Download Chapter 1_ 3PS: Connection

THREE PHASE SYSTEM
CONNECTION
 There are TWO types of connection:
i. STAR connection
ii. DELTA connection
 Each of this connection is differ in
terms of relationship between
voltage or current.
 This connection is connected to both
LOAD and SOURCE.
(1) STAR CONNECTION
a) Star Connection-Three Wire:
OR
b) Star Connection-Four Wire
OR
Y-Y Analysis
a
A
Z1a
IA
Z ga
n
Va 'n


ZA
I0

 
Vc 'n
N
Z0
b
Z gb
B
Z1b
ZB
IB
Vb 'n

ZC
Z gc
c
C
Z1c
IC
Single Phase equivalent circuit
(a phase as a reference)
a
Va 'n
a
'
Zga


n
A
Z1a
ZA
Line Voltage Source in Star
Connection
Phase Voltage Source in Star
Connection
STAR CONNECTION IN BALANCED
SYSTEM
Secara
umumnya,
In general,
VA  VB  VC dan I A  I B  I C
Line Voltage
Voltan
Talian , VL : V AB , V BC , V CA
Voltan
fasa , Vp
Vf
Phase Voltage
: V AN , V BN , V CN
ArusTalian
fasa ,Ip
If : IA , IB , IC
Line Current, I L  Arus
Phase Current
RELATIONSHIP BETWEEN PHASE
VOLTAGE AND LINE VOLTAGE
a) POSITIVE SEQUENCE, ABC
b) NEGATIVE SEQUENCE, ACB
Line Voltage in Star Connection
a) POSITIVE SEQUENCE
By consider phase voltage VAN as a
reference;
VAN  VAN0
volt
VBN  VAN  120 volt
VCN  VAN120
volt
Line Voltage AB can be accomplished as
follows:
V AB  V AN  V NB
 V AN  V BN
 VAN0  VAN  120
 VAN  VAN  0.5  j0.866 
 1.5VAN  j0.866VAN
 1.732VAN30

3 VAN30
volt
Line Voltage BC can be
accomplished as follows:
V BC  V BN  V CN
 VAN  120  VAN120
 VAN  0.5  j0.866  VAN  0.5  j0.866
 VAN  j1.732
 3 VAN  90 volt
Line Voltage CA can be
accomplished as follows:
V CA  V CN  V AN
 VAN120  VAN
 VAN  0.5  j0.866  1
 VAN  1.5  j0.866
 1.732 VAN150
 3 VAN150
volt
VAN  VAN0
volt
VBN  VAN  120 volt
VCN  VAN120 volt
LINE
VOLTAGE
PHASE
VOLTAGE
VAB  3 VAN30 volt
VBC  3 VAN  90 volt
VCA  3 VAN150 volt
PHASOR DIAGRAM VL, VP POSITIVE
SEQUENCE
VCN
VCA
VAB
30º
120º
30º
120º
30º
VBN
VBC
120º
VAN
POSITIVE SEQUENCE
CHARACTERISTICS:
a) Line Voltage, VL is √3 phase voltage,Vf
:
 VL  3 Vp
b) Line Voltage, VL LEADING phase
voltage, Vp by 30º;
c) Line Current, IL is equal to phase
current, Ip :
 I L  Ip
b) NEGATIVE SEQUENCE
By consider