{
"metadata": {
"name": ""
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"CHAPTER 15 Thyristors"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-1, Page 521"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"VB=10 #breakover voltage(V)\n",
"Vin=15 #input voltage(V)\n",
"R=100.0 #resistance (Ohm)\n",
"\n",
"I1=1000*Vin/R #diode current ideally(mA)\n",
"I2=1000*(Vin-0.7)/R #diode current with second approx.(mA)\n",
"I3=1000*(Vin-0.9)/R #diode current more accurately(mA)\n",
"\n",
"print 'Diode current ideally ID1 = ',I1,'mA'\n",
"print 'Diode current with second approx. ID2 = ',I2,'mA'\n",
"print 'Diode current more accurately ID3 = ',I3,'mA'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Diode current ideally ID1 = 150.0 mA\n",
"Diode current with second approx. ID2 = 143.0 mA\n",
"Diode current more accurately ID3 = 141.0 mA\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-2, Page 525"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"Ih=4*10**-3 #holding current(mA)\n",
"R=100.0 #resistance (Ohm)\n",
"Vs=15 #input voltage (V)\n",
"\n",
"Vin=0.7+(Ih*R) #new input voltage(V)\n",
"\n",
"print 'New input voltage Vin = ',Vin,'V'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"New input voltage Vin = 1.1 V\n"
]
}
],
"prompt_number": 7
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-3, Page 525"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"R=2.0*10**3 #resistance (Ohm)\n",
"C=0.02*10**-6 #capacitance (F)\n",
"VB=10 #breakdown voltage(V)\n",
"\n",
"RC=R*C #Time constant(s)\n",
"T=0.2*RC #period (s)\n",
"f=T**-1 #frequency(Hz) \n",
"\n",
"print 'time constant RC = ',RC*10**6,'us'\n",
"print 'Period T = ',T*10**6,'us'\n",
"print 'Frequency = ',f/1000,'KHz'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"time constant RC = 40.0 us\n",
"Period T = 8.0 us\n",
"Frequency = 125.0 KHz\n"
]
}
],
"prompt_number": 9
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-4, Page 531"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"It=7*10**-3 #trigger current(mA)\n",
"R1=100.0 #resistance (Ohm)\n",
"R2=1*10**3 #resistance (Ohm)\n",
"Vt=0.75 #trigger voltage (V)\n",
"Ih=6*10**-3 #holding current(mA)\n",
"\n",
"Vin=Vt+(It*R2) #minimum input voltage(V)\n",
"VCC=0.7+(Ih*R1) #supply voltage for turning of SCR(V)\n",
"\n",
"print 'Minimum input voltage Vin = ',Vin,'V'\n",
"print 'supply voltage for turning of SCR VCC = ',VCC,'V'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Minimum input voltage Vin = 7.75 V\n",
"supply voltage for turning of SCR VCC = 1.3 V\n"
]
}
],
"prompt_number": 11
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-5, Page 532"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"IGT=200*10**-6 #trigger current(mA)\n",
"VGT=1 #trigger voltage(V) \n",
"R1=900.0 #resistance (Ohm)\n",
"R2=100.0 #resistance (Ohm)\n",
"C=0.2*10**-6 #capacitance (F)\n",
"Vt=0.75 #trigger voltage (V)\n",
"Ih=6*10**-3 #holding current(mA)\n",
"R=1*10**3 #Resistance (Ohm) \n",
"\n",
"RTH=R1*R2/(R1+R2) #Thevenin resistance (Ohm)\n",
"Vin=VGT+(IGT*RTH) #input voltage needed to trigger(V)\n",
"Vp=10*Vin #Output voltage at SCR firing point(V)\n",
"RC=C*(R/2) #time constant (s)\n",
"T=RC*0.2 #period (s)\n",
"f=1/T #frequency (Hz)\n",
"\n",
"print 'peak output voltage Vpeak = ',Vp,'V'\n",
"print 'time constant RC = ',RC*10**6,'us'\n",
"print 'Period T = ',T*10**6,'us'\n",
"print 'Frequency = ',f/1000,'KHz'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"peak output voltage Vpeak = 10.18 V\n",
"time constant RC = 100.0 us\n",
"Period T = 20.0 us\n",
"Frequency = 50.0 KHz\n"
]
}
],
"prompt_number": 16
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-6, Page 536"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"Vz=5.6 #breakdown voltage(V)\n",
"VGT1=0.75 #trigger voltage (V) \n",
"VGT2=1.5 #worst case maximum trigger voltage(V) \n",
"Vz2=6.16 #break down voltage with 10% tolerance (V)\n",
"\n",
"VCC1=Vz+VGT1 #supply voltage(V) \n",
"VCC2=VGT2+Vz2 #Over voltage (V)\n",
"\n",
"print 'supply voltage VCC1 = ',VCC1,'V'\n",
"print 'supply over voltage VCC2 = ',VCC2,'V'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"supply voltage VCC1 = 6.35 V\n",
"supply over voltage VCC2 = 7.66 V\n"
]
}
],
"prompt_number": 17
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-7, Page 539"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"import math # This will import math module\n",
"\n",
"C=0.1*10**-6 #capacitance (F)\n",
"f=60 #frequency (Hz)\n",
"R=26*10**3 #resistance(KOhm)\n",
"Vm=120 #input ac voltage(V)\n",
"\n",
"XC=(2*math.pi*f*C)**-1 #capacitive reactance(Ohm)\n",
"ZT=((R**2)+(XC**2))**0.5 #impedance (Ohm)\n",
"thetaz=math.atan2(-XC,R)*180/math.pi #angle (deg)\n",
"IC=Vm/ZT #Current through C(A)\n",
"VC=IC*XC #voltage across C(V)\n",
"thetac=180+thetaz #conduction angle(deg)\n",
"\n",
"print 'Capacitor reactance XC = ',round((XC/1000),2),'KOhm'\n",
"print 'impedance ZT = ',round((ZT/1000),2),'KOhm'\n",
"print 'firing angle = ',round(thetaz,2),'deg'\n",
"print 'Current through C, IC = ',round((IC*1000),2),'mA'\n",
"print 'voltage across C, VC = ',round(VC,2),'V'\n",
"print 'conduction angle = ',round(thetac,2),'deg'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Capacitor reactance XC = 26.53 KOhm\n",
"impedance ZT = 37.14 KOhm\n",
"firing angle = -45.57 deg\n",
"Current through C, IC = 3.23 mA\n",
"voltage across C, VC = 85.7 V\n",
"conduction angle = 134.43 deg\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-8, Page 546"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"C=1*10**-6 #capacitance (F)\n",
"R1=22.0 #resistance (Ohm)\n",
"R2=82*10**3 #resistance(KOhm)\n",
"Vs=75 #input voltage(V)\n",
"\n",
"I=Vs/R1 #current through 22Ohm resistor (A)\n",
"\n",
"print 'current through 22Ohm resistor I = ',round(I,2),'A'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"current through 22Ohm resistor I = 3.41 A\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 15-9, Page 547"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"Vdb=32.0 #diac break down voltage (V)\n",
"VTT=1 #triac trigger voltage(V)\n",
"\n",
"Vin=VTT+Vdb #input voltage for triggering triac\n",
"\n",
"print 'input voltage for triggering triac vin = ',Vin,'V'"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"input voltage for triggering triac vin = 33.0 V\n"
]
}
],
"prompt_number": 27
}
],
"metadata": {}
}
]
}