initial commit / add all books

21 files changed, 593 insertions, 0 deletions

diff --git a/1370/CH4/EX4.1/Exp4_1.sce b/1370/CH4/EX4.1/Exp4_1.sce
new file mode 100755
index 000000000..96f3dfd1a
--- /dev/null
+++ b/1370/CH4/EX4.1/Exp4_1.sce
@@ -0,0 +1,12 @@
+//Example 4.1

+clc

+n=120/8

+format(3)

+disp(n,"n = slots/pole =")

+m=15/3

+disp(m,"m = slots/pole/phase = n/3 =")

+beta=180/15

+disp(beta,"beta(in degree) = 180/n =")

+kd=(sind(30)/(5*sind(6)))

+format(6)

+disp(kd,"Therefore,  K_d = sin(m*beta/2) / m*sin(beta/2) =")

diff --git a/1370/CH4/EX4.10/Exp4_10.sce b/1370/CH4/EX4.10/Exp4_10.sce
new file mode 100755
index 000000000..f52f6f7df
--- /dev/null
+++ b/1370/CH4/EX4.10/Exp4_10.sce
@@ -0,0 +1,39 @@
+//Exmaple 4.10

+clc

+disp("N_s = 250 r.p.m.,  f = 50 Hz")

+disp("slots = 288,  E_line = 6600 V")

+disp("N_s = 120*f/P")

+p=(120*50)/250

+format(3)

+disp(p,"Therefore,  P =")

+n=288/24

+disp(n,"n = slots/pole =")

+m=12/3

+disp(m,"m = n/2 =")

+beta=180/12

+disp(beta,"beta = 180/n =")

+kd=sind(30)/(4*sind(7.5))

+format(7)

+disp(kd,"Therefore,  K_d = sin(m*beta/2) / m*sin(beta/2) =")

+disp("Now coil is short pitched by 2 slots")

+al=2*15

+disp(al,"Therefore,  alpha = angle of short pitch = 2 * beta =")

+kc=cosd(15)

+disp(kc,"Therefore,  K_c = cos(alpha/2) =")

+disp("Each coil consists of 16 turns, i.e. in a slot each coil side consists of 16 conductors as shown in the fig.4.42 and in each slot there are 2 coil sides. So each slot consists of 16 per coil side x 2 i.e. 32 conductors.")

+disp("Therefore,  conductors/slot = 32")

+disp("Therefore,  total conductors = slots x conductors/slot")

+z=288*32

+format(5)

+disp(z,"Therefore,  Z =")

+zp=9216/3

+disp(zp,"Therefore,  Z_ph = conductors/phase =")

+tp=3072/2

+disp(tp,"Therefore,  T_ph = Z_ph/2 =               ... 2 conductors -> 1 turn")

+ep=6600/sqrt(3)

+format(8)

+disp(ep,"Now  E_ph(in V) = E_line / sqrt(3) =")

+disp("E_ph = 4.44*K_c*K_d*phi*f*T_ph")

+phi=(3810.51/(4.44*0.9659*0.9576*50*1536))*10^3

+format(3)

+disp(phi,"Therefore,  phi(in mWb) =")

diff --git a/1370/CH4/EX4.11/Exp4_11.sce b/1370/CH4/EX4.11/Exp4_11.sce
new file mode 100755
index 000000000..7397e1df2
--- /dev/null
+++ b/1370/CH4/EX4.11/Exp4_11.sce
@@ -0,0 +1,46 @@
+//Example 4.11

+clc

+disp("P = 12,  N_s = 600 r.p.m")

+f=(12*600)/120

+format(3)

+disp(f,"Therefore,  f(in Hz) = P*N_s/120 =")

+disp("(i) Average value of e.m.f in a conductor = 2*f*phi")

+rms=1.11*2*60*0.05

+format(5)

+disp(rms,"Therefore,  r.m.s value(in V) = 1.11*2*f*phi =")

+disp("(ii) Average value of e.m.f in a turn = 4*f*phi")

+disp("As 2 conductors joined properly form a turn")

+rms=1.11*4*60*0.05

+format(6)

+disp(rms,"Therefore,  r.m.s value(in V) = 1.11*4*f*phi =")

+disp("(iii) Now each slot has 10 conductors and 2 coil sides. So,")

+c=10/2

+disp(c,"conductors/coil side = 10/2 =")

+disp("Such coil sides are connected to another coil sides to form a coil. So in a coil there are 5 turns as shown in fig.4.43")

+rmss=13.32*5

+format(5)

+disp(rmss,"Therefore,  R.M.S value of e.m.f in a coil(in V) = R.M.S value of e.m.f/turn * Number of turns/coil =")

+disp("(iv) Now total conductors  Z = conductors/slots * Number of slots")

+z=10*180

+disp(z,"Therefore,  Z =")

+zph=1800/3

+disp(zph,"Therefore,  Z_ph = Z/3 =")

