",
- "th_sa=dT/P_av\n",
- "T_a=40 #ambient temp\n",
- "P_av=(T_jm-T_a)/(th_sa+th_jc+th_cs)\n",
- "if (P_av-120)<1 :\n",
- " print(\"selection of heat sink is satisfactory\")\n",
- "\n",
- "V_m=math.sqrt(2)*230\n",
- "R=2\n",
- "I_TAV=V_m/(R*math.pi)\n",
- "P_av=90\n",
- "th_sa=(T_jm-T_a)/P_av-(th_jc+th_cs)\n",
- "dT=P_av*th_sa\n",
- "print(\"for heat sink\") \n",
- "print(\"T_s-T_a=%.2f degC\" %dT) \n",
- "print(\"\\nP_av=%.0f W\" %P_av)\n",
- "P=(V_m/2)**2/R\n",
- "eff=P/(P+P_av) \n",
- "print(\"\\nckt efficiency=%.3f pu\" %eff)\n",
- "a=60 #delay angle\n",
- "I_TAV=(V_m/(2*math.pi*R))*(1+math.cos(math.radians(a)))\n",
- "print(\"\\nI_TAV=%.2f A\" %I_TAV)\n",
- "dT=46\n",
- "T_s=dT+T_a\n",
- "T_c=T_s+P_av*th_cs \n",
- "T_j=T_c+P_av*th_jc \n",
- "\n",
- "#Results\n",
- "print(\"\\ncase temp=%.2f degC\" %T_c)\n",
- "print(\"\\njunction temp=%.2f degC\" %T_j)\n",
- "\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "for heat sink\n",
- "T_s-T_a=-20.25 degC\n",
- "\n",
- "P_av=90 W\n",
- "\n",
- "ckt efficiency=0.993 pu\n",
- "\n",
- "I_TAV=38.83 A\n",
- "\n",
- "case temp=92.75 degC\n",
- "\n",
- "junction temp=106.25 degC\n"
- ]
- }
- ],
- "prompt_number": 11
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.20, Page No 187"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "T_j=125.0 #degC\n",
- "T_s=70.0 #degC\n",
- "th_jc=.16 #degC/W\n",
- "th_cs=.08 #degC/W\n",
- "\n",
- "#Calculations\n",
- "P_av1=(T_j-T_s)/(th_jc+th_cs) \n",
- "\n",
- "T_s=60 #degC\n",
- "P_av2=(T_j-T_s)/(th_jc+th_cs) \n",
- "inc=(math.sqrt(P_av2)-math.sqrt(P_av1))*100/math.sqrt(P_av1) \n",
- "\n",
- "#Results\n",
- "print(\"Total avg power loss in thristor sink combination=%.2f W\" %P_av1)\n",
- "print(\"Percentage inc in rating=%.2f\" %inc)"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "Total avg power loss in thristor sink combination=229.17 W\n",
- "Percentage inc in rating=8.71\n"
- ]
- }
- ],
- "prompt_number": 12
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.21, Page No 197"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "\n",
- "R=25000.0\n",
- "I_l1=.021 #I_l=leakage current\n",
- "I_l2=.025\n",
- "I_l3=.018\n",
- "I_l4=.016\n",
- " #V1=(I-I_l1)*R\n",
- " #V2=(I-I_l2)*R\n",
- " #V3=(I-I_l3)*R\n",
- " #V4=(I-I_l4)*R\n",
- " #V=V1+V2+V3+V4\n",
- " \n",
- "#Calculations\n",
- "V=10000.0\n",
- "I_l=I_l1+I_l2+I_l3+I_l4\n",
- " #after solving\n",
- "I=((V/R)+I_l)/4\n",
- "R_c=40.0\n",
- "V1=(I-I_l1)*R \n",
- "\n",
- "#Resluts\n",
- "print(\"voltage across SCR1=%.0f V\" %V1)\n",
- "V2=(I-I_l2)*R \n",
- "print(\"\\nvoltage across SCR2=%.0f V\" %V2)\n",
- "V3=(I-I_l3)*R \n",
- "print(\"\\nvoltage across SCR3=%.0f V\" %V3)\n",
- "V4=(I-I_l4)*R \n",
- "print(\"\\nvoltage across SCR4=%.0f V\" %V4)\n",
- "\n",
- "I1=V1/R_c \n",
- "print(\"\\ndischarge current through SCR1=%.3f A\" %I1)\n",
- "I2=V2/R_c \n",
- "print(\"\\ndischarge current through SCR2=%.3f A\" %I2)\n",
- "I3=V3/R_c \n",
- "print(\"\\ndischarge current through SCR3=%.3f A\" %I3)\n",
- "I4=V4/R_c \n",
- "print(\"\\ndischarge current through SCR4=%.3f A\" %I4)\n",
- "\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "voltage across SCR1=2475 V\n",
- "\n",
- "voltage across SCR2=2375 V\n",
- "\n",
- "voltage across SCR3=2550 V\n",
- "\n",
- "voltage across SCR4=2600 V\n",
- "\n",
- "discharge current through SCR1=61.875 A\n",
- "\n",
- "discharge current through SCR2=59.375 A\n",
- "\n",
- "discharge current through SCR3=63.750 A\n",
- "\n",
- "discharge current through SCR4=65.000 A\n"
- ]
- }
- ],
- "prompt_number": 13
