ELEMENTS OF
ELECTRICAL
ENGINEERING
THREE PHASED
BALANCED SYSTEMS
Shreya Paid
, FORMULAS
Balanced star =
Balanced delta :
IL=Iph IL = V3 Iph
vi. =D Vpn V2 -
-
Vpn
Vlllhds Vpn IL tags Iph by 30
'
by 30
'
Vph Iphttl
-
-
Power :
-
Active power (D)
=
3
Iphvphcoscf =
V3 Ichabod
P =
312pm R
-
Reactive power ④ =
3 Vphtsphsin D= V3 VIII. Sino
CVARORKVAR) D= 3IpKXL or
8=-3 Iptt Xc
Apparent powers ] 3VphIph
=
VZVLIL =
3IpklZl
-
=
CVA or KVA)
S=dÑp2
* Wattmeter :
Inductor :
Ni =
KIL cos (30+01) capacitive :
W, _-
vi. Ilcos ③0-47
WE WIL Cos (30-4) wz= HIM (30+4)
Wltwz =
Pret = NJ Viscuso
V3 ( w -
wz)= duet =
VJVLIL Sino
,
tano-anet-r.IE?g)-ne coso- cos-'(tan- '
'
cost tan
/ @ Cw;÷w )))
wso =
,
•
If we orwz = -
ve cos of < 0.5
•
If W , & Wz = the cos of 70-5
Cos of 0
If
=
W
Wz 0
•
, or =
•
If ↳
=
Wz cost = I
?⃝
ELECTRICAL
ENGINEERING
THREE PHASED
BALANCED SYSTEMS
Shreya Paid
, FORMULAS
Balanced star =
Balanced delta :
IL=Iph IL = V3 Iph
vi. =D Vpn V2 -
-
Vpn
Vlllhds Vpn IL tags Iph by 30
'
by 30
'
Vph Iphttl
-
-
Power :
-
Active power (D)
=
3
Iphvphcoscf =
V3 Ichabod
P =
312pm R
-
Reactive power ④ =
3 Vphtsphsin D= V3 VIII. Sino
CVARORKVAR) D= 3IpKXL or
8=-3 Iptt Xc
Apparent powers ] 3VphIph
=
VZVLIL =
3IpklZl
-
=
CVA or KVA)
S=dÑp2
* Wattmeter :
Inductor :
Ni =
KIL cos (30+01) capacitive :
W, _-
vi. Ilcos ③0-47
WE WIL Cos (30-4) wz= HIM (30+4)
Wltwz =
Pret = NJ Viscuso
V3 ( w -
wz)= duet =
VJVLIL Sino
,
tano-anet-r.IE?g)-ne coso- cos-'(tan- '
'
cost tan
/ @ Cw;÷w )))
wso =
,
•
If we orwz = -
ve cos of < 0.5
•
If W , & Wz = the cos of 70-5
Cos of 0
If
=
W
Wz 0
•
, or =
•
If ↳
=
Wz cost = I
?⃝
