diff options
Diffstat (limited to '3640/CH2')
| -rw-r--r-- | 3640/CH2/EX2.1/Ex2_1.sce | 12 | ||||
| -rw-r--r-- | 3640/CH2/EX2.10/Ex2_10.sce | 24 | ||||
| -rw-r--r-- | 3640/CH2/EX2.2/Ex2_2.sce | 26 | ||||
| -rw-r--r-- | 3640/CH2/EX2.3/Ex2_3.sce | 33 | ||||
| -rw-r--r-- | 3640/CH2/EX2.4/Ex2_4.sce | 21 | ||||
| -rw-r--r-- | 3640/CH2/EX2.5/Ex2_5.sce | 49 | ||||
| -rw-r--r-- | 3640/CH2/EX2.6/Ex2_6.sce | 27 | ||||
| -rw-r--r-- | 3640/CH2/EX2.7/Ex2_7.sce | 53 | ||||
| -rw-r--r-- | 3640/CH2/EX2.8/Ex2_8.sce | 25 |
9 files changed, 270 insertions, 0 deletions
diff --git a/3640/CH2/EX2.1/Ex2_1.sce b/3640/CH2/EX2.1/Ex2_1.sce new file mode 100644 index 000000000..f82ad5297 --- /dev/null +++ b/3640/CH2/EX2.1/Ex2_1.sce @@ -0,0 +1,12 @@ +clc
+L=0.25 //length of stator stack in metre
+r=0.15 //radius of stator stack in metres
+BImax=0.96 //peak value of air gap flux density in tesla
+P=6 //no of machine poles
+phi=(4*L*r*BImax)/P //flux per pole in webers
+mprintf("Φ=%fWb",phi)
+
+
+
+
+
diff --git a/3640/CH2/EX2.10/Ex2_10.sce b/3640/CH2/EX2.10/Ex2_10.sce new file mode 100644 index 000000000..4ecab79e6 --- /dev/null +++ b/3640/CH2/EX2.10/Ex2_10.sce @@ -0,0 +1,24 @@ +clc
+xd=1 //in ohms per unit
+xd1=0.3 //in ohms per unit
+xd2=0.2 //in ohms per unit
+Td2=0.03 //time in seconds
+Td1=1 //time in seconds
+MVA=100 //rating in mega volt ampere
+V=16000 //voltage in volts
+I2pu=1/xd2
+mprintf("Ipú́=%dper unit\n",I2pu)
+Ib=(MVA*(10^6))/(sqrt(3)*V)
+mprintf("Ib=%fA\n",Ib)//ans may vary due to roundoff error
+mprintf("Í́=%fA\n",I2pu*Ib)//ans in textbook is wrong
+I1=1/xd1 //current in per unit
+mprintf("Í=Efo/xd́=%fper unit\n",I1)//ans may vary due to roundoff error
+Iss=1/xd//current in per unit
+mprintf("Iss=Efo/xd=1 per unit\n")
+t=2/60 //time in seconds
+mprintf("I=%fper unit\n",(I2pu-I1)*exp(-t/Td2)+(I1-Iss)*exp(-t/Td1)+1)//ans may vary due to roundoff error
+t=10 //time in seconds
+mprintf("I=%fper unit\n",(I2pu-I1)*exp(-t/Td2)+(I1-Iss)*exp(-t/Td1)+1)//ans may vary due to roundoff error
+
+
+
diff --git a/3640/CH2/EX2.2/Ex2_2.sce b/3640/CH2/EX2.2/Ex2_2.sce new file mode 100644 index 000000000..16a6da638 --- /dev/null +++ b/3640/CH2/EX2.2/Ex2_2.sce @@ -0,0 +1,26 @@ +clc
+//the example below is an extension of Ex2_1
+L=0.25 //length of stator stack in metres
+r=0.15 //radius of stator stack in metres
+BImax=0.96 //peak value of air gap flux density in tesla
+P=6 //no of machine poles
+phi=(4*L*r*BImax)/P //flux per pole in webers
+//above comes from Ex2_1
+span=5 //span of each coil given by no of slots
+edps=30 //electrical degrees per slot in degrees
+p=span*edps//coil pitch in degrees
+mprintf("p=%d°\n",span*edps)
+Nc=2//turns of coil
+Kp=sin(((p/2)*%pi)/180) //pitch factor //degree being converted to radians before calculation
+mprintf("Kp=sin(p/2)=%f\n",Kp) //the ans may vary due to roundoff error
+mprintf("λcmax=Nc*Kp*Φ=%fWb turns\n",Nc*Kp*phi)//max flux linkage //ans may vary due to roundoff error