+tph=600/2

+disp(tph,"T_ph = Z_ph/2 =")

+n=180/12

+disp(n,"And  n = slots/pole =")

+m=15/3

+disp(m,"m = n/3 =")

+beta=180/15

+disp(beta,"beta(in degree) =")

+kd=sind(30)/(5*sind(6))

+format(7)

+disp(kd,"Therefore,  K_d = sin(m*beta/2) / m*sin(beta/2) =")

+disp("E_ph = R.M.S value per turn*T_ph*K_d*K_c")

+ep=13.32*300*0.9566*1

+format(8)

+disp(ep,"Therefore,  E_ph(in V) =")

+disp("or  E_ph = 4.44*K_c*K_d*phi*f*T_ph")

+eph=4.44*0.9566*0.05*60*300

+format(8)

+disp(eph,"Therefore,  E_ph(in V) =")

diff --git a/1370/CH4/EX4.12/Exp4_12.sce b/1370/CH4/EX4.12/Exp4_12.sce
new file mode 100755
index 000000000..e0b100f5d
--- /dev/null
+++ b/1370/CH4/EX4.12/Exp4_12.sce
@@ -0,0 +1,36 @@
+//Example 4.12

+clc

+disp("P = 6,  f = 50 Hz,  n = 12 slots/pole, 4 conductors/slot")

+disp("For full pitch,  n = 12 slots/pole")

+ap=60/6

+format(4)

+disp(ap,"Actual pitch of winding(in slots) = 5/6 * n =")

+ws=12-10

+disp(ws,"so winding shorted by(in slots) =")

+disp("Therefore,  alpha = short pitch angle = 2 slot angle = 2*beta")

+beta=180/12

+disp(beta,"beta(in degree) =")

+alp=2*15

+disp(alp,"Therefore,  alpha(in degree) = 2*beta =")

+kc=cosd(15)

+format(7)

+disp(kc,"Therefore,  K_c = cos(alpha/2) =")

+m=12/3

+disp(m,"m(in slots/pole/phase) = n/3 =")

+kd=sind(30)/(4*sind(7.5))

+format(8)

+disp(kd,"Therefore,  K_d = sin(m*beta/2) / m*sin(beta/2) =")

+ts=12*6

+disp(ts,"Total slots = n*P =")

+z=72*4

+disp(z,"Therefore,  Z = total conductors =")

+zph=288/3

+disp(zph,"Therefore,  Z_ph = Z/3 =")

+tph=96/2

+disp(tph,"T_ph = Z_ph/2 =")

+disp("Therefore,  E_ph = 4.44*K_c*K_d*phi*f*T_ph")

+eph=(4.44*0.9659*0.95766*1.5*50*48)*10^-3

+format(8)

+disp(eph,"Therefore,  E_ph(in kV) =")

+el=sqrt(3)*14.7852

+disp(el,"Therefore,  E_line(in kV) = sqrt(3)*E_ph =")

diff --git a/1370/CH4/EX4.13/Exp4_13.sce b/1370/CH4/EX4.13/Exp4_13.sce
new file mode 100755
index 000000000..4bf56f345
--- /dev/null
+++ b/1370/CH4/EX4.13/Exp4_13.sce
@@ -0,0 +1,11 @@
+//Example 4.13

+clc

+disp("The coil span of 120 degree is shown in the fig.4.44")

+disp("The angle of shorts pitch is,")

+alp=180-120

+format(3)

+disp(alp,"alpha(in degree) = 180 - coil span =")

+kc=cosd(30)

+format(6)

+disp("The chording factor is,")

+disp(kc,"K_c = cos(alpha/2) =")

diff --git a/1370/CH4/EX4.14/Exp4_14.sce b/1370/CH4/EX4.14/Exp4_14.sce
new file mode 100755
index 000000000..a9e541a07
--- /dev/null
+++ b/1370/CH4/EX4.14/Exp4_14.sce
@@ -0,0 +1,15 @@
+//Example 4.14

+clc

+disp("V_ph = 200 V, 60 kVA,  R_a = 0.016 ohm,  X_s = 0.07 ohm")

+disp("VA = V_ph*I_ph    i.e. 60*10^3 = 200*I_ph        ...Single phase")

+disp("Therefore,  I_ph = 300 A = I_a              ...Full load current")

+disp("(a) cos(phi) = 1,  sin(phi) = 0")

+eph=sqrt((((200+((300*0.016)))^2)+((300*0.07)^2)))

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (I_a*X_a)^2")

+format(9)

+disp(eph,"E_ph(in V) =")

+disp("(b) cos(phi) = 0.7 lagging,  sin(phi) = 0.714")

+ephi=sqrt(((((200*0.7)+(300*0.016))^2)+(((200*0.7141)+(300*0.07))^2)))

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+format(9)

