summaryrefslogtreecommitdiff
path: root/3731/CH5/EX5.16/Ex5_16.sce
diff options
context:
space:
mode:
Diffstat (limited to '3731/CH5/EX5.16/Ex5_16.sce')
-rw-r--r--3731/CH5/EX5.16/Ex5_16.sce62
1 files changed, 62 insertions, 0 deletions
diff --git a/3731/CH5/EX5.16/Ex5_16.sce b/3731/CH5/EX5.16/Ex5_16.sce
new file mode 100644
index 000000000..3e7e9948f
--- /dev/null
+++ b/3731/CH5/EX5.16/Ex5_16.sce
@@ -0,0 +1,62 @@
+//Chapter 5:Dc Motor Drives
+//Example 16
+clc;
+
+//Variable Initialization
+
+//Ratings of the separately excited motor
+V=220 // rated voltage in v
+N=960 // rated speed in rpm
+Ia=12.8 // rated current in A
+Ra=2 // armature resistance in ohms
+Vs=230 // source voltage in v
+f=50 //frequency of the source voltage in hz
+La=150e-3 // armature curcuit inductance in H
+
+//Solution
+E=V-Ia*Ra //back emf
+Vm=sqrt(2)*Vs //peak voltage
+Wm=2*%pi*N/60 //angular speed
+W=2*%pi*f
+
+//(i)When speed is 600rpm and the firing angle is 60 degrees
+alpha=60 //firing angle in degrees
+N1=600 //motor speed in rpm
+x=W*La/Ra
+phi=atan(x)
+cot_phi=1/tan(phi)
+Z=sqrt(Ra**2+(W*La)**2)
+K=E/Wm
+
+y=Ra*Vm/Z/K
+alpha=alpha*%pi/180
+b=sin(phi)*exp(-(alpha*cot_phi))
+c=sin(alpha-phi)*exp(-(%pi*cot_phi))
+a=1-exp(-(%pi*cot_phi))
+Wmc=y*(b-c)/a //required angular speed in rps
+Nmc=Wmc*60/2/%pi //required angular speed in rpm
+
+Va=Vm/%pi*(1+cos(alpha))
+E1=N1/N*E //value of back emf at the speed of N1
+Ia=(Va-E1)/Ra
+T=K*Ia
+
+//(ii)When the torque is 20 N-m and firing angle is 60 degrees
+T1=20 //required torque in N-m
+alpha=60 //required firing angle in degrees
+Ec=Nmc/N*E //motor back emf at critical speed of Nmc
+Tc=K*(Va-Ec)/Ra //torque at the critical speed
+
+Ia=T1/K
+E1=Va-Ia*Ra
+N1=E1/E*N //required speed
+
+//Results
+//if N1<Nmc then
+mprintf("(i)The motor is operating under continuous condition")
+mprintf("\nHence the required torque is :%.2f N-m",T)
+//end
+//if Tc<T1 then
+mprintf("\n(ii)The motor is operating under continuous condition")
+mprintf("\nHence the required speed is :%.1f rpm",N1)
+//end