initial commit / add all books

44 files changed, 698 insertions, 0 deletions

diff --git a/1938/CH5/EX5.1/5_1.sce b/1938/CH5/EX5.1/5_1.sce
new file mode 100755
index 000000000..a459d7864
--- /dev/null
+++ b/1938/CH5/EX5.1/5_1.sce
@@ -0,0 +1,18 @@
+clc,clear

+printf('Example 5.1\n\n')

+

+P=1000*10^3 //load power

+phi=acosd(0.8) //power factor lagging angle

+V_L=11*10^3 //rated terminal voltae

+R_a=0.4 //armature resistance per phase

+X_s=3//synchronous reactance per phase

+

+I_L=P/(sqrt(3)*V_L*cosd(phi))

+I_aph=I_L //for star connected load

+I_a=I_L//current through armature

+V_ph=V_L/sqrt(3) //rated terminal volatge phase value

+

+E_ph= sqrt(  (V_ph*cosd(phi)+I_a*R_a)^2+(V_ph*sind(phi)+I_a*X_s)^2   )  //emf generated phase value

+E_line=E_ph*sqrt(3) //line value of emf generated

+regulation=100*(E_ph-V_ph)/V_ph  //pecentage regulation

+printf('Line value of e.m.f generated is %.2f kV\nRegulation is %.3f percent',E_line*10^-3,regulation)

diff --git a/1938/CH5/EX5.10/5_10.jpg b/1938/CH5/EX5.10/5_10.jpg
new file mode 100755
index 000000000..4dcf3b32e
--- /dev/null
+++ b/1938/CH5/EX5.10/5_10.jpg
diff --git a/1938/CH5/EX5.10/5_10.sce b/1938/CH5/EX5.10/5_10.sce
new file mode 100755
index 000000000..dda1cb11e
--- /dev/null
+++ b/1938/CH5/EX5.10/5_10.sce
@@ -0,0 +1,19 @@
+clc,clear

+printf('Example 5.10\n\n')

+

+VA=125*10^3

+V_L=400,V_ph=V_L/sqrt(3)

+I_L=VA/(sqrt(3)*V_L)

+I_aph=I_L

+

+I_f=4,I_asc=I_aph/2 //for half load.. refer to graph

+V_OC_line=140

+V_OC_ph=V_OC_line/sqrt(3)

+I_asc_ph=I_asc

+Z_s= V_OC_ph/I_asc_ph

+R_a=0.1,X_s=sqrt(Z_s^2-R_a^2) //armature resistance and synchronous reactance

+

+phi=acos(0.8)

+E_ph = sqrt((V_ph*cos(phi)+I_asc*R_a)^2 +(V_ph*sin(phi)- I_asc*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Voltage regulation at 0.8 pf leading for half load is %.2f percent\n',regulation)

diff --git a/1938/CH5/EX5.11/5_11.sce b/1938/CH5/EX5.11/5_11.sce
new file mode 100755
index 000000000..9d92af7cc
--- /dev/null
+++ b/1938/CH5/EX5.11/5_11.sce
@@ -0,0 +1,25 @@
+clc,clear

+printf('Example 5.11\n\n')

+

+V_OC_line=575,   V_OC_ph=V_OC_line/sqrt(3)

+I_asc_line=75

+I_asc_ph  =I_asc_line 

+I_aph=I_asc_ph

+I_L=I_aph

+

+Z_s= V_OC_ph/I_asc_ph

+R_a=2.16/2

+X_s =  sqrt(Z_s^2 - R_a^2)

+

+//on full load

+E_ph=6100

+phi=acos(0.8) //leading

+

+//using E_ph = sqrt((V_ph*cos(phi)+I_a*R_a)^2 +(V_ph*sin(phi)- I_a*X_s)^2)

+p=[1 -256.68 -3.71*10^7]

+roots(p)

+V_ph=ans(1) //second root is ignored as its -ve

+V_L=V_ph*sqrt(3)

+printf('Rated terminal voltage between the lines is %.3f V \n',V_L)

+VA_rating=sqrt(3)*V_L*I_L

+printf('kVA rating of the alternator is %.2f kVA',VA_rating*10^-3)

diff --git a/1938/CH5/EX5.12/5_12.sce b/1938/CH5/EX5.12/5_12.sce
new file mode 100755
index 000000000..9bca5aafb
--- /dev/null
+++ b/1938/CH5/EX5.12/5_12.sce
@@ -0,0 +1,20 @@
+clc,clear

+printf('Example 5.12\n\n')

+

+V_L=6600, V_ph=V_L/sqrt(3)

+VA=1500*10^3

+I_L=VA/(sqrt(3)*V_L)

+I_aph=I_L

+

+R_a=0.5, X_s=5//armature resistance and synchronous reactance

+phi=acos(0.8)

+E_ph = sqrt((V_ph*cos(phi)+I_aph*R_a)^2 +(V_ph*sin(phi)+ I_aph*X_s)^2)

+printf('Induced EMF per phase is %f V\n',E_ph)

+

+//full load 

+phi=acos(1)

+//using E_ph = sqrt((V_ph*cos(phi)+I_a*R_a)^2 +(V_ph*sin(phi)- I_a*X_s)^2)

+p=[1 131.215 -1.791*10^7]

+roots(p)

+V_ph=ans(2) //first root is ignored as it is -ve

+printf('Terminal voltage per phase is %f V',V_ph)

diff --git a/1938/CH5/EX5.13/5_13.sce b/1938/CH5/EX5.13/5_13.sce
new file mode 100755
index 000000000..183fe4cff
--- /dev/null
+++ b/1938/CH5/EX5.13/5_13.sce
@@ -0,0 +1,29 @@
+clc,clear

+printf('Example 5.13\n\n')

+

+V_ph=2000

+R_a=0.8

+I_sc=100

+V_OC=500

+I_f=2.5

+Z_s=V_OC/I_sc

+X_s= sqrt(Z_s^2 - R_a^2 )