+disp(ephi,"E_ph(in V) =")

diff --git a/1370/CH4/EX4.15/Exp4_15.sce b/1370/CH4/EX4.15/Exp4_15.sce
new file mode 100755
index 000000000..b275f92c0
--- /dev/null
+++ b/1370/CH4/EX4.15/Exp4_15.sce
@@ -0,0 +1,21 @@
+//Example 4.15

+clc

+disp("V_ph = 550 V, 55 kVA,  R_a = 0.2 ohm")

+disp("I_f = 10 A,  I_ssc = 200 A,  V_oc = 450 V")

+za=450/200

+format(5)

+disp(za,"Therefore,  Z_s(in ohm) = V_oc / I_ssc |same I_f =")

+xs=sqrt((2.25^2)-(0.2^2))

+format(7)

+disp(xs,"(a)  X_s(in ohm) = sqrt(Z_a^2 - R_a^2) =")

+iph=(55*10^3)/550

+disp("VA = V_ph*I_ph           ...As single phase")

+disp(iph,"Therefore,  I_ph(in A) = I_a =        ...Full load armature current")

+disp("(b) cos(phi) = 0.8 lagging,  sin(phi) = 0.6")

+ephi=sqrt(((((550*0.8)+(100*0.2))^2)+(((550*0.6)+(100*2.2411))^2)))

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+format(9)

+disp(ephi,"E_ph(in V) =")

+r=((720.1652-550)/550)*100

+format(6)

+disp(r,"Therefore,  %R = (E_ph-V_ph / V_ph)*100 = ")

diff --git a/1370/CH4/EX4.16/Exp4_16.sce b/1370/CH4/EX4.16/Exp4_16.sce
new file mode 100755
index 000000000..c944e60d3
--- /dev/null
+++ b/1370/CH4/EX4.16/Exp4_16.sce
@@ -0,0 +1,18 @@
+//Example 4.16

+clc

+disp("V_ph = 2200 V,  f = 50 Hz, 440 kVA,  R_a = 0.5 ohm")

+disp("I_aph = 200 A = I_ac,  V_oc = 1160 V,  I_f = 40 A")

+za=1160/200

+format(4)

+disp(za,"(a)  Z_s(in ohm) = V_oc/I_ssc |same I_f =")

+xs=sqrt((5.8^2)-(0.5^2))

+format(7)

+disp(xs,"(b)  X_s(in ohm) = sqrt(Z_a^2 - R_a^2) =")

+disp("(c)  cos(phi) = 0.707 leading,  sin(phi) = 0.707")

+ephi=sqrt(((((2200*0.707)+(200*0.5))^2)+(((2200*0.707)-(200*5.7784))^2)))

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)-I_a*R_a)^2")

+format(10)

+disp(ephi,"E_ph(in V) =")

+r=((1702.9754-2200)/2200)*100

+format(7)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

diff --git a/1370/CH4/EX4.17/Exp4_17.sce b/1370/CH4/EX4.17/Exp4_17.sce
new file mode 100755
index 000000000..56fb7534e
--- /dev/null
+++ b/1370/CH4/EX4.17/Exp4_17.sce
@@ -0,0 +1,31 @@
+//Example 4.17

+clc

+disp("Assume star connected alternator")

+disp("R_a+R_a = V_dc/I_dc")

+disp("2R_a = 6/10")

+ra=0.6/2

+format(4)

+disp(ra,"Therefore,  R_a(in ohm/ph) =")

+disp("V_oc(line) = 420,  V_L = 1100 V, 100 kVA")

+disp("Therefore,  VA = sqrt(3)*V_L*I_L")

+il=(100*10^3)/(sqrt(3)*1100)

+format(8)

+disp(il,"Therefore,  I_L(in A) = I_aph =")

+disp("Therefore,  Rated armature current = 52.4864 A = I_ssc")

+zs=(420/sqrt(3))/52.4864

+format(5)

+disp(zs,"Therefore,  Z_s(in ohm/ph) = V_oc(ph) / I_ssc(ph) =")

+xs=sqrt((4.62^2)-(0.3^2))

+format(7)

+disp(xs,"Therefore,  X_s(in ohm/ph) = sqrt(Z_a^2 - R_a^2) =")

+disp("For cos(phi) = 0.8 lagging,  sin(phi) = 0.6")

+disp("E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+vph=1100/sqrt(3)

+format(8)

+disp(vph,"V_ph(in V) = V_L/sqrt(3) =")

+ephi=sqrt(((((635.085*0.8)+(52.4864*0.3))^2)+(((635.085*0.6)+(52.4864*4.6102))^2)))

+format(9)

+disp(ephi,"Therefore,  E_ph(in V) =")

+r=((813.9654-635.085)/635.085)*100

+format(8)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

diff --git a/1370/CH4/EX4.18/Exp4_18.sce b/1370/CH4/EX4.18/Exp4_18.sce
new file mode 100755
index 000000000..906a8c5af
--- /dev/null
+++ b/1370/CH4/EX4.18/Exp4_18.sce
@@ -0,0 +1,36 @@
+//Example 4.18

