initial commit / add all books

6 files changed, 162 insertions, 0 deletions

diff --git a/1319/CH7/EX7.1/7_1.sce b/1319/CH7/EX7.1/7_1.sce
new file mode 100644
index 000000000..68b3e0b17
--- /dev/null
+++ b/1319/CH7/EX7.1/7_1.sce
@@ -0,0 +1,19 @@
+//Power delivered to 3 phase synchronous motor 

+

+clc;

+clear;

+

+Vl=2300;

+Il=8.8;

+pf=0.8// Lead Power Factor

+theta=acosd(pf)

+

+P=sqrt(3)*Vl*Il; // Power delivered by the pump

+

+I=P/(sqrt(3)*Vl*pf); // Increase in Current

+

+Pr=sqrt(3)*Vl*I*sind(theta); // kVAr supplied

+

+printf('The Power delivered by the pump = %g kW \n',P/1000)

+printf('The Rheostat should be decreased such that the ammeter reads %g A \n',I)

+printf('The kVAr supplied by the motor = %g kVAr',Pr/1000)

diff --git a/1319/CH7/EX7.2/7_2.sce b/1319/CH7/EX7.2/7_2.sce
new file mode 100644
index 000000000..8f65ab20c
--- /dev/null
+++ b/1319/CH7/EX7.2/7_2.sce
@@ -0,0 +1,44 @@
+//New plant pf and percent decrease in line current

+

+clc;

+clear;

+

+Pmp=5000*(10^3); // Electrical load

+pfmp=0.8; // Lag

+

+Pim=500*735;// One horse power is 735W

+Effim=96/100; // Efficiency of the motor

+pfim=0.9; // Lag

+pfsm=0.8; // Lead

+

+Pime=Pim/Effim;// Effective power delivered by the induction motor

+

+deff('x=com(y,z)','x=y+(%i*y*tand(acosd(z)))')// Function to find the complex powers

+

+//Complex Powers

+Pcmp=com(Pmp,pfmp); // Manufacturing Plant Load

+Pcim=com(Pime,pfim);// Induction Motor

+Pcsm=com(Pime,-pfsm);// Synchronous Machine, Minus Sign indicates Lead

+

+Pr=Pcmp-Pcim+Pcsm; // Plant Requirement after replacement

+

+pfar=real(Pr)/abs(Pr); // New Power Factor of the plant

+

+Pnp=abs(Pr);

+

+Vl=poly([0 1],'Vl','c');

+

+Io=Pmp/(pfmp*sqrt(3)*Vl);

+In=Pnp/(sqrt(3)*Vl); // Improved Factor Value =1;

+

+red=(Io-In)*100/Io; // Reduction percent in fractions

+

+redeq=Vl-red;// Reduction percent in decimal characteristic equation 

+

+redper=roots(redeq(2));

+

+printf('The New Power Factor of the plant = %g lag \n',pfar )

+printf('The Percentage decrease in line current that will result in improved p.f = %g percent \n',redper)

+

+

+

diff --git a/1319/CH7/EX7.3/7_3.sce b/1319/CH7/EX7.3/7_3.sce
new file mode 100644
index 000000000..1fb843214
--- /dev/null
+++ b/1319/CH7/EX7.3/7_3.sce
@@ -0,0 +1,14 @@
+//kVAr rating of a synchronous condenser

+

+clc;

+clear;

+

+P=5000*(10^3); // Power delivered to the load

+pfo=0.8;// Original Power Factor

+pfn=0.9;// New Power Factor

+Pcomo=P+%i*(P*tand(acosd(pfo)));//Original Complex Power

+Pcomn=P+%i*(P*tand(acosd(pfn)));//New Complex Power

+

+Psc=abs(imag(Pcomo-Pcomn)); // Difference in kVAr;

+

+printf('The kVAr rating of the synchronous condenser to correct the original p.f to 0.9 = %g kVAr \n',Psc/1000)

diff --git a/1319/CH7/EX7.4/7_4.sce b/1319/CH7/EX7.4/7_4.sce
new file mode 100644
index 000000000..1049d83c4
--- /dev/null
+++ b/1319/CH7/EX7.4/7_4.sce
@@ -0,0 +1,34 @@
+//Calculate E per phase and Current and pf

+

+clc;

+clear;

+

+V=2300;

+delta=20;

+Pd=255*735.5; // Power delivered converted to W from HP

+Xs=10;

+eff=90/100; //Efficiency

+

+P=Pd/eff;

+

+E=poly([0 1],'E','c');

+

+x=(sqrt(3)*E*V*sind(delta))-(P*Xs); // Characteristic Equation to find E

+

+E=roots(x);

+

+Vph=V/(sqrt(3));// Phase Voltage

+

+I=((Vph*expm(%i*0))-(E*expm(%i*(-%pi/9))))/(%i*Xs);// Current Eqaution

+

+[Im,phi]=polar(I); // Angle in radians and magnitude

+

+phid=(abs(phi)/%pi)*180;// Power Factor Angle in Degrees

+

+pf=cosd(phid);

+

+// High Precision Answers

+printf('a) E per phase = %g V \n',E)

+disp('amperes',I,'b) I =')

+printf('\n c) p.f = %g lead \n',pf)

+

diff --git a/1319/CH7/EX7.5/7_5.sce b/1319/CH7/EX7.5/7_5.sce
new file mode 100644
index 000000000..eb839751a
--- /dev/null
+++ b/1319/CH7/EX7.5/7_5.sce
@@ -0,0 +1,34 @@
+//Voltage Regulation of a 3 Phase alternator

+

+clc;

+clear;

+

+Ra=0.093;

+Xs=8.5;

+Z=(Ra+(%i*Xs)); // Total Impedance

+

+P=1500*(10^3); // Power delivered at full load

+V=6.6*(10^3); // Voltage per line

+Vph=V/(sqrt(3)); // Voltage per phase

+

+Il=P/(sqrt(3)*V); // Full Load Current

+

+

+// Taking voltage as reference

+//Power Angles

+theta1=-acos(0.8); // Negative Sign as It is lagging

+theta2=acos(0.8); 

+

+deff('a=pot(b)','a=Vph+((Il*expm(%i*b))*Z)')// Function to find out the output phase voltage

+

+E1=pot(theta1);

+E2=pot(theta2);

+

+deff('y=vg(x)','y=(abs(x)-Vph)*100/Vph') // Function to find out the voltage regulation using the formuala

+

+Vreg1=vg(E1);

+Vreg2=vg(E2);

+

+printf('The Voltage regulation of a 3-Phase 1500 kVA, 6.6 kV alternator at \n')

+printf('i) 0.8 lag = %g percent \n',Vreg1)

+printf('ii) 0.8 lead = %g percent \n',Vreg2)

diff --git a/1319/CH7/EX7.6/7_6.sce b/1319/CH7/EX7.6/7_6.sce
new file mode 100644
index 000000000..5a0d89d3a
--- /dev/null
+++ b/1319/CH7/EX7.6/7_6.sce
@@ -0,0 +1,17 @@
+// Internal Voltage drop in an alternator

+

+clc;

+clear;

+

+If=10;

+Voc=900; // Open Circuit Voltage

+

+Isc=150; // Short Circuit Current

+

+Zs=Voc/Isc;

+

+I=60; // Load current

+

+Vd=I*Zs; // Internal Voltage Drop

+

+printf('The internal voltage drop with a load current of 60 A = %g V \n',Vd)