+I_aFL=100,I_a=I_aFL

+

+//part(i)

+phi=acos(1)

+E_ph = sqrt((V_ph*cos(phi)+I_a*R_a)^2 +(V_ph*sin(phi)+ I_a*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+printf('(i)Voltage regulation is %.2f percent\n',regulation)

+

+//part(ii)

+phi2=acos(0.8)

+E_ph2 = sqrt((V_ph*cos(phi2)+I_a*R_a)^2 +(V_ph*sin(phi2)- I_a*X_s)^2)

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf('(ii)Voltage regulation is %.2f percent\n',regulation2)

+

+//part(iii)

+phi3=acos(0.71)

+E_ph3 = sqrt((V_ph*cos(phi3)+I_a*R_a)^2 +(V_ph*sin(phi3)+ I_a*X_s)^2)

+regulation3=100*(E_ph3-V_ph)/V_ph

+printf('(iii)Voltage regulation is %.2f percent\n',regulation3)

diff --git a/1938/CH5/EX5.14/5_14.sce b/1938/CH5/EX5.14/5_14.sce
new file mode 100755
index 000000000..7a2dbc0e0
--- /dev/null
+++ b/1938/CH5/EX5.14/5_14.sce
@@ -0,0 +1,19 @@
+clc,clear

+printf('Example 5.14\n\n')

+

+VA=1000*1000

+V_L=4600 , V_ph=V_L/sqrt(3)

+I_L=VA/(sqrt(3)*V_L)

+I_aph_FL=I_L,I_aph=I_aph_FL

+I_sc=(150/100)* I_aph_FL

+V_OC_line=1744

+V_OC_ph= V_OC_line/sqrt(3)

+

+Z_s=V_OC_ph / I_sc

+R_a=1

+X_s=sqrt(Z_s^2-R_a^2)

+

+phi=acos(0.8 ) //lagging

+E_ph = sqrt((V_ph*cos(phi)+I_aph*R_a)^2 +(V_ph*sin(phi)+ I_aph*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Voltage regulation at full load 0.8 pf is %.2f percent\n',regulation)

diff --git a/1938/CH5/EX5.15/5_15.sce b/1938/CH5/EX5.15/5_15.sce
new file mode 100755
index 000000000..eacf2505d
--- /dev/null
+++ b/1938/CH5/EX5.15/5_15.sce
@@ -0,0 +1,41 @@
+clc,clear

+printf('Example 5.15\n\n')

+

+//part(i)    Ampere turn method

+F_O=37.5

+F_AR=20

+V_L=6600, V_ph=V_L/sqrt(3)

+

+//lagging

+phi=acos(0.8) 

+F_R= sqrt((F_O+F_AR*sin(phi) )^2 + (F_AR*cos(phi))^2 ) 

+//E_ph corresponding to F_R can be obtained by plotting open circuit characteristics

+E_ph=4350

+regulation=100*(E_ph-V_ph)/V_ph

+printf('(i)By Ampere-turn method or MMF method\nFull-load regulation at 0.8 lagging pf is %.2f percent\n',regulation)

+//leading

+phi=acos(0.8) 

+F_R= sqrt((F_O-F_AR*sin(phi) )^2 + (F_AR*cos(phi))^2 ) 

+//E_ph corresponding to F_R can be obtained by plotting open circuit characteristics

+E_ph=3000

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Full-load regulation at 0.8 leading pf is %.2f percent\n',regulation)

+

+//EMF method

+V_OC_ph=100,V_ph=100

+I_sc= 100*(F_O/F_AR)   //times the rated value

+Z_s=V_OC_ph/I_sc

+F_O= 100

+F_AR= Z_s*100

+

+//lagging

+phi=acos(0.8)

+F_R=  sqrt((F_O+F_AR*sin(phi) )^2 + (F_AR*cos(phi))^2 ) 

+regulation=100*(F_R-V_ph)/V_ph

+printf('\n(ii)Synchronous impedance method or EMF method\n')

+printf('Full-load regulation at 0.8 lagging pf is %.2f percent\n',regulation)

+//leading

+phi=acos(0.8)

+F_R=  sqrt((F_O-F_AR*sin(phi) )^2 + (F_AR*cos(phi))^2 ) 

+regulation=100*(F_R-V_ph)/V_ph

+printf('Full-load regulation at 0.8 leading pf is %.2f percent\n',regulation)

diff --git a/1938/CH5/EX5.15/5_15_1.jpg b/1938/CH5/EX5.15/5_15_1.jpg
new file mode 100755
index 000000000..794da69ba
--- /dev/null
+++ b/1938/CH5/EX5.15/5_15_1.jpg
diff --git a/1938/CH5/EX5.15/5_15_2.jpg b/1938/CH5/EX5.15/5_15_2.jpg
new file mode 100755
index 000000000..dedc2df98
--- /dev/null
+++ b/1938/CH5/EX5.15/5_15_2.jpg
diff --git a/1938/CH5/EX5.16/5_16.sce b/1938/CH5/EX5.16/5_16.sce
new file mode 100755
index 000000000..2d96c13fe
--- /dev/null
+++ b/1938/CH5/EX5.16/5_16.sce
@@ -0,0 +1,13 @@
+clc,clear

+printf('Example 5.16\n\n')

+

+V_L=6000,V_ph=V_L/sqrt(3)

+I_ph_X_Lph = 0.9*500  //leakage reactance drop in volts = 0.9 cm * 500 V/cm

+phi= acos(0.8) //lagging

+

+E_1ph=sqrt( (V_ph*cos(phi))^2 + (V_ph*sin(phi)+I_ph_X_Lph)^2 )   //From triangle OAB