+clc

+disp("2R_a = 2  i.e.  R_a = 1 ohm/ph")

+disp("V_L = 3.6 kVA,  MVA = 1")

+disp("Therefore,  VA = sqrt(3)*V_L*I_L")

+il=(1*10^6)/(sqrt(3)*3.6*10^3)

+format(8)

+disp(il,"Therefore,  I_L(in A) = I_aph =         ...Star")

+disp("From the test results, obtain the open circuit and short circuit characteristics and obtain V_oc for full load I_sc of 160.373 A")

+disp("From the graph, for full load short circuit current of 160.37 A, I_f = 53 A and corresponding V_oc(line) = 2250 V")

+zs=(2250/sqrt(3))/160.37

+format(4)

+disp(zs,"Therefore,  Z_s(in ohm/ph) = V_ocph/I_scph |same I_f =")

+xs=sqrt((8.1^2)-(1^2))

+format(6)

+disp(xs,"Therefore,  X_s(in ohm/ph) = sqrt(Z_a^2 - R_a^2) =")

+vph=(3.6*10^3)/sqrt(3)

+format(8)

+disp(vph,"V_ph(in V) = V_L/sqrt(3) =")

+disp("I_aph = 160.37 A")

+disp("(i)  cos(phi) = 0.707 lagging,  sin(phi) = 0.707")

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+ephi=sqrt(((((2078.46*0.707)+(160.37*1))^2)+(((2078.46*0.707)+(160.37*8.038))^2)))

+format(10)

+disp(ephi,"Therefore,  E_ph(in V) =")

+r=((3204.0356-2078.46)/2078.46)*100

+format(6)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

+disp("(ii)  cos(phi) = 0.8 leading,  sin(phi) = 0.6")

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)-I_a*R_a)^2")

+ephi=sqrt(((((2078.46*0.8)+(160.37*1))^2)+(((2078.46*0.6)-(160.37*8.038))^2)))

+format(10)

+disp(ephi,"Substituting the values,  E_ph(in V) =")

+r=((1823.6271-2078.46)/2078.46)*100

+format(6)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

diff --git a/1370/CH4/EX4.19/Exp4_19.sce b/1370/CH4/EX4.19/Exp4_19.sce
new file mode 100755
index 000000000..8550f3227
--- /dev/null
+++ b/1370/CH4/EX4.19/Exp4_19.sce
@@ -0,0 +1,37 @@
+//Example 4.19

+clc

+disp("1 MVA,  V_L = 11 kV,  R_a = 0.6 ohm")

+disp("VA = sqrt(3)*V_L*I_L")

+il=(10^6)/(sqrt(3)*11*10^3)

+format(7)

+disp(il,"Therefore,  I_L(in A) = I_aph(full load) =")

+disp("Now I_f = 40 A for I_ssc = 52.486 A. To find Z_s, plot the O.C.C and obtain V_oc for I_f = 40 A")

+disp("From the graph, V_oc(line) = 6600 V for I_f = 40 A")

+zs=(6000/sqrt(3))/52.486

+format(3)

+disp(zs,"Therefore,  Z_s(in ohm) = V_ocph/I_ascph |same I_f =")

+xs=sqrt((66^2)-(0.6^2))

+format(7)

+disp(xs,"Therefore,  X_s(in ohm) = sqrt(Z_s^2 - R_a^2) =")

+disp("(a) cos(phi) = 0.8 lagging,  sin(phi) = 0.6, half load")

+ip=0.5*52.486

+format(7)

+disp(ip,"At half load,  I_aph(in A) = 1/2 * I_aph(FL) =")

+vp=(11*10^3)/sqrt(3)

+format(9)

+disp(vp,"V_ph(in V) = V_L/sqrt(3) =")

+disp("E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+ephi=sqrt(((((6350.853*0.8)+(26.243*0.6))^2)+(((6350.853*0.6)+(26.243*65.99))^2)))

+format(10)

+disp(ephi,"Therefore,  E_ph(in V) =")

+r=((7529.3113-6350.853)/6350.853)*100

+format(6)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

+disp("(b) cos(phi) = 0.9 leading,  sin(phi) = 0.4358, full load so I_aph = 52.486 A")

+disp("E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)-I_a*R_a)^2")

+ephi=sqrt(((((6350.853*0.9)+(52.486*0.6))^2)+(((6350.853*0.4358)-(52.486*65.99))^2)))

+format(9)

+disp(ephi,"Therefore,  E_ph(in V) =")

+r=((5789.231-6350.853)/6350.853)*100

+format(6)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

diff --git a/1370/CH4/EX4.2/Exp4_2.sce b/1370/CH4/EX4.2/Exp4_2.sce
new file mode 100755
index 000000000..8061b4013
--- /dev/null
+++ b/1370/CH4/EX4.2/Exp4_2.sce
@@ -0,0 +1,12 @@
+//Example 4.2

+clc

+n=36/4

+format(3)

+disp(n,"n = slots/pole =")

+beta=180/9

+disp(beta,"beta(in degree) = 180/n =")

+disp("Now coil is shorted by 1 slot i.e. by 20 to full pitch distance.")

