Electric Power Generation, Transmission, and Distribution

(Tina Meador) #1
fAAP¼
m 0
2 p

IAln
DAP
GMRA


ðÞWb=m (13:41)

fABP¼
m 0
2 p

IBln
DBP
DAB


ðÞWb=m (13:42)

fACP¼
m 0
2 p

ICln
DCP
DAC


ðÞWb=m (13:43)

The corresponding flux linkage of conductor A at pointP(Fig. 13.12) is evaluated as


lAP¼lAAPþlABPþlACP (13:44)

having


lAAP¼

m 0
2 p
IAln

DAP
GMRA


ðÞWb=m (13:45)

A B C

fA f (^) B f (^) C
DAB DBC
DCA
X X X
FIGURE 13.11 Magnetic flux produced by each conductor in a three-phase system.
C
DAP
B
P
lAAP
lABP lACP
PP
DAC
DAP DAP DCP
DBP
A A
B B
C C
(a) (b) (c)
A
DAB
FIGURE 13.12 Flux linkage of (a) conductor A at pointP, (b) conductor B on conductor A at pointP, and (c)
conductor C on conductor A at pointP. Three-phase system.

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