+F_f1 = 26 //from OCC

+F_AR= 2.9*5  //2.9cm * 5 A/cm

+

+F_R =   sqrt(F_f1^2 + F_AR^2 -2*F_AR*F_f1*cos(phi+ (%pi/2)) )

+printf('Required field current is %.2f A',F_R)

diff --git a/1938/CH5/EX5.16/5_16_1.jpg b/1938/CH5/EX5.16/5_16_1.jpg
new file mode 100755
index 000000000..2f83bd8fc
--- /dev/null
+++ b/1938/CH5/EX5.16/5_16_1.jpg
diff --git a/1938/CH5/EX5.16/5_16_2.jpg b/1938/CH5/EX5.16/5_16_2.jpg
new file mode 100755
index 000000000..469500ff9
--- /dev/null
+++ b/1938/CH5/EX5.16/5_16_2.jpg
diff --git a/1938/CH5/EX5.17/5_17.sce b/1938/CH5/EX5.17/5_17.sce
new file mode 100755
index 000000000..6b52295be
--- /dev/null
+++ b/1938/CH5/EX5.17/5_17.sce
@@ -0,0 +1,19 @@
+clc,clear

+printf('Example 5.17\n\n')

+

+V_L=400,V_ph=V_L/sqrt(3)

+VA=40*10^3

+I_L=VA/(sqrt(3)*V_L) , I_aph=I_L

+I_aph_X_Lph = 0.65*50  //leakage reactance drop in volts = 2.4 cm * 500 V/cm

+X_Lph= I_aph_X_Lph/ I_aph

+printf('Armature leakage reactance is %.3f ohms\nNote:This answer doesnt match with textbook as it has been reciprocated in textbook\n\n',X_Lph)

+phi=acos(0.8)  //lagging

+E_ph = sqrt((V_ph*cos(phi))^2 +(V_ph*sin(phi)+ I_aph_X_Lph)^2)

+F_f1=15.6 //as obtained from OCC corresponding to this E_ph

+

+F_AR= 2.3*3  //2.3cm * 3 A/cm

+printf('Armature reaction is %.1f \n',F_AR)

+F_R =   sqrt(F_f1^2 + F_AR^2 -2*F_AR*F_f1*cos(phi+ (%pi/2)) )  //cosine rule to Triangle OAB

+E_ph=267.5  //corresponding to F_R from open circiut characteristics

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Voltage regulation at 0.8 pf lagging is %.1f percent\n',regulation)

diff --git a/1938/CH5/EX5.17/5_17_1.jpg b/1938/CH5/EX5.17/5_17_1.jpg
new file mode 100755
index 000000000..a5166d722
--- /dev/null
+++ b/1938/CH5/EX5.17/5_17_1.jpg
diff --git a/1938/CH5/EX5.17/5_17_2.jpg b/1938/CH5/EX5.17/5_17_2.jpg
new file mode 100755
index 000000000..ae5cfd58d
--- /dev/null
+++ b/1938/CH5/EX5.17/5_17_2.jpg
diff --git a/1938/CH5/EX5.18/5_18.jpg b/1938/CH5/EX5.18/5_18.jpg
new file mode 100755
index 000000000..054700da5
--- /dev/null
+++ b/1938/CH5/EX5.18/5_18.jpg
diff --git a/1938/CH5/EX5.18/5_18.sce b/1938/CH5/EX5.18/5_18.sce
new file mode 100755
index 000000000..b2b79913e
--- /dev/null
+++ b/1938/CH5/EX5.18/5_18.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 5.18\n\n')

+

+VA=10*10^3

+V_L=11*10^3,V_ph=V_L/sqrt(3)

+I_ph_X_Lph = 2.4*500  //leakage reactance drop in volts = 2.4 cm * 500 V/cm

+I_ph_R_aph =VA/(sqrt(3)*V_L)

+phi=acos(0.8)

+E_ph = sqrt((V_ph*cos(phi)+I_ph_R_aph)^2 +(V_ph*sin(phi)+ I_ph_X_Lph)^2)

+F_f1=109 //obtained from open circuit characteristics corresponding to calculated E_ph

+F_AR= 2.8*10  //2.8cm * 10 A/cm

+F_R =   sqrt(F_f1^2 + F_AR^2 -2*F_AR*F_f1*cos(phi+ (%pi/2)) )  //cosine rule to Triangle OAB

+E_ph=7700  //corresponding to F_R from open circiut characteristics

+

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Voltage regulation at full-load 0.8 pf lagging is %.2f percent\n',regulation)

diff --git a/1938/CH5/EX5.19/5_19.sce b/1938/CH5/EX5.19/5_19.sce
new file mode 100755
index 000000000..7e387899f
--- /dev/null
+++ b/1938/CH5/EX5.19/5_19.sce
@@ -0,0 +1,18 @@
+clc,clear

+printf('Example 5.19\n\n')

+

+VA=2000*1000

+V_L=11000,V_ph=V_L/sqrt(3)

+R_a=0.3,X_s=5 //armature resistance and synchronous reactance

+

+//case (i)

+phi=acos(0.8) //lagging

+I_L=VA/(sqrt(3)*V_L)  , I_a=I_L

+E_ph = sqrt((V_ph*cos(phi)+I_a*R_a)^2 +(V_ph*sin(phi)+ I_a*X_s)^2)

+

+//Using E_ph = sqrt((V_ph*cos(phi)+I_aph*R_a)^2 +(V_ph*sin(phi)+ I_aph*X_s)^2)

+//we get  V_ph^2 -579.4455 V_ph -44653301.91=0

+p=[1 -579.4455 -44653301.91]

+roots(p)

+V_ph=ans(1) //second root is ignored as its -ve

+printf('Terminal voltage is %.4f V',V_ph)

diff --git a/1938/CH5/EX5.2/5_2.sce b/1938/CH5/EX5.2/5_2.sce
new file mode 100755
index 000000000..e8917cf15
--- /dev/null
+++ b/1938/CH5/EX5.2/5_2.sce
@@ -0,0 +1,23 @@
+clc,clear