+disp("Therefore,  alpha = Angle of short pitch = 20")

+kc=cosd(10)

+format(7)

+disp(kc,"Therefore,  K_c = cos(alpha/2) =")

diff --git a/1370/CH4/EX4.20/Exp4_20.sce b/1370/CH4/EX4.20/Exp4_20.sce
new file mode 100755
index 000000000..8ce134acb
--- /dev/null
+++ b/1370/CH4/EX4.20/Exp4_20.sce
@@ -0,0 +1,25 @@
+//Example 4.20

+clc

+disp("R_s = 0.6 ohm,  X_s = 6 ohm,  I_aph = 180 A")

+eph=6599/sqrt(3)

+format(10)

+disp(eph,"E_ph(in V) = E_line/sqrt(3) =")

+disp("(a) cos(phi) = 0.9 lagging, sin(phi) = 0.4358")

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+disp("Therefore,  (3809.9344)^2 = [V_ph*0.9 + 180*0.6]^2 + [V_ph*0.4358 + 180*6]^2")

+disp("Therefore,  14.5156*10^6 = 0.81*V_ph^2 + 194.4*V_ph + 11664 + 0.1899*V_ph^2 + 941.328*V_ph + 1166400")

+disp("Therefore,  V_ph^2 + 1135.728*V_ph - 13337536 = 0")

+disp("Therefore,  V_ph = 3128.08, -4263.808       ...Neglect negative value")

+disp("Therefore,  V_ph = 3128.08 V                  ...Terminal voltage")

+r=((3809.9344-3128.08)/3128.08)*100

+format(8)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

+disp("(b) cos(phi) = 0.8 leading, sin(phi) = 0.6")

+disp("Therefore,  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+disp("Therefore,  (3809.9344)^2 = [V_ph*0.8 + 180*0.6]^2 + [V_ph*0.6 + 180*6]^2")

+disp("Therefore,  14.5156*10^6 = 0.64*V_ph^2 + 172.8*V_ph + 11664 + 0.36*V_ph^2 - 1296*V_ph + 1166400")

+disp("Therefore,  V_ph^2 - 1123.2*V_ph - 13337536 = 0")

+disp("Therefore,  V_ph = 4256.5872 V       ...Neglect negative value")

+r=((3809.9344-4256.5872)/4256.5872)*100

+format(7)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

diff --git a/1370/CH4/EX4.21/Exp4_21.sce b/1370/CH4/EX4.21/Exp4_21.sce
new file mode 100755
index 000000000..f83622276
--- /dev/null
+++ b/1370/CH4/EX4.21/Exp4_21.sce
@@ -0,0 +1,29 @@
+//Example 4.21

+clc

+disp("1500 kVA,  V_L = 12 kV,  R_a = 2 ohm,  X_s = 10 ohm")

+vp=(12*10^3)/sqrt(3)

+format(10)

+disp(vp,"  V_ph(in V) =         ...Star")

+disp("P_L = sqrt(3)*V_L*I_L*cos(phi)")

+disp("(a) cos(phi) = 0.8 lagging,  sin(phi) = 0.6")

+il=(1200*10^3)/(sqrt(3)*0.8*12*10^3)

+format(7)

+disp(il,"Therefore,  I_L(in A) = I_aph =         ...Star")

+disp("  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+ephi=sqrt(((((6928.2032*0.8)+(72.168*2))^2)+(((6928.2032*0.6)+(72.168*10))^2)))

+format(9)

+disp(ephi,"Therefore,  E_ph(in V) =")

+r=((7492.768-6928.2032)/6928.2032)*100

+format(6)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

+disp("(b) cos(phi) = 0.707 leading,  sin(phi) = 0.707")

+il=(1200*10^3)/(sqrt(3)*0.707*12*10^3)

+format(6)

+disp(il,"Therefore,  I_L(in A) = I_a =         ...Star")

+disp("  E_ph^2 = (V_ph*cos(phi)+I_a*R_a)^2 + (V_ph*sin(phi)+I_a*R_a)^2")

+ephi=sqrt(((((6928.2032*0.707)+(81.66*2))^2)+(((6928.2032*0.707)-(81.66*10))^2)))

+format(10)

+disp(ephi,"Therefore,  E_ph(in V) =")

+r=((6502.2433-6928.2032)/6928.2032)*100

+format(6)