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.22, Page No 198"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "V_r=1000 #rating of SCR\n",
- "I_r=200 #rating of SCR\n",
- "V_s=6000 #rating of String\n",
- "I_s=1000 #rating of String\n",
- "\n",
- "#Calculations\n",
- "print(\"when DRF=.1\")\n",
- "DRF=.1\n",
- "n_s=V_s/(V_r*(1-DRF)) \n",
- "print(\"number of series units=%.0f\" %math.ceil(n_s))\n",
- "n_p=I_s/(I_r*(1-DRF)) \n",
- "print(\"\\nnumber of parrallel units=%.0f\" %math.ceil(n_p))\n",
- "print(\"when DRF=.2\")\n",
- "DRF=.2\n",
- "\n",
- "#Results\n",
- "n_s=V_s/(V_r*(1-DRF)) \n",
- "print(\"number of series units=%.0f\" %math.ceil(n_s))\n",
- "n_p=I_s/(I_r*(1-DRF)) \n",
- "print(\"\\nnumber of parrallel units=%.0f\" %math.ceil(n_p))"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "when DRF=.1\n",
- "number of series units=7\n",
- "\n",
- "number of parrallel units=6\n",
- "when DRF=.2\n",
- "number of series units=8\n",
- "\n",
- "number of parrallel units=7\n"
- ]
- }
- ],
- "prompt_number": 14
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.23, Page No 198"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "V1=1.6 #on state voltage drop of SCR1\n",
- "V2=1.2 #on state voltage drop of SCR2\n",
- "I1=250.0 #current rating of SCR1\n",
- "I2=350.0 #current rating of SCR2\n",
- "\n",
- "#Calculations\n",
- "R1=V1/I1\n",
- "R2=V2/I2\n",
- "I=600.0 #current to be shared\n",
- " #for SCR1 % I*(R1+R)/(total resistance)=k*I1 (1)\n",
- " #for SCR2 % I*(R2+R)/(total resistance)=k*I2 (2)\n",
- " #(1)/(2)\n",
- "R=(R2*I2-R1*I1)/(I1-I2)\n",
- "\n",
- "\n",
- "#Results\n",
- "print(\"RSequired value of resistance=%.3f ohm\" %R)"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "RSequired value of resistance=0.004 ohm\n"
- ]
- }
- ],
- "prompt_number": 15
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.25, Page No 223"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "f=2000.0 #Hz\n",
- "C=0.04*10**-6\n",
- "n=.72\n",
- "\n",
- "#Calculations\n",
- "R=1/(f*C*math.log(1/(1-n))) \n",
- "V_p=18\n",
- "V_BB=V_p/n\n",
- "R2=10**4/(n*V_BB) \n",
- "I=4.2*10**-3 #leakage current\n",
- "R_BB=5000\n",
- "R1=(V_BB/I)-R2-R_BB\n",
- "\n",
- "#Results\n",
- "print(\"R=%.2f kilo-ohm\" %(R/1000))\n",
- "print(\"\\nR2=%.2f ohm\" %R2)\n",
- "print(\"\\nR1=%.0f ohm\" %R1)\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "R=9.82 kilo-ohm\n",
- "\n",
- "R2=555.56 ohm\n",
- "\n",
- "R1=397 ohm\n"
- ]
- }
- ],
- "prompt_number": 16
- },
- {
- "cell_type": "heading",
- "level": 2,
- "metadata": {},
- "source": [
- "Example 4.26, Page No 223"
- ]
- },
- {
- "cell_type": "code",
- "collapsed": false,
- "input": [
- "import math\n",
- "#initialisation of variables\n",
- "\n",
- "V_p=18.0\n",
- "n=.72\n",
- "V_BB=V_p/n\n",
- "I_p=.6*10**-3\n",
- "I_v=2.5*10**-3\n",
- "V_v=1\n",
- "\n",
- "#Calculations\n",
- "R_max=V_BB*(1-n)/I_p \n",
- "print(\"R_max=%.2f kilo-ohm\" %(R_max/1000))\n",
- "R_min=(V_BB-V_v)/I_v \n",
- "print(\"\\nR_min=%.2f kilo-ohm\" %(R_min/1000))\n",
- "\n",
- "C=.04*10**-6\n",
- "f_min=1/(R_max*C*math.log(1/(1-n))) \n",
- "print(\"\\nf_min=%.3f kHz\" %(f_min/1000))\n",
- "f_max=1/(R_min*C*math.log(1/(1-n))) \n",
- "print(\"\\nf_max=%.2f kHz\" %(f_max/1000))\n"
- ],
- "language": "python",
- "metadata": {},
- "outputs": [
- {
- "output_type": "stream",
- "stream": "stdout",
- "text": [
- "R_max=11.67 kilo-ohm\n",
- "\n",
- "R_min=9.60 kilo-ohm\n",
- "\n",
- "f_min=1.683 kHz\n",
- "\n",
- "f_max=2.05 kHz\n"
- ]
- }
- ],
- "prompt_number": 17
- }
- ],
- "metadata": {}
- }
- ]
-}
\ No newline at end of file |