Page 51 - Electrical Equipment Handbook _ Troubleshooting and Maintenance

TRANSFORMERS

3.8 CHAPTER THREE

[(0.0018 j0.0024) (4 j3)]
5.003 36.88°

Notice that Z″ 4 j3 and Z line 0.0018 j0.0024 . The resulting equivalent
load
circuit is shown in Fig. 3.5b. The generator’s current is
480 0° V
I 95.94 36.88° A
G
5.003 36.88°
Knowing the current I , we can now work back and find I line and I load . Working back
G
through T , we get
1
N I N I
P 1 G S 1 line
N
P 1
I I
line N G
S 1
1
⁄10(95.94 36.88° A)
9.594 36.88° A

FIGURE 3.5 (a) System with the load referred to the transmission system voltage level. (b) System
with the load and transmission line referred to the generator’s voltage level.

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