+ns=1000 //machine speed in rev/min
+p=6 //no of poles
+f=(p*ns)/120 //frequency at given speed in Hertz
+mprintf("f=%dHz\n",f)
+mprintf("Ec=sqrt(2)*Π*f*Nc*kp*Φ=%fV\n",sqrt(2)*%pi*f*Nc*Kp*phi)//ans may vary due to roundoff error //voltage induced at above frequency
+
+
+
+
+
diff --git a/3640/CH2/EX2.3/Ex2_3.sce b/3640/CH2/EX2.3/Ex2_3.sce new file mode 100644 index 000000000..f8b871ab4 --- /dev/null +++ b/3640/CH2/EX2.3/Ex2_3.sce @@ -0,0 +1,33 @@ +clc
+//the example below is an extension of Ex2_1 and Ex2_2
+S1=36 //no of slots
+q1=3 //no of phases
+p=6 //no of poles
+Nc=2 //no of turns per coil
+L=0.25 //length of stator stack in metres
+r=0.15 //radius of stator stack in metres
+BImax=0.96 //peak value of air gap flux density in tesla
+P=6 //no of machine poles
+phi=(4*L*r*BImax)/P //flux per pole in webers
+span=5 //span of each coil given by no of slots
+edps=30 //electrical degrees per slot in degrees
+p=span*edps//coil pitch in degrees
+Nc=2//turns of coil
+kp=sin(((p/2)*%pi)/180) //pitch factor //degree being converted to radians before calculation
+ns=1000 //machine speed in rev/min
+p=6 //no of poles
+f=(p*ns)/120 //frequency at given speed in Hertz
+Ec=sqrt(2)*%pi*f*Nc*kp*phi//voltage induced at above frequency
+n=S1/(q1*p)
+mprintf("n=S1/(q1*p)=%f\n",n) //coils per group
+edps=30 //electrical degrees per slot //equal to γ as per textbook
+kd=(sin((n*edps*%pi)/(180*2)))/(n*sin((edps/2)*%pi/180)) //distribution factor of the machine //degree converted to radian for calculation
+mprintf("kd=sin(n*γ/2)/n*sin(γ/2)=%f\n",kd)//ans may vary due to roundoff error
+mprintf("|Egroup|=n*Ec*kd=%fV\n",n*Ec*kd)//ans may vary due to roundoff error
+mprintf("|EΦ|=p*|Egroup|=%fV\n",p*n*Ec*kd)//ans may vary due to roundoff error
+mprintf("sqrt(3)*EΦ=%dV\n",sqrt(3)*n*Ec*kd*p)//ans may vary due to roundoff error
+stp=n*Nc*p //series turns per phase //equal to NΦ in textbook
+mprintf("NΦ=n*Nc*p=%dturns\n",stp)
+mprintf("|EΦ|=sqrt(2)*Π*NΦ*f*Φ*kp*kd=%fV",sqrt(2)*%pi*stp*f*kp*kd*phi) //ans may vary due to round off error //induced phase winding
+
+
diff --git a/3640/CH2/EX2.4/Ex2_4.sce b/3640/CH2/EX2.4/Ex2_4.sce new file mode 100644 index 000000000..331ae2e95 --- /dev/null +++ b/3640/CH2/EX2.4/Ex2_4.sce @@ -0,0 +1,21 @@ +clc
+Vl=2300 //terminal voltage of synchronous motor in volts
+Il=8.8 //minimum line current in ampere
+P=sqrt(3)*Vl*Il
+mprintf("P=%fKW\n",P/1000)//power drawn from the line //ans may vary due to round off error
+pf=0.8 //operating power factor
+mprintf("HP=P/746=%fhp\n",P/746)//ans may vary due to round off error //conversion of power to hp requires division by 746
+S=P/(pf*1000) //total volt amperes of motor in kVA
+mprintf("Q=|S|sinθΦm=|S|sin cos-1(pf)=%fkVAR",S*sin(acos(pf))) //kVAR supplied by motor to the system //ans may vary due to roundoff error
