1 files changed, 54 insertions, 0 deletions
diff --git a/3784/CH1/EX1.7/Ex1_7.sce b/3784/CH1/EX1.7/Ex1_7.sce
new file mode 100644
index 000000000..5d906c2e2
--- /dev/null
+++ b/3784/CH1/EX1.7/Ex1_7.sce
@@ -0,0 +1,54 @@
+clc
+// Variable Initialization 
+Vm=230 //Supply Voltage in Volts
+N=650//speed of motor in RPM
+I=100//Motor curent in Ampere
+Ra=0.08 //Armature circuit resistance in Ohm
+L=8e-3 //Armature circuit Inductance in mH
+V=230 //Ac Source voltage in Volts
+f=50 //source Frequency in Hz
+a=60
+aa=(60*%pi)/180 //in rad/sec
+a1=120
+aa1=(120*%pi)/180 //in rad/sec
+N2=400
+T=1000
+
+//Solution
+P=atand((2*%pi*f*L)/Ra) // In Degree
+Cot_P=1/(tand(P))
+A=exp(-%pi*Cot_P)
+B=exp((-aa)*Cot_P)
+Z=sqrt((Ra^2)+((2*%pi*f*L)^2)) //Impedance In Ohm
+Eb=Vm-(I*Ra) //back emf in Volts
+w=(2*%pi*N)/60 //Angular Speed in rad/sec
+K=Eb/w
+AA=(Ra*Vm*1.414)/(K*Z)
+Wmc=AA*((sind(P)*B)-(sind(a-P)*A))*(1/(1-A)) //Critical Speed in rad/Sec
+Wrpm=(Wmc*60)/(2*%pi) //speed in rpm
+//motor back emf for critical speed of 148 RPM
+Ec=(Wrpm*Eb)/N //Critical emf in Volts
+Va=(V*1.414)*(1+cosd(a))*(1/%pi) //Armature voltage in volts
+Tc=K*(Va-Ec)*(1/Ra) //Critical Torque in N-m
+//The check condition is
+Ia=T/K //Armature current in Amp
+Eb2=Va-(Ia*Ra) // Back emf in Volts
+Nm=(Eb2*N)/Eb//Motor speed in Rpm
+
+B1=exp((-aa1)*Cot_P)
+Wmc1=AA*((sind(P)*B1)-(sind(a1-P)*A))*(1/(1-A)) //Critical Speed in rad/Sec
+Wrpm1=(Wmc1*60)/(2*%pi) //speed in rpm
+//motor back emf for critical speed of 154 RPM
+Ec1=(Wrpm1*Eb)/N //Critical emf in Volts
+Va1=(V*1.414)*(1+cosd(a1))*(1/%pi) //Armature voltage in volts
+Tc1=K*(Va1-Ec1)*(1/Ra) //Critical Torque in N-m
+//The check condition is
+Ia1=-T/K //Armature current in Amp
+Eb3=Va1-(Ia1*Ra) // Back emf in Volts
+Nm1=(Eb3*N)/Eb//Motor speed in Rpm
+
+//Results
+printf('\n\n The motor Speed =%0.1f RPM \n\n',Nm)
+printf('\n\n The motor Speed =%0.1f RPM \n\n',Nm1)
+//The answers vary due to round off error(1st answer)
+