+printf('Example 5.2\n\n')

+

+VA=1200*10^3

+V_L=6600

+R_a=0.25 //armature resistance per phase

+X_s=5//synchronous reactance per phase

+

+I_L=VA/(sqrt(3)*V_L)

+I_aph=I_L //for star connected load

+I_a=I_L

+V_ph=V_L/sqrt(3)

+

+//Part(i)

+phi1=acos(0.8)//and lagging

+E_ph1= sqrt(  (V_ph*cos(phi1)+I_a*R_a)^2+(V_ph*sin(phi1)+I_a*X_s)^2   )

+regulation=100*(E_ph1-V_ph)/V_ph  //percentage regulation

+printf('(i)Regulation at 0.8 lagging pf is %.2f percent',regulation)

+//Part(ii)

+phi2=acos(0.8)//and leading

+E_ph2= sqrt(  (V_ph*cos(phi2)+I_a*R_a)^2+(V_ph*sin(phi2)-I_a*X_s)^2   )

+regulation2=100*(E_ph2-V_ph)/V_ph //percentage regulation

+printf('\n(ii)Regulation at 0.8 leading pf is %.2f percent',regulation2)

diff --git a/1938/CH5/EX5.20/5_20.jpg b/1938/CH5/EX5.20/5_20.jpg
new file mode 100755
index 000000000..a7e5b5d1e
--- /dev/null
+++ b/1938/CH5/EX5.20/5_20.jpg
diff --git a/1938/CH5/EX5.20/5_20.sce b/1938/CH5/EX5.20/5_20.sce
new file mode 100755
index 000000000..e190c4c70
--- /dev/null
+++ b/1938/CH5/EX5.20/5_20.sce
@@ -0,0 +1,30 @@
+clc,clear

+printf('Example 5.20\n\n')

+

+R_a=0.6,X_s=6 //armature resistance and synchronous reactance per phase

+E_L=6599, E_ph=E_L/sqrt(3)

+I_L=180,I_a=I_L

+

+//part(i)

+// using E_ph = sqrt((V_ph*cos(phi)+I_a*R_a)^2 +(V_ph*sin(phi)+ I_a*X_s)^2) and solving for V_ph

+p=[1 1135.83 -13338836.49]

+roots(p)

+V_ph=ans(2)

+V_L=V_ph*sqrt(3)

+regulation=100*(E_ph-V_ph)/V_ph

+

+phi=acos(0.9)

+theta=atan(      (I_a*X_s+V_ph*sin(phi) )/(E_ph)               )

+delta=theta-phi

+printf('(i)0.9 lagging\nTerminal voltage is %.2f V\nVoltage regulation is %.2f percent\nLoad angle is %.2f degrees',V_ph*sqrt(3),regulation,delta*(180/%pi))

+

+//part(ii)

+phi_2=acos(0.8)

+// using E_ph = sqrt((V_ph*cos(phi)+I_a*R_a)^2 +(V_ph*sin(phi)- I_a*X_s)^2) and solving for V_ph

+p=[1 -941.53 -11399574.87]

+roots(p) 

+V_ph=ans(1) //second root is ignored as its -ve

+V_L=V_ph*sqrt(3)

+regulation2=100*(E_ph-V_ph)/V_ph

+delta_2 = asin( (tan(phi)*(V_ph*cos(phi_2)+I_a*R_a) -I_a*X_s )/E_ph   )

+printf('\n\n(ii)0.8 leading\nTerminal voltage is %.2f V\nVoltage regulation is %.2f percent\nLoad angle is %.2f degrees',V_L,regulation2,delta_2*(180/%pi))

diff --git a/1938/CH5/EX5.21/5_21.sce b/1938/CH5/EX5.21/5_21.sce
new file mode 100755
index 000000000..a9d0185f7
--- /dev/null
+++ b/1938/CH5/EX5.21/5_21.sce
@@ -0,0 +1,30 @@
+clc,clear

+printf('Example 5.21\n\n')

+

+V_ph=2000

+R_a=0.8

+I_sc=100,I_a=I_sc

+V_OC=500

+I_f=2.5

+Z_s=V_OC/I_sc

+

+X_s=sqrt(Z_s^2- R_a^2)

+I_a_FL=100

+

+//Part(i)

+phi1=acos(1) //and lagging

+E_ph1=sqrt((V_ph*cos(phi1)+I_a*R_a)^2+(V_ph*sin(phi1)+I_a*X_s)^2)

+regulation1=100*(E_ph1-V_ph)/V_ph

+printf('Regulation at upf is %.2f percent\n',regulation1)

+

+//Part(ii)

+phi2=acos(0.8) 

+E_ph2=sqrt((V_ph*cos(phi2)+I_a*R_a)^2+(V_ph*sin(phi2)-I_a*X_s)^2)

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf('Regulation at 0.8 leading pf is %.2f percent\n',regulation2)

+

+//Part(iii)

+phi3=acos(0.71) 

+E_ph3=sqrt((V_ph*cos(phi3)+I_a*R_a)^2+(V_ph*sin(phi3)+I_a*X_s)^2)

+regulation3=100*(E_ph3-V_ph)/V_ph

+printf('Regulation at 0.71 lagging pf is %.2f percent\n',regulation3)

diff --git a/1938/CH5/EX5.22/5_22.sce b/1938/CH5/EX5.22/5_22.sce
new file mode 100755
index 000000000..da18b21ca
--- /dev/null
+++ b/1938/CH5/EX5.22/5_22.sce
@@ -0,0 +1,34 @@
+clc,clear

+printf('Example 5.22\n\n')