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/3640/CH2/EX2.5/Ex2_5.sce b/3640/CH2/EX2.5/Ex2_5.sce new file mode 100644 index 000000000..d73ae2672 --- /dev/null +++ b/3640/CH2/EX2.5/Ex2_5.sce @@ -0,0 +1,49 @@ +clc
+//the following code contains userdefined fucntion complexstring
+function s=complexstring(a)
+
+ if imag(a)>=0 then
+ s=sprintf('%g+%gi',real(a),imag(a))
+ else
+ s=sprintf('%g%gi',real(a),imag(a))
+
+ end
+ funcprot(0)
+endfunction
+Load=5000 //load of the plant in kW
+pf1=0.8 //power factor of load(lagging)
+pf2=0.9 //power factor of induction motor
+pf3=0.8 //power factor of synchronous motor
+Hp=500 //rating of induction motor to be replaced in hp
+Pout=0.746*Hp //output power of induction motor in kW
+Eta=0.96 //efficiency of the induction motor equal to η in textbook
+Sp=Load+(Load*tan(acos(pf1)))*%i //original complex power of load in kVA
+disp('Sp=' + complexstring(Sp)+'kVA')
+Pin=Pout/Eta //input power in kW
+mprintf("Pin=%fkW\n",Pin)//complex power of induction motor //the ans may vary due to round off error
+Sm=Pin+(Pin*tan(acos(pf2)))*%i
+disp('Sm='+complexstring(Sm)+'kVA')//the ans may vary due to round off error //complex power of induction motor
+mprintf("\n")
+Ss=Pin-(Pin*tan(acos(pf3)))*%i
+disp('Ss='+complexstring(Ss)+'kVA')//complex power of synchronous machine //the ans may vary due to round off error
+mprintf("\n")
+Qm=(Pin*tan(acos(pf2)))*%i//reactive power of induction motor in kVAR
+Qs=(-1*(Pin*tan(acos(pf3)))*%i)//reactive power of synchronous motor in kVAR
+Sp1=Sp-Qm+Qs
+disp('Sp1='+complexstring(Sp1)+'kVA')//new plant requirement,equal to Sp` in textbook
+mprintf("\n")
+pha=acos(real(Sp1)/abs(Sp1)) //phase angle of Sp1 in radians
+mprintf("New power factor=%f\n",cos(pha))//new power factor //the ans may vary due to round off error
+invl=abs(Sp)//initial value of complex power in kVA
+fnvl=abs(Sp1) //final value of complex power in kVA
+mprintf("Percent reduction=%f%c\n",(((invl-fnvl)/invl)*100),'%')//the ans may vary due to round off error
+
+
+
+
+
+
+
+
+
+
diff --git a/3640/CH2/EX2.6/Ex2_6.sce b/3640/CH2/EX2.6/Ex2_6.sce new file mode 100644 index 000000000..92eef7758 --- /dev/null +++ b/3640/CH2/EX2.6/Ex2_6.sce @@ -0,0 +1,27 @@ +clc
+//the example below is an extension of Ex2_5
+//the following code contains userdefined fucntion complexstring
+function s=complexstring(a)
+
+ if imag(a)>=0 then
+ s=sprintf('%g+%gi',real(a),imag(a))
+ else
+ s=sprintf('%g%gi',real(a),imag(a))
+
+ end
+ funcprot(0)
+endfunction
+Load=5000 //load of the plant in kW
+pf1=0.8 //power factor of load(lagging)
+Sp=Load+(Load*tan(acos(pf1)))*%i //original complex power of load in kVA
+disp('Sp='+complexstring(Sp)+'kVA')
+pf2=0.9 //new power factor
+Qp1=real(Sp)*tan(acos(0.9)) //reactive power,equal to Qp` in textbook
+mprintf("Qp`=%fkVAR\n",Qp1)//the ans vary due to roundoff error
+Qp=imag(Sp)
+mprintf("Qs=%fkVAR",Qp1-Qp)//KVAR to be supplied by synchronous condenser