+disp(r,"Therefore,  %R(in percentage) = (E_ph-V_ph / V_ph)*100 = ")

diff --git a/1370/CH4/EX4.3/Exp4_3.sce b/1370/CH4/EX4.3/Exp4_3.sce
new file mode 100755
index 000000000..55b5e024b
--- /dev/null
+++ b/1370/CH4/EX4.3/Exp4_3.sce
@@ -0,0 +1,29 @@
+//Example 4.3

+clc

+disp("Ns = 250 r.p.m,  f = 50 Hz")

+disp("Ns = 120f / P")

+p=(120*50)/250

+disp(p,"Therefore,  P = ")

+n=216/24

+format(3)

+disp(n,"n = slots/pole =")

+m=9/3

+disp(m,"m = n/3 =")

+beta=180/9

+disp(beta,"beta(in degree) = 180/n =")

+kd=(sind(30)/(3*sind(10)))

+format(6)

+disp(kd,"Therefore,  K_d = sin(m*beta/2) / m*sin(beta/2) =")

+disp("K_c = 1 as full pitch coils.")

+z=216*5

+format(8)

+disp(z,"Total number of conductors Z = ")

+zph=1080/3

+disp(zph,"Therefore,  Z_ph = Z/3 =")

+tph=360/2

+disp(tph,"Therefore,  T_ph = Z_ph/2 =            ... 2 conductors constitute 1 turn")

+eph=4.44*0.9597*30*50*180*10^-3

+format(8)

+disp(eph,"E_ph(in V) = 4.44*Kc*Kd*f*phi*T_ph =")

+el=sqrt(3)*1150.48

+disp(el,"E_line(in V) = sqrt(3)*E_ph =           ...star connection")

diff --git a/1370/CH4/EX4.4/Exp4_4.sce b/1370/CH4/EX4.4/Exp4_4.sce
new file mode 100755
index 000000000..3ff1d775e
--- /dev/null
+++ b/1370/CH4/EX4.4/Exp4_4.sce
@@ -0,0 +1,27 @@
+//Example 4.4

+clc

+disp("E_line = 4000 V,  f = 50 Hz,  N_s = 750 r.p.m,  m = 3,  K_c = 1")

+eph=4000/sqrt(3)

+format(9)

+disp(eph,"E_ph(in V) = E_line/sqrt(3) =")

+p=(120*50)/750

+disp("(i) N_s = 120f / P")

+disp(p,"Therefore,  P =")

+disp("(ii) n = slots/pole = m*3 = 9")

+b=180/9

+disp(b,"beta = 180/n =")

+kd=sind(30)/(3*sind(10))

+format(7)

+disp(kd,"Therefore,  K_d = sin(m*beta/2) / m*sin(beta/2) =")

+ns=9*8

+disp(ns,"Number of slots = n * P =")

+z=72*12

+disp(z,"Z = Slots * counductors/slots =")

+zp=864/3

+disp(zp,"Therefore,  Z_ph = Z/3 =")

+tp=288/2

+disp(tp,"Therefore,  T_ph = Z_ph/2 =")

+phi=2309.401/(4.44*0.9598*50*144)

+format(8)

+disp("Therefore,  E_ph = 4.44*K_c*K_d*phi*f*T_ph")

+disp(phi,"Therefore,  phi(in Wb) =                  ... flux per pole")

diff --git a/1370/CH4/EX4.5/Exp4_5.sce b/1370/CH4/EX4.5/Exp4_5.sce
new file mode 100755
index 000000000..13abcfb02
--- /dev/null
+++ b/1370/CH4/EX4.5/Exp4_5.sce
@@ -0,0 +1,25 @@
+//Example 4.5

+clc

+disp("P = 100 kW,  cos(phi) = 0.8 lagging")

+disp("V_L = 11 kV,  R_a = 0.4 ohm,  X_s = 3 ohm")

+disp("For three phase load,  P = sqrt(3)*V_L*I_L*cos(phi)")

+il=(1000*10^3)/(sqrt(3)*11*0.8*10^3)

+format(5)

+disp(il,"Therefore,  I_L(in A) =")

+disp("Now  I_L = I_a as for star connected alternator I_L = I_ph")

+disp("Therefore,  I_aph = 65.6 A         ... full load per phase armature current")

+disp("For lagging p.f. loads,")

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

+vp=(11*10^3)/sqrt(3)

+format(9)

+disp(vp,"Now  V_ph = V_L / sqrt(3) =                 ... as star connected")

+eph=(((6350.853*0.8)+(65.6*0.4))^2)+(((6350.853*0.6)+(65.6*3))^2)

+p=sqrt(eph)

+format(8)

+disp(p,"Therefore,  E_ph(in V) = ")

+el=(sqrt(3)*6491.47)*10^-3

+format(6)

+disp(el,"Therefore,  E_line(in kV) =")

+regu=((6491.47-6350.853)/6350.853)*100

+disp(regu,"and  %Regulation(in percentage) = (E_ph-V_ph / V_ph)*100 =")