+

+V=600

+VA=60*10^3

+I_sc=210

+V_oc=480

+I_f=10

+R_a=0.2

+

+I=VA/V        //VA=V*I and alternator is single phase

+I_a=I

+

+Z_s=V_oc/I_sc  //Synchronous Impedance

+X_s=sqrt(Z_s^2-R_a^2) //SYnchronous Reactance

+printf('Synchronous impedances is %f ohms and synchronous reactance is %f ohms\n',Z_s,X_s)

+

+//PART (i)

+phi1=acos(0.8) //and lagging

+E1=sqrt((V*cos(phi1)+I_a*R_a)^2+(V*sin(phi1)+I_a*X_s)^2) //plus sign for lagging power factor

+regulation1=100*(E1-V)/V

+printf('\nRegulation at 0.8 lagging pf is %.2f percent ',regulation1 )

+

+//PART (ii)

+phi2=acos(1) 

+E2=sqrt((V*cos(phi2)+I_a*R_a)^2+(V*sin(phi2)+I_a*X_s)^2) 

+regulation2=100*(E2-V)/V

+printf('\nRegulation at UNITY pf is %.2f percent ',regulation2 )

+

+//PART (iii)

+phi3=acos(0.6) //and leading 

+E3=sqrt((V*cos(phi3)+I_a*R_a)^2+(V*sin(phi3)-I_a*X_s)^2) //minus sign for leading power factor

+regulation3=100*(E3-V)/V

+printf('\nRegulation at 0.6 leading pf is %.2f percent ',regulation3 )

diff --git a/1938/CH5/EX5.23/5_23.sce b/1938/CH5/EX5.23/5_23.sce
new file mode 100755
index 000000000..b3c05a535
--- /dev/null
+++ b/1938/CH5/EX5.23/5_23.sce
@@ -0,0 +1,23 @@
+clc,clear

+printf('Example 5.23\n\n')

+

+V_L=3300, V_ph=V_L/sqrt(3)

+I_a=100

+I_f=5

+V_OC_line=900 ,V_OC_ph=V_OC_line/sqrt(3) 

+R_a=0.8 //armature resistance

+I_aph=I_a

+Z_s=V_OC_ph/I_aph

+X_s=sqrt(Z_s^2-R_a^2) //synchronous reactance

+

+//Part(i)

+phi1=acos(0.8) //and lagging

+E_ph1=sqrt((V_ph*cos(phi1)+I_a*R_a)^2+(V_ph*sin(phi1)+I_a*X_s)^2)

+regulation1=100*(E_ph1-V_ph)/V_ph

+printf('Regulation at 0.8 lagging is %.2f percent\n',regulation1)

+

+//Part(ii)

+phi2=acos(0.8)  //and leading

+E_ph2=sqrt((V_ph*cos(phi2)+I_a*R_a)^2+(V_ph*sin(phi2)-I_a*X_s)^2)

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf('Regulation at 0.8 leading pf is %.2f percent\n',regulation2)

diff --git a/1938/CH5/EX5.24/5_24.sce b/1938/CH5/EX5.24/5_24.sce
new file mode 100755
index 000000000..72aa0071d
--- /dev/null
+++ b/1938/CH5/EX5.24/5_24.sce
@@ -0,0 +1,33 @@
+clc,clear

+printf('Example 5.24\n\n')

+

+V_L=13500

+R_a=1.5 , X_s=30 //armature resistance and synchronous reactance

+V_ph=V_L/sqrt(3)

+

+//CASE 1

+phi1=acos(0.8)

+P_out=1280*10^3

+I_L= P_out/ (sqrt(3)*V_L*cos(phi1) )    //because P_out=sqrt(3)*V_L*I_L*cos(phi)

+

+I_a=I_L

+E_ph=sqrt((V_ph*cos(phi1)+I_a*R_a)^2+(V_ph*sin(phi1)+I_a*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Regulation at 0.8 lagging power factor is %.2f percent',regulation)

+

+//Case 2

+phi2=acos(1)

+I_L= P_out/ (sqrt(3)*V_L*cos(phi2) )    //because P_out=sqrt(3)*V_L*I_L*cos(phi)

+

+I_a=I_L

+E_ph=sqrt((V_ph*cos(phi2)+I_a*R_a)^2+(V_ph*sin(phi2)+I_a*X_s)^2)

+regulation2=100*(E_ph-V_ph)/V_ph

+printf('\nRegulation at unity power factor is %.2f percent',regulation2)

+

+//case 3

+phi3=acos(0.8)

+I_L= P_out/ (sqrt(3)*V_L*cos(phi3) )    //because P_out=sqrt(3)*V_L*I_L*cos(phi)

+I_a=I_L

+E_ph=sqrt((V_ph*cos(phi3)+I_a*R_a)^2+(V_ph*sin(phi3)-I_a*X_s)^2)// minus sign in the second bracket beacuse of leading pf

+regulation3=100*(E_ph-V_ph)/V_ph

+printf('\nRegulation at 0.8 leading power factor is %.2f percent',regulation3)

diff --git a/1938/CH5/EX5.26/5_26.sce b/1938/CH5/EX5.26/5_26.sce
new file mode 100755
index 000000000..2824890b4
--- /dev/null
+++ b/1938/CH5/EX5.26/5_26.sce
@@ -0,0 +1,21 @@
+clc,clear

+printf('Example 5.26\n\n')

+

+V_L=11*10^3

+VA_rating=10^6

+R_a=2.2 //alternator resistance

+phi=acos(0.8)

+

+I_L=VA_rating/(sqrt(3)*V_L)//VA=sqrt(3)V_L*I_L

+I_a=I_L

+V_ph=V_L/sqrt(3)

+regulation=24

+

+E_ph= ((regulation/100)+1)*V_ph    // because regulation=100*(E_ph-V_ph)/V_ph

+//using E_ph=sqrt((V_ph*cos(phi)+I_a*R_a)^2+(V_ph*sin(phi)+I_a*X_s)^2)