+
+
+
+
+
diff --git a/3640/CH2/EX2.7/Ex2_7.sce b/3640/CH2/EX2.7/Ex2_7.sce new file mode 100644 index 000000000..4de784cbb --- /dev/null +++ b/3640/CH2/EX2.7/Ex2_7.sce @@ -0,0 +1,53 @@ +clc
+
+//the code below uses userdefined complexstring function
+function s=complexstring(a)
+
+
+ if imag(a)>=0 then
+ s=sprintf('%g+%gi',real(a),imag(a))
+ else
+ s=sprintf('%g%gi',real(a),imag(a))
+
+ end
+ funcprot(0)
+endfunction
+VLB=2400 //line to base voltage in volts
+V1=VLB/sqrt(3) //reference phasor in volts //ans may vary due to roundoff error
+mprintf("V1=%fV\n",V1)
+kVAB=9375 //rated kVA
+I1B=(kVAB*1000)/(sqrt(3)*VLB)
+pf=0.8 //power factor
+mprintf("I1B=%fA\n",I1B) //ans may vary due to roundoff error
+I1=I1B*exp((-1)*%i*(acos(pf)))
+disp('I1='+complexstring(I1)+'A')//ans may vary due to roundoff error
+mprintf("\n")
+x1=0.1//in ohms
+disp('EΦ=V1+jI1x1='+complexstring(V1+%i*I1*x1)+'V')//ans may vary due to roundoff error
+mprintf("\n")
+disp('sqrt3*|EΦ|='+complexstring((abs(V1+%i*I1*x1))*sqrt(3))+'V')
+Ifu=110 //value in ampere,dc
+Ifs=149 //value in ampere,dc
+ks=Ifs/Ifu
+mprintf("ks=%f\n",ks) //ans may vary due to roundoff error
+m1=(abs((V1+%i*I1*x1)))/Ifs //equal to m` in textbook
+mprintf("ḿ́=|EΦ|/Ifs=%fΩ\n",m1)//ans may vary due to roundoff error
+xdu=0.8 //in ohms
+xd=x1+((xdu-x1)/ks)
+mprintf("xd=x1+(xdu-x1)/ks=%fΩ\n",xd)//ans may vary due to roundoff error
+Ef=V1+(%i*I1*xd)
+disp('Ef='+complexstring(Ef)+'V')//ans may vary due to roundoff error
+mprintf("\n")
+mprintf("If=%fA\n",abs(Ef)/m1)//ans may vary due to roundoff error
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/3640/CH2/EX2.8/Ex2_8.sce b/3640/CH2/EX2.8/Ex2_8.sce new file mode 100644 index 000000000..52b925862 --- /dev/null +++ b/3640/CH2/EX2.8/Ex2_8.sce @@ -0,0 +1,25 @@ +clc +VLB=2400 //line to base voltage in volts +Ix=2005 //current in amperes +xda=VLB/(sqrt(3)*Ix) +mprintf("xda=%fΩ\n",xda)//ans may vary due to roundoff error +Ifv=116 //current in amperes +ma1=VLB/(sqrt(3)*Ifv)//equal to ma` in textbook +mprintf("má=V1B/Ifv=%fΩ\n",ma1)//ans may vary due to roundoff error +//from ex 2_7 +V1=VLB/sqrt(3) //reference phasor in volts +kVAB=9375 //rated kVA +I1B=(kVAB*1000)/(sqrt(3)*VLB)//current in amperes +pf=0.8 //power factor +I1=I1B*exp((-1)*%i*(acos(pf)))//current in amperes +Ef=V1+%i*I1*xda +disp('Ef='+string(Ef)+'V')//ans may vary due to roundoff error +mprintf("If=|Ef|/má=%fA\n",abs(Ef)/ma1)//ans may vary due to roundoff error +Voc=2960 //line to line volatge in Volts +mprintf("V1oc=%fV\n",Voc/sqrt(3))//ans may vary due to roundoff error +If=240 //current in amperes +Efmax=ma1*If +mprintf("Efmax=%dV\n",Efmax)//ans in textbook is wrong +I1max=(Efmax-V1)/xda //ans in textbook is wrong +mprintf("I1max=%fA\n",I1max)//ans may vary due to roundoff error +mprintf("Qmax=%fMVAR",sqrt(3)*VLB*I1max*(10^-6))//ans may vary due to roundoff error
\ No newline at end of file |