From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 1092/CH8/EX8.20/Example8_20.sce | 56 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100755 1092/CH8/EX8.20/Example8_20.sce

(limited to '1092/CH8/EX8.20')

diff --git a/1092/CH8/EX8.20/Example8_20.sce b/1092/CH8/EX8.20/Example8_20.sce
new file mode 100755
index 000000000..1d5154286
--- /dev/null
+++ b/1092/CH8/EX8.20/Example8_20.sce
@@ -0,0 +1,56 @@
+// Electric Machinery and Transformers
+// Irving L kosow 
+// Prentice Hall of India
+// 2nd editiom
+
+// Chapter 8: AC DYNAMO TORQUE RELATIONS - SYNCHRONOUS MOTORS
+// Example 8-20
+
+clear; clc; close; // Clear the work space and console.
+
+// Given data
+f_a = 400 ; // Frequency of the alternator in Hz
+f_m = 60 ; // Frequency of the motor in Hz
+
+// Calculations
+Pole_ratio = f_a / f_m ; // Ratio of no. of poles in alternator to that of motor
+// Subscript 1 below indicates 1st combination
+P_a1 = 40 ; // first combination must have 40 poles on the alternator
+P_m1 = 6 ; // first combination must have 6 poles on the synchronous motor at a speed
+S_m1 = (120*f_m) / P_m1 ; // Speed of the motor in rpm
+
+// Subscript 2 below indicates 2nd combination
+P_a2 = 80 ; // second combination must have 40 poles on the alternator
+P_m2 = 12 ; // second combination must have 12 poles on the synchronous motor at a speed
+S_m2 = (120*f_m) / P_m2 ; // Speed of the motor in rpm
+
+// Subscript 13below indicates 3rd combination
+P_a3 = 120 ; // third combination must have 40 poles on the alternator
+P_m3 = 18 ; // third combination must have 18 poles on the synchronous motor at a speed
+S_m3 = (120*f_m) / P_m3 ; // Speed of the motor in rpm
+
+// Display the result
+disp("Example 8-20 Solution : ");
+
+printf(" \n Since P_a/P_m = f_a/f_m = %d/%d, or %d/%d, the ratio of",f_a,f_m,f_a/20,f_m/20);
+printf(" \n f_a/f_m determines the combinations of poles and speed.\n");
+printf(" \n Only even multiples of the above ratio are possible,since poles ");
+printf(" \n are always in pairs, hence first three combinations are as follows \n");
+
+printf(" \n The first combination must have %d poles on the alternator and ",P_a1);
+printf(" \n %d poles on the sychronous motor at a speed = %d rpm.\n",P_m1,S_m1);
+
+printf(" \n The second combination must have %d poles on the alternator and ",P_a2);
+printf(" \n %d poles on the sychronous motor at a speed = %d rpm.\n",P_m2,S_m2);
+
+printf(" \n The third combination must have %d poles on the alternator and ",P_a3);
+printf(" \n %d poles on the sychronous motor at a speed = %d rpm.\n",P_m3,S_m3);
+
+printf(" \n ___________________________________________________________________");
+printf(" \n Combination \t  Alternator Poles \t  Motor Poles \t Speed (rpm)");
+printf(" \n             \t         P_a       \t      P_m      \t     S      ");
+printf(" \n ___________________________________________________________________");
+printf(" \n First \t\t:\t  %d\t\t       %d \t    %d",P_a1,P_m1,S_m1);
+printf(" \n Second\t\t:\t  %d\t\t       %d \t    %d",P_a2,P_m2,S_m2);
+printf(" \n Third \t\t:\t  %d\t\t       %d \t    %d",P_a3,P_m3,S_m3);
+printf(" \n ___________________________________________________________________");
-- 
cgit