+X_s=(sqrt(E_ph^2-((V_ph*cos(phi)+I_a*R_a)^2))-V_ph*sin(phi))*(1/I_a)

+

+phi1=acos(0.8)

+E_ph=sqrt((V_ph*cos(phi1)+I_a*R_a)^2+(V_ph*sin(phi1)-I_a*X_s)^2)

+regulation1=100*(E_ph-V_ph)/V_ph

+printf('\nRegulation at 0.8 leading power factor is %.2f percent',regulation1)

diff --git a/1938/CH5/EX5.27/5_27.sce b/1938/CH5/EX5.27/5_27.sce
new file mode 100755
index 000000000..2a0892ccc
--- /dev/null
+++ b/1938/CH5/EX5.27/5_27.sce
@@ -0,0 +1,23 @@
+clc,clear

+printf('Example 5.27\n\n')

+

+V_L=220

+VA=100*10^3

+R_a=0.1 //effective resistacne of alternator

+X_a=0.5 //leakage reactance

+X_ar=2*X_a

+

+Z_s=complex(R_a,X_a+X_ar)

+

+//Part(1)

+phi=acos(0.4)

+V_ph=V_L/sqrt(3)

+I_L=VA/(sqrt(3)*V_L)//VA=sqrt(3)*V_L*I_L

+I_a=I_L

+E_ph=sqrt((V_ph*cos(phi)+I_a*R_a)^2+(V_ph*sin(phi)+I_a*(X_a+X_ar))^2)

+printf('(i)Required noload voltage is %.3f V',E_ph)

+

+//Part(2)

+V_ph2=0

+E_ph2=sqrt((V_ph2*cos(phi)+I_a*R_a)^2+(V_ph2*sin(phi)+I_a*(X_a+X_ar))^2)

+printf('\n(ii)Required noload voltage is %.3f V',E_ph2)

diff --git a/1938/CH5/EX5.28/5_28.jpg b/1938/CH5/EX5.28/5_28.jpg
new file mode 100755
index 000000000..9f409a31b
--- /dev/null
+++ b/1938/CH5/EX5.28/5_28.jpg
diff --git a/1938/CH5/EX5.28/5_28.sce b/1938/CH5/EX5.28/5_28.sce
new file mode 100755
index 000000000..066180d53
--- /dev/null
+++ b/1938/CH5/EX5.28/5_28.sce
@@ -0,0 +1,26 @@
+clc,clear

+printf('Example 5.28\n\n')

+

+V_L=2000,V_ph=V_L/sqrt(3)

+VA=1000*10^3

+I_L=VA/(sqrt(3)*V_L)    //because VA=sqrt(3)*V_L*I_L

+I_aph=I_L

+

+I_f=28.5//for this I_aph=288.67513 as obtained from SCC graph

+V_oc_ph=1060//for I_f=28.5 as obtained fromOCC graph

+Z_s=V_oc_ph/I_aph

+R_a=0.2 //armature effective resistance

+X_s=sqrt( Z_s^2-R_a^2 )

+

+//Part(i)

+phi1=acos(0.8)//lagging

+E_ph1=sqrt((V_ph*cos(phi1)+I_aph*R_a)^2+(V_ph*sin(phi1)+I_aph*X_s)^2)

+regulation1=100*(E_ph1-V_ph)/V_ph

+printf("(i)Full-load percentage regulation at 0.8 pf lagging is %.2f percent",regulation1)

+

+//Part(ii)

+phi2=acos(0.8)//leading

+E_ph2=sqrt((V_ph*cos(phi2)+I_aph*R_a)^2+(V_ph*sin(phi2)-I_aph*X_s)^2)

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf("\n(ii)Full-load percentage regulation at 0.8 pf leading is %.2f percent\n\n",regulation2)

+printf('Note that the answer mismatches because of calculation mistake done in the last step of part 1')

diff --git a/1938/CH5/EX5.29/5_29.sce b/1938/CH5/EX5.29/5_29.sce
new file mode 100755
index 000000000..f951f96e3
--- /dev/null
+++ b/1938/CH5/EX5.29/5_29.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 5.29\n\n')

+

+V_L=3300

+VA=200*10^3

+R_a=0.6, X_s=6//armature resistance and synchronous reactance

+

+I_L=VA/(sqrt(3)*V_L)//VA=sqrt(3)V_L*I_L

+I_a=I_L

+V_ph=V_L/sqrt(3)

+phi=acos(0.8)

+E_ph=sqrt((V_ph*cos(phi)+I_a*R_a)^2+(V_ph*sin(phi)+I_a*X_s)^2)

+

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Regulation at 0.8 lagging power factor is %.3f percent',regulation)

+printf('\n Note :\n Regulation is positive for lagging power factor loads')

diff --git a/1938/CH5/EX5.3/5_3.sce b/1938/CH5/EX5.3/5_3.sce
new file mode 100755
index 000000000..2737d3177
--- /dev/null
+++ b/1938/CH5/EX5.3/5_3.sce
@@ -0,0 +1,14 @@
+clc,clear

+printf('Example 5.3\n\n')

+

+//full load

+V_L_FL=1100

+V_ph_FL=V_L_FL/sqrt(3)

+

+//no load

+V_L_NL=1266

+E_line=V_L_NL

+E_ph=E_line/sqrt(3)

+regulation=100*(E_ph-V_ph_FL)/V_ph_FL

+

+printf('Regulation at full load is %.2f percent',regulation)

diff --git a/1938/CH5/EX5.30/5_30.sce b/1938/CH5/EX5.30/5_30.sce
new file mode 100755
index 000000000..25e9c8f1a
--- /dev/null
+++ b/1938/CH5/EX5.30/5_30.sce
@@ -0,0 +1,23 @@
+clc,clear

+printf('Example 5.30\n\n')

+

+V_L=2300   ,  V_ph= V_L/sqrt(3)

