Tra
sformer
O
eofthemostvaluableapparatusi
electricpowersystemisthetra
sformerforite
ablesustoutilizediffere
tvoltagelevelsacrossthesystemforthemosteco
omicalvalueGe
eratio
ofpoweratthesy
chro
ousmachi
elevelis
ormallyatarelativelylowvoltage，whichismostdesirableeco
omically．Steppi
gupofthisge
eratedvoltagetohighvoltage，extrahighvoltageoreve
toultrahighvoltageisdo
ethroughpowertra
sformerstosuitthepowertra
smissio
requireme
ttomi
imizelossesa
di
creasethetra
smissio
capacityoftheli
es．Thistra
smissio
voltagelevelisthe
steppeddow
i
ma
ystagesfordistributio
a
dutilizatio
purposes．
Atra
sformerisastaticdevicefortra
sferri
gelectrice
ergyfromo
ecircuittoa
otherelectromag
etically，thatis，byi
ductio
i
steadofbyco
ductio
．Itsusualfu
ctio
istotra
sfere
ergybetwee
circuitsofdiffere
tvoltage．Atra
sformerhasamag
eticcoreo
whichtherearetwoormorewi
di
gs．Thesewi
di
gsarei
sulatedfromeachothera
dfromgrou
d．I
autotra
sformers，however，thewi
di
gsareco
ectedtogether．Theassemblyofcorea
dcoilsis
ormallyi
sulateda
dcooledbyimmersio
i
mi
eraloilorothersuitableliquidwithi
a
e
closi
gta
k．Co
ectio
tothewi
di
gsisbymea
sofi
sulati
gbushi
gs，usuallythroughthecover
The“ratiooftra
sformatio
”isdetermi
edbytherelative
umberoftur
si
eachofhewi
di
gs．Thisisk
ow
asthe“tur
ratio”a
ditistheratioofthe
f______________________________________________________________________________________________________________
oloadvoltages．Whe
theu
itiscarryi
gloadtheratiooftheactualvoltagesisslightlydiffere
tbecauseofthedropcausedbytheflowof1oadcurre
tthroughtheimpeda
ceofthetra
sformerwi
di
gs．Atratedloadthisdropisk
ow
asthe