6 files changed, 116 insertions, 0 deletions
diff --git a/3784/CH3/EX3.1/Ex3_1.sce b/3784/CH3/EX3.1/Ex3_1.sce
new file mode 100644
index 000000000..b372f1a54
--- /dev/null
+++ b/3784/CH3/EX3.1/Ex3_1.sce
@@ -0,0 +1,27 @@
+clc
+//variable initialization
+Vm= 220 //armature voltage in volts
+N= 1000 //speed in rpm
+N1= 900 // speed in rpm
+Ia= 60 //armature current in ampere
+Ra= 0.6 //armature resistance in ohm
+a= 0
+V= 165 //line voltage in volts
+
+//solution
+Eb1= Vm-Ia*Ra //back emf in volts
+Eb2= (N1/N)*Eb1 //back emf in volts
+Ea=Eb2+(Ia*Ra) //armature voltage in volts
+Em= V*sqrt(2) 
+A=(((Ea*%pi)/(3*Em)))
+a1=acosd(A)
+a2=180-a1
+Ea1=V-(Ia*Ra) //armature voltage in volts
+cosa1=((Ea/Em)*(%pi/3))
+a11=acosd((Ea1*%pi)/(3*Em))
+a22=180-a1
+printf('\n\n Firing Angle for motoring operations at rated motor torqu and 900 or -900 rpm=%0.1f \n\n',a1)
+printf('\n\n Firing Angle for motoring operations at rated motor torqu and 900 or -900 rpm=%0.1f \n\n',a2)
+printf('\n\n Firing Angle for braking operations at rated motor torqu and 900 or -900 rpm=%0.1f \n\n',a11)
+printf('\n\n Firing Angle for braking operations at rated motor torqu and 900 or -900 rpm=%0.1f \n\n',a22)
+//The answers vary due to round off error
diff --git a/3784/CH3/EX3.2/Ex3_2.sce b/3784/CH3/EX3.2/Ex3_2.sce
new file mode 100644
index 000000000..496b84a37
--- /dev/null
+++ b/3784/CH3/EX3.2/Ex3_2.sce
@@ -0,0 +1,21 @@
+clc 
+// Variable Initiallization
+Vm=220 //armature voltage in volts 
+f=50 //frequency in Hz
+Ra=10 //armature resistance in ohm
+Lr=50e-3 //circulating inductance in mH
+a1=30
+a2=150
+
+//solution
+w=2*%pi*f
+Em=sqrt(2)*220 //voltage in volts
+cosa1=cosd(a1)
+cosa2=cosd(a2)
+Irmax1=((2*Em)/(w*Lr))*(1-cosa1)
+Irmax2=((2*Em)/(w*Lr))*(1-cosa2)
+Ip=(Em/Ra)
+I1=Ip+Irmax1
+I2=Ip+Irmax2
+printf('\n\n Peak Current of Converter 1=%0.1f Amp\n\n',I1)
+printf('\n\n Peak Current of Converter 2=%0.1f Amp\n\n',I2)
diff --git a/3784/CH3/EX3.3/Ex3_3.sce b/3784/CH3/EX3.3/Ex3_3.sce
new file mode 100644
index 000000000..c05d25941
--- /dev/null
+++ b/3784/CH3/EX3.3/Ex3_3.sce
@@ -0,0 +1,15 @@
+
+clc
+// Variable initialization
+F=50 //Supply Frequency In Hz
+Vm=400 //Supply Voltage In Volts
+Ip=20 //Peak Circulating Current In Ampere
+A=60 //firing angle
+
+// solution
+Ea=Vm/(sqrt(3))
+W=2*%pi*F
+Lr=[(3*sqrt(2)*Ea)/(W*Ip)]*(1-sind(A))
+Lr1=Lr*1000//Inductance in mH
+printf('\n\n Inductance Value Needed=%0.1f mH\n\n',Lr1)
+//The answer vary due to round off error
diff --git a/3784/CH3/EX3.4/Ex3_4.sce b/3784/CH3/EX3.4/Ex3_4.sce
new file mode 100644
index 000000000..0f1194964
--- /dev/null
+++ b/3784/CH3/EX3.4/Ex3_4.sce
@@ -0,0 +1,15 @@
+clc
+// Variable Initiallization
+F=50 //Supply Frequency In Hz
+Erms=230 //RMS Voltage Per Phase In Volts
+L=0.015 //Inductance In Henry
+A1=60 //Firing Angle
+A2=120 //Firing Angle
+
+
+
+
+//solution
+W=2*%pi*F
+Icp=((3*sqrt(2)*Erms)/(W*L))*(1-sind(A1))
+printf('\n\n The Peak value of Circulating Current=%0.1f Amp\n\n',Icp)
diff --git a/3784/CH3/EX3.5/Ex3_5.sce b/3784/CH3/EX3.5/Ex3_5.sce
new file mode 100644
index 000000000..16089b0da
--- /dev/null
+++ b/3784/CH3/EX3.5/Ex3_5.sce
@@ -0,0 +1,15 @@
+clc
+// Variable Initiallization
+Vm=400 //Supply Voltage In Volt
+Ea1= 220// Voltage Of Motor In Volt
+Ia=200 //Line Current In Ampere
+Ra=0.05 //Armature Resistance In Ohm
+N1=750 //Speed Of Motor In rpm
+N2=600 //Speed Of Motor In rpm
+
+//solution
+Eb1=Ea1-(Ia*Ra)
+Eb2=(N2/N1)*Eb1
+Ea2=Eb2+(Ia*Ra)
+A=acosd((Ea2*%pi)/(Vm*3*sqrt(2)))
+printf('\n\n The Firing Angle of Rectifier=%0.1f\n\n',A)
diff --git a/3784/CH3/EX3.6/Ex3_6.sce b/3784/CH3/EX3.6/Ex3_6.sce
new file mode 100644
index 000000000..59935f183
--- /dev/null
+++ b/3784/CH3/EX3.6/Ex3_6.sce
@@ -0,0 +1,23 @@
+clc
+// Variable Initiallization
+Ea=400 // Voltage Of MOtor In Volt
+Ia1=70 //Line Current In Ampere
+Ia2=90 //Line Current In Ampere
+Ra=0.3 //Armature Resistance In Ohm
+N1=750 //Speed Of Motor In rpm
+N2=300 //Speed Of Motor In rpm
+
+//Solution
+Eb1=Ea-(Ia1*Ra)
+Eb2=(N2/N1)*Eb1
+Rb=-((Eb2-Ea-Ia2*Ra)/Ia2)//Wrongly calculated in book,wrong value of Eb2 is taken
+W1=(2*%pi*N1)/60
+Kt1=Eb1/W1
+T1=Kt1*Ia1
+W2=(2*%pi*N2)/60
+Kt2=Eb2/W2//Wrongly computed in textbook
+T2=Kt2*Ia2//The answer provided in the textbook is wrong
+printf('\n\n External resistance to be added=%0.1f ohm\n\n',Rb)
+printf('\n\n Initial braking torque=%0.1f N-m\n\n',T1)
+printf('\n\n braking torque at 300 rpm=%0.1f N-m\n\n',T2)
+//The answer provided in the textbook is wrong(both)