+f=50,R_a=0.2 //armature resistance

+I_sc=150

+V_OC_line=780   , V_OC_ph=V_OC_line/sqrt(3)

+

+Z_s= V_OC_ph/I_sc

+X_s =  sqrt(Z_s^2 - R_a^2)

+I_aph=25 , I_aFL=I_aph

+

+//part(i)

+phi= acos(0.8)  //lag

+E_ph = sqrt((V_ph*cos(phi)+I_aph*R_a)^2 +(V_ph*sin(phi)+ I_aph*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Voltage regulation at 0.8 pf lagging is %.3f percent\n',regulation)

+

+//part(ii)

+phi2= acos(0.8)  //lead

+E_ph2 = sqrt((V_ph*cos(phi2)+I_aph*R_a)^2 +(V_ph*sin(phi2)- I_aph*X_s)^2 )

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf('Voltage regulation at 0.8 pf leading is %.3f percent',regulation2)

diff --git a/1938/CH5/EX5.4/5_4.jpg b/1938/CH5/EX5.4/5_4.jpg
new file mode 100755
index 000000000..49ca399ad
--- /dev/null
+++ b/1938/CH5/EX5.4/5_4.jpg
diff --git a/1938/CH5/EX5.4/5_4.sce b/1938/CH5/EX5.4/5_4.sce
new file mode 100755
index 000000000..229ecfe75
--- /dev/null
+++ b/1938/CH5/EX5.4/5_4.sce
@@ -0,0 +1,26 @@
+clc,clear

+printf('Example 5.4\n\n')

+

+V_L=866

+VA=100*10^3

+I_L=VA/(sqrt(3)*V_L)    //because VA=sqrt(3)*V_L*I_L

+I_aph=I_L//full load and star connected alternator

+V_ph=V_L/sqrt(3)

+

+//Graph is plotted and V_oc_ph and I_asc_Ph is obtained for 

+//SCC for I_asc=66.67 A,I_f=2.4 A

+//OCC for I_f=2.4 A,V_oc_ph=240 V

+

+//for measruemnt of impedance

+V_oc_ph=240 //for I_f=2.4..From o.c.c graph

+I_asc_ph=66.67 //for I_f=2.4...From s.c.c graph

+Z_s=V_oc_ph/I_asc_ph

+R_a=0.15

+X_s=sqrt( Z_s^2-R_a^2 )

+

+V_ph_FL=500

+phi=acos(0.8)  //lagging pf

+E_ph=sqrt((V_ph_FL*cos(phi)+I_aph*R_a)^2+(V_ph_FL*sin(phi)+I_aph*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+

+printf('Full-load regulation at 0.8 lagging pf is %.2f percent ',regulation )

diff --git a/1938/CH5/EX5.5/5_5.sce b/1938/CH5/EX5.5/5_5.sce
new file mode 100755
index 000000000..dedeac2b1
--- /dev/null
+++ b/1938/CH5/EX5.5/5_5.sce
@@ -0,0 +1,24 @@
+clc,clear

+printf('Example 5.5\n\n')

+

+V_OC_line=230,I_asc=12.5  // when I_f=0.38

+V_OC_ph=V_OC_line/sqrt(3)

+Z_s=V_OC_ph/I_asc 

+

+R_a=1.8/2  //1.8 is between terminals..0.9 is per phase

+X_s=sqrt(Z_s^2-R_a^2)

+

+I_a=10// when regulation is needed

+V_L=230

+V_ph=V_L/sqrt(3)

+

+//Part(i)

+phi1=acos(0.8) //and lagging

+E_ph1=sqrt((V_ph*cos(phi1)+I_a*R_a)^2+(V_ph*sin(phi1)+I_a*X_s)^2)

+regulation1=100*(E_ph1-V_ph)/V_ph

+printf('Regulation for 10 A at 0.8 lagging pf is %.2f percent\n',regulation1)

+//Part(ii)

+phi2=acos(0.8) //and leading

+E_ph2=sqrt((V_ph*cos(phi2)+I_a*R_a)^2+(V_ph*sin(phi2)-I_a*X_s)^2)

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf('Regulation for 10 A at 0.8 leading pf is %.2f percent\n',regulation2)

diff --git a/1938/CH5/EX5.6/5_6.sce b/1938/CH5/EX5.6/5_6.sce
new file mode 100755
index 000000000..e6897099d
--- /dev/null
+++ b/1938/CH5/EX5.6/5_6.sce
@@ -0,0 +1,37 @@
+clc,clear

+printf('Example 5.6\n\n')

+

+phi=acos(0.8)

+VA=1000*10^3

+V_L=1905

+V_ph=V_L/sqrt(3)

+R_a=0.2//Armature reactance per phase

+

+//Part(i)

+//Ampere-turn method

+I_L=VA/(sqrt(3)*V_L)

+I_aph=I_L

+V_dash=V_ph+I_aph*R_a*cos(phi)//V_dash is a dummy quantity and has no significance..it's used only for mapping correcponding current

+F_o=32 //F_o corresponds to voltage V_dash=1148.5 from O.C.C graph

+F_AR=27.5 //Field current required to circulate full-load short circuit current of 303.07A.From SCC F_AR=27.5

+F_R = sqrt(    F_o^2 + F_AR^2-2*F_o*F_AR*cos(phi+%pi/2) )//Using Cosine rule

+

+// for F_R=53.25, E_ph=1490 V from O.C.C

+E_ph=1490

+regulation1=100*(E_ph-V_ph)/V_ph

+printf('Regulation on full-load by ampere-turn method is %.2f percent',regulation1)

+

+//Part (ii)

+//Synchronous Impedance method

+

+I_sc=I_L

+I_aph2=I_sc

+I_f=27.5

+

+V_OC_ph=1060 //corresponding to I-f=27.5 in the graph

+Z_s=V_OC_ph/I_aph2

+X_s=sqrt(Z_s^2-R_a^2)

