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186

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ELECTRICAL APPARATUS
_ 16,000 s2.

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10 8
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P
GENERAL Al
L 8000 s2

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_TE
1 + s2 ' 4000 s (5 + s) .

20,000 s(l - s)

1 + s2
RNATE CURRENT TRANSFORMER

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1

2.22.01.81.61.41.21.0.8 .6 .4 .2 0 .2 .1 .6 .8 1.0 1.2 1.4 1.01.8 2.0 2.2 2.4
FIG. 62.—Speed-power curves of general alternating-current transformer.
109. Since the most common practical application of the
general alternating-current transformer is that of frequency
converter, that is, to change from, one frequency to another,
either with or without change of the number of phases, the
following characteristic curves of this apparatus are of great
interest:
1. The regulation curve; that is, the change of secondary
terminal voltage as function of the load at constant impressed
primary voltage.