PERSOALAN SISTEM 3 SEIMBANG (SIMETRIS)
ANALISA SISTEM TENAGA LISTRIK I
PERSOALAN SISTEM 3 ( SEIMBANG (SIMETRIS)Diketahui: Diagram
segaris sistem 3 ( seimbang seperti gambar di bawah ini. Daya aktif
beban 3 ( sebesar 18 KW, faktor daya beban 0,83 lagging, tegangan
line beban 1,2 KV, masing-masing saluran mempunyai impedansi 2 +j
1,5 (.
Ditanya: a. Hitung besar arus fasa masing-masing beban, besar
tegangan fasa masing-masing beban,
besar impedansi fasa masing-masing beban.
b. Hitung besar arus fasa sumber, tegangan fasa sumber, tegangan
line sumber, daya 3 (
sumber
c. Gambar pasor diagram: tegangan fasa sumber, tegangan line
sumber dan arus line sumber. Penyelesaian:
Besar beban 1( :
P1 ( = = 6000 watt
Tegangan fasa beban:
Va,n, = = 692,82(0o volt
Vb,n, = 692,82(-120o volt
Vc,n, = 692,82(-240o voltArus fasa beban:
Ia,n, = = = 10,434(-33,9o amper
Ib,n, = 10,434(-153,9o amper
Ic,n, = 10,434(-273,9o amper
Di dalam hubungan Y:
Arus fasa beban = arus line = arus fasa sumber, maka:
Ia,n, = Ia = Ian, sehingga arus fasa sumber:
Ian = 10,434(-33,9o amper
Ibn = 10,434(-153,9o amper
Icn = 10,434(-273,9o amper
Impedansi fasa masing-masing beban:
Za = = 66,4(33,9o = 55,11 + j 37,034 (
Zb = = 66,4(33,9o = 55,11 + j 37,034 (
Zc = = 66,4(33,9o = 55,11 + j 37,034 ( Tegangan fasa sumber:
Van = Va,n, + (Ia,n,. ZL) = 692,82(0o + {(10,434(-33,9o)(2 + j
1,5)}
= 692,82(0o + {(8,66 j 5,82)(2 + j 1,5)}
= 692,82 + (8,59 + j 1,35) = 701,41 + j1,35
= 701,21(0,1103o volt
Vbn = 701,21(-119,8897o volt
Vcn = 701,21(-239,8897o volt
Tegangan line sumber:
Vab = . Van. 30o = (701,21(0,1094o). 30o = 1214,53 (30,1094o
volt
Vbc = . Vbn. 30o = . 701,21(-119,89o. 30o = 1214,53 (-89,8906o
volt
Vca = . Vcn. 30o = . 701,21(-239,89o. 30o = 1214,53 (-209,8906o
voltDaya 3 ( sumber:
S3( = 3 { ( V ( ( I ( cos ( + j ( V ( ( I ( sin ( }
= 3 {(701,21)(10,434) 0,83 + j (701,21)(10,434) 0,5577}
= 18217.9 + j 12241.11 VA
Gambar phasor diagram 3 ( seimbang
Selamat Bekerja
GATOT WIDODO, TEKNIK ELEKTRO, UNESA
_1328435383.unknown
_1328439489.unknown
_1328442297.unknown
_1455607335.vsda
b
n
c
a
b
c
n
2 + j 1,5 ohm
2 + j 1,5 ohm
2 + j 1,5 ohm
_1455609379.vsdVab
Van
Ian
Vbc
Vbn
Ibn
Icn
Vca
Vcn
_1328439672.unknown
_1328442226.unknown
_1328439182.unknown
_1328433981.unknown
_1328435277.unknown
_1328433861.unknown