+

+E_ph2= sqrt( (V_ph*cos(phi)+I_aph2*R_a)^2+(V_ph*sin(phi)+I_aph2*X_s)^2 )   //from phasor diagram

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf('\nRegulation on full-load by synchronous impedance method is %.2f percent',regulation2)

diff --git a/1938/CH5/EX5.6/5_6_1.jpg b/1938/CH5/EX5.6/5_6_1.jpg
new file mode 100755
index 000000000..07f48b8e1
--- /dev/null
+++ b/1938/CH5/EX5.6/5_6_1.jpg
diff --git a/1938/CH5/EX5.6/5_6_2.jpg b/1938/CH5/EX5.6/5_6_2.jpg
new file mode 100755
index 000000000..63e0999bd
--- /dev/null
+++ b/1938/CH5/EX5.6/5_6_2.jpg
diff --git a/1938/CH5/EX5.7/5_7.sce b/1938/CH5/EX5.7/5_7.sce
new file mode 100755
index 000000000..e4f2d8c56
--- /dev/null
+++ b/1938/CH5/EX5.7/5_7.sce
@@ -0,0 +1,36 @@
+clc,clear

+printf('Example 5.7\n\n')

+

+//case(i)

+V_L=440

+V_ph=V_L/sqrt(3)

+phi=acos(0.8)

+

+//armature resistance drop from the graph

+//RS=1.1 cm and scale =50 V/cm

+arm_leak_resis= 1.1*50    //armature leakage resistance

+

+OB=V_ph*cos(phi)

+AB=V_ph*sin(phi) + arm_leak_resis

+E_1ph= sqrt( OB^2+AB^2   )

+

+F_f1=6.1  //corresponding value from OCC

+F_AR=3.1*1

+

+F_R= sqrt(   F_f1^2 + F_AR^2 -2*F_f1*F_AR*cosd(90+acosd(0.8))           )

+E_ph=328 //voltage corresponding to F_R=8.33 A from OCC graph

+regulation1= 100*(E_ph - V_ph)/V_ph

+printf('(i)Regulation for 0.8 pf lagging is %.2f percent \n',regulation1)

+

+//case(ii)

+

+OC=V_ph*cos(phi)

+BC=V_ph*sin(phi) - arm_leak_resis

+E_1ph= sqrt( OC^2+BC^2   )

+

+F_f1=6.1  //corresponding value from OCC

+F_R= sqrt(   F_f1^2 + F_AR^2 -2*F_f1*F_AR*cosd(90-acosd(0.8))           )

+E_ph=90 //volatge corresponding to F_R=3.34 A from OCC graph

+regulation2= 100*(E_ph - V_ph)/V_ph

+printf('(ii)Regulation for 0.8 pf leading is %.2f percent \n',regulation2)

+printf('\nThe answer in part (ii) doesnt match with textbook because of calculation mistake done in last step in the textbook')

diff --git a/1938/CH5/EX5.7/5_7_1.jpg b/1938/CH5/EX5.7/5_7_1.jpg
new file mode 100755
index 000000000..8766a0e4a
--- /dev/null
+++ b/1938/CH5/EX5.7/5_7_1.jpg
diff --git a/1938/CH5/EX5.7/5_7_2.jpg b/1938/CH5/EX5.7/5_7_2.jpg
new file mode 100755
index 000000000..966fc1f2f
--- /dev/null
+++ b/1938/CH5/EX5.7/5_7_2.jpg
diff --git a/1938/CH5/EX5.8/5_8.sce b/1938/CH5/EX5.8/5_8.sce
new file mode 100755
index 000000000..831c9c2dd
--- /dev/null
+++ b/1938/CH5/EX5.8/5_8.sce
@@ -0,0 +1,16 @@
+clc,clear

+printf('Example 5.8\n\n')

+

+P=1200*10^3

+V_line=12000

+R_a=2,X_s=35//armature resistance and synchronous reactance

+phi=acos(0.8)

+

+

+I_L=P/(sqrt(3)*V_line*cos(phi))

+I_a=I_L

+V_ph=V_line/sqrt(3)

+E_ph=sqrt((V_ph*cos(phi)+I_a*R_a)^2+(V_ph*sin(phi)+I_a*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+

+printf('Regulation at 0.8 lag power factor is %.2f percent',regulation)

diff --git a/1938/CH5/EX5.9/5_9.sce b/1938/CH5/EX5.9/5_9.sce
new file mode 100755
index 000000000..1641e6bf0
--- /dev/null
+++ b/1938/CH5/EX5.9/5_9.sce
@@ -0,0 +1,26 @@
+clc,clear

+printf('Example 5.9\n\n')

+

+V_L=11000  , V_ph= V_L/sqrt(3)

+VA=1000*1000

+I_L=VA/(V_L*sqrt(3))

+

+V_OC_ph=433/sqrt(3)

+I_asc_ph=I_L

+

+Z_s=V_OC_ph /I_asc_ph  //ohms per phase

+R_a=0.45 //ohms per phase

+X_s=sqrt(Z_s^2-R_a^2)

+

+//part(i)

+phi=acos(0.8) //lagging

+E_ph = sqrt((V_ph*cos(phi)+I_L*R_a)^2 +(V_ph*sin(phi)+ I_L*X_s)^2)

+regulation=100*(E_ph-V_ph)/V_ph

+printf('Voltage regulation at 0.8 pf lagging is %f percent\n',regulation)

+

+//part(ii)

+phi=acos(0.8) //leading

+E_ph2 = sqrt((V_ph*cos(phi)+I_L*R_a)^2 +(V_ph*sin(phi)- I_L*X_s)^2)

+regulation2=100*(E_ph2-V_ph)/V_ph

+printf('Voltage regulation at 0.8 pf lagging is %f percent\n',regulation2)

+printf('\nAnswer mismatches due to improper approximation')