diff options
Diffstat (limited to '1319/CH8/EX8.5')
-rw-r--r-- | 1319/CH8/EX8.5/8_5.sce | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/1319/CH8/EX8.5/8_5.sce b/1319/CH8/EX8.5/8_5.sce new file mode 100644 index 000000000..0a2915010 --- /dev/null +++ b/1319/CH8/EX8.5/8_5.sce @@ -0,0 +1,39 @@ +//Tapping of an auto transformer to limit current in squirrel cage motor
+
+clc;
+clear;
+
+V=400; // Line to line voltage
+Vph=V/sqrt(3); // Phase voltage
+Z=1.54; // Standstill impedance
+Ifl=30;// Full Load Current
+Imax=75; // Max current which can be taken by the line
+s=4/100; // Full load slip
+
+t=poly([0 1],'t','c'); // Variable for tapping percent of normal voltage
+
+Is=t*(Vph/(100*Z)); // Starting current in the motor
+
+Ias=(t/100)*Is; // Current on supply side of the auto transformer
+
+Tap=Ias-Imax; // Equation to find t
+
+t=roots(Tap);// Numerical Value for t
+
+if(imag(sqrt(t(1))))
+ t=t(2);
+else
+ t=t(1);
+end
+
+
+Ism=Imax*100/t; // Starting current in the motor (Numerical Value)
+
+st=((Ism/Ifl)^2)*s; // Starting torque to full load torque ratio
+
+printf('The tapping provided to the auto transformer = %g percent of Normal Voltage \n',t)
+
+printf('The starting torque available is %g times the full load torque \n',st)
+
+
+
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