blob: 0a842586caa78e8c605c3e4a0bb3d8e716ea943a (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
// Electric Machinery and Transformers
// Irving L kosow
// Prentice Hall of India
// 2nd editiom
// Chapter 14: TRANSFORMERS
// Example 14-30
clear; clc; close; // Clear the work space and console.
// Given data
// subscripts a,b,c for the current, voltages indicates respective cases a ,b ,c.
// from fig.14-27a
V_pa = 1000 ; // Phase voltage in volt
I_1a = 1 ; // line current in primary in A
V_2a = 100 ; // voltage across secondary in V
Ic_a = 10 ; // current in lower half of auto-transformer in A
// from fig.14-26b
V_s = 100 ; // voltage in secondary wdg in V
I_2b = 10 ; // current in secondary in A
V_1b = 1000 ; // voltage across primary in V
Ic_b = 1 ; // current in lower half of auto-transformer in A
// Calculations
// case a
S_T1 = (V_pa*I_1a + V_2a*I_1a)/1000 ; // Total kVA transfer in step-down mode
// case b
S_T2 = (V_s*I_2b + V_1b*I_2b)/1000 ; // Total kVA transfer in step-up mode
// case c
S_x_former_c = V_pa*I_1a/1000 ; // kVA rating of th autotransformer in Fig.14-27a
// case d
V_1 = V_pa ;
S_x_former_d = V_1*Ic_b/1000 ; // kVA rating of th autotransformer in Fig.14-26b
// Display the results
disp("Example 14-30 Solution : ");
printf(" \n a: Total kVA transfer in step-down mode :\n S_T = %.1f kVA transferred \n",S_T1);
printf(" \n b: Total kVA transfer in step-up mode :\n S_T = %.1f kVA transferred \n",S_T2);
printf(" \n c: kVA rating of th autotransformer in Fig.14-27a:\n S_x-former = %d kVA \n ",S_x_former_c);
printf(" \n d: kVA rating of th autotransformer in Fig.14-26b:\n S_x-former = %d kVA \n ",S_x_former_d);
printf(" \n e: Both transformers have the same kVA rating of 1 kVA since the same ");
printf(" \n autotransformer is used in both parts.Both transformers transform ");
printf(" \n a total of 1 KVA. But the step-down transformer in part(a) conducts ");
printf(" \n only 0.1 kVA while the step-up transformer in the part(b) conducts 10");
printf(" \n kVA from the primary to the secondary.");
|