+disp("For lagging p.f. loads, regulation is always positive.")

diff --git a/1370/CH4/EX4.6/Exp4_6.sce b/1370/CH4/EX4.6/Exp4_6.sce
new file mode 100755
index 000000000..2ebc158f5
--- /dev/null
+++ b/1370/CH4/EX4.6/Exp4_6.sce
@@ -0,0 +1,31 @@
+//Example 4.6

+clc

+disp("kVA = 1200,  V_L = 6600 V,  R_a = 0.25 ohm,  X_s = 5 ohm")

+disp("Now  kVA = sqrt(3)*V_L*I_L*10^-3")

+il=1200/(sqrt(3)*6600*10^-3)

+format(7)

+disp(il,"Therefore,  I_L(in A) =")

+disp("Therefore,  I_aph = 104.97 A            ... as star connected.")

+disp("This is its full load current")

+vph=6600/sqrt(3)

+format(9)

+disp(vph,"  V_ph(in V) = V_L/3 =")

+disp("(i) For 0.8 lagging p.f. load")

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

+eph=(((3810.512*0.8)+(104.97*0.25))^2)+(((3810.512*0.6)+(104.97*5))^2)

+p=sqrt(eph)

+format(8)

+disp(p,"Therefore,  E_ph(in V) = ")

+regu=((4166.06-3810.512)/3810.512)*100

+format(5)

+disp(regu,"Therefore, %Regulation(in percentage) = (E_ph-V_ph / V_ph)*100 =")

+disp("(ii) For 0.8 leading p.f. load")

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

+eph=(((3810.512*0.8)+(104.97*0.25))^2)+(((3810.512*0.6)-(104.97*5))^2)

+p=sqrt(eph)

+format(8)

+disp(p,"Therefore,  E_ph(in V) = ")

+regu=((3543.47-3810.512)/3810.512)*100

+format(5)

+disp(regu,"Therefore, %Regulation(in percentage) = (E_ph-V_ph / V_ph)*100 =")

+disp("The regulation is negative for leading p.f. loads")

diff --git a/1370/CH4/EX4.7/Exp4_7.sce b/1370/CH4/EX4.7/Exp4_7.sce
new file mode 100755
index 000000000..6f736cac8
--- /dev/null
+++ b/1370/CH4/EX4.7/Exp4_7.sce
@@ -0,0 +1,41 @@
+//Example 4.7

+clc

+disp("V_L = 866 V,  kVA = 100")

+disp("Therefore,  kVA = sqrt(3)*V_L*I_L*10^-3")

+il=100/(sqrt(3)*866*10^-3)

+format(6)

+disp(il,"Therefore,  I_L(in A) =")

+disp("Therefore,  I_aph F.L. = I_L = 66.67 A              ... as star connected alternator")

+disp("V_ph = Rated terminal voltage per phase = V_L/3")

+vp=866/sqrt(3)

+disp(vp,"Therefore,  V_ph(in V) =")

+disp("For calculation of Z_s on full load, it is necessary to plot O.C.C. and S.C.C. to the scale")

+disp("Note :  If for same value of I_f, both I_ssc and V_oc can be obtained from the table itself, graph need not be plotted. In some problems, the values of V_oc and I_ssc for same I_f are directly given, in that case too, the graph need not be plotted.")

+disp("In this problem, I_ssc = 25 A for I_f = 1 A")

+disp("But we want to calculate Z_s for I_ssc = its full load value which is 66.67 A. So graph is required to be plotted.")

+disp("For plotting O.C.C. the lines values of open circuit voltage are converted to phase by dividing each value by sqrt(3)")

+disp("From S.C.C.")

+disp("For    I_scc = 66.67 A,  I_f = 2.4 A")

+disp("From O.C.C.")

+disp("For    I_f = 2.4 A,  (V_oc)_ph = 240 V")

+disp("From the graph, Z_s for full load is,")

+disp("Z_s = (V_oc)_ph / (I_scc)_ph |for same excitation")

+zs=240/66.67

+format(4)

+disp(zs,"Therefore,  Z_s(in ohm/phase) =")

+disp("R_a = 0.15 ohm/phase")

+xs=sqrt((3.6^2)-(0.15^2))

+format(6)

+disp(xs,"Therefore,  X_s(in ohm/phase) = sqrt(Z_s^2 - R_a^2) =")

+disp("V_ph F.L = 500 V")

+disp("cos(phi) = 0.8")

+disp("Therefore,  sin(phi) = 0.6 lagging p.f.")

+disp("So E_ph for full load, 0.8 lagging p.f. condition can be calculated as,")

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

+eph=(((500*0.8)+(66.67*0.15))^2)+(((500*0.6)+(66.67*3.597))^2)

+p=sqrt(eph)

+format(7)

+disp(p,"Therefore,  E_ph(in V) = ")

+regu=((677.86-500)/500)*100

+format(6)

+disp(regu,"Therefore, %Regulation(in percentage) = (E_ph-V_ph / V_ph)*100 =")

diff --git a/1370/CH4/EX4.8/Exp4_8.sce b/1370/CH4/EX4.8/Exp4_8.sce
new file mode 100755
index 000000000..fe30895fc
--- /dev/null
+++ b/1370/CH4/EX4.8/Exp4_8.sce
@@ -0,0 +1,43 @@
+//Example 4.8

+clc

+disp("V_L = 230 V,  R_a between lines = 1.8 ohm")

+disp("(V_oc)_line = 230 V,  I_scc = 12.5 A for same I_f = 0.38 A")

+disp("The value of open circuit e.m.f is always line value unless and until specifically mentioned to be a phase value")

+disp("Therefore,  Z_s = (V_oc)_ph / (I_scc)_ph |for same I_f")

+voc=230/sqrt(3)

+format(7)

+disp(voc,"  (V_oc)_ph(in V) =")

+zs=132.79/12.5

+disp(zs,"Therefore,  Z_s(in ohm/phase) =")

+disp("R_a between lines = 1.8 ohm")

+disp("For star connection, R_a between the terminals is 2 R_a per ph")

+disp("Therefore,  2R_a per ph = 1.8")

+disp("Therefore,  R_a per ph = 0.9 ohm")

+xs=sqrt((10.623^2)-(0.9^2))

+format(7)

+disp(xs,"Therefore,  X_s(in ohm/phase) = sqrt(Z_s^2 - R_a^2) =")

+disp("Now regulated is asked for I_a = 10 A")

+disp("Now :  The value of Z_s is calculated for I_s = 12.5 A and not at I_s = 10 A. It will be different for I_s = 10 A. But in this problem the test results are not given hence it is not possible to sketch the graphs to detemine Z_s at I_a = 10 A. So value of Z_s calculated is assumed to be same as I_a = 10 A")

+disp("(i) For 0.8 lagging p.f.")

+vph=230/sqrt(3)

+format(7)

+disp(vph,"V_ph(in V) = V_L/sqrt(3) =")

+disp("I_a = 10 A")

+disp("cos(phi) = 0.8    so sin(phi) = 0.6")

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

+eph=(((132.79*0.8)+(10*0.9))^2)+(((132.79*0.6)+(10*10.585))^2)

+p=sqrt(eph)

+format(8)

+disp(p,"Therefore,  E_ph(in V) = ")

+regu=((218.39-132.79)/132.79)*100

+format(6)

+disp(regu,"Therefore, %Regulation(in percentage) = (E_ph-V_ph / V_ph)*100 =")

+disp("(ii) For 0.8 leading p.f.")

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

+eph=(((132.79*0.8)+(10*0.9))^2)+(((132.79*0.6)-(10*10.585))^2)

+p=sqrt(eph)

+format(8)

+disp(p,"Therefore,  E_ph(in V) = ")

+regu=((118.168-132.79)/132.79)*100

+format(6)

+disp(regu,"Therefore, %Regulation(in percentage) = (E_ph-V_ph / V_ph)*100 =")

diff --git a/1370/CH4/EX4.9/Exp4_9.sce b/1370/CH4/EX4.9/Exp4_9.sce
new file mode 100755
index 000000000..f44cedef7
--- /dev/null
+++ b/1370/CH4/EX4.9/Exp4_9.sce
@@ -0,0 +1,29 @@
+//Example 4.9

+clc

+disp("P = 10,  N_a = 600 r.p.m,  slots = 90")

+disp("phi = 16 mWb,  E_line = 11 kW")

+f=6000/120

+format(3)

+disp("N_s = 120f / P")

+disp(f,"Therefore,  f(in Hz) =")

+eph=(11*10^3)/sqrt(3)

+format(9)

+disp(eph,"For star connection, E_ph(in V) = E_line/sqrt(3) =")

+disp("Now  E_ph = 4.44*K_c*K_d*phi*f*T_ph")

+disp("K_c = 1 as no information about short pitching is given")

+n=90/10

+disp(n,"n = slots/pole =")

+m=9/3

+disp(m,"m = slots/pole/phase = n/3 =")

+beta=180/9

+disp(beta,"beta = slot angle = 180/n =")

+kd=sind(30)/(3*sind(10))

+format(7)

+disp(kd,"Therefore,  K_d = sin(m*beta/2) / m*sin(beta/2) =")

+disp("Therefore,  6350.853 = 4.44*1*0.9598*16*10^-3*50*T_ph")

+tph=6350.853/(4.44*1*0.9598*16*50*10^-3)

+format(5)

+disp(tph,"Therefore,  T_ph =")

+zph=2*1862

+disp(zph,"Therefore,  Z_ph = 2*T_ph =")

+disp("These are armature conductors per phase required to be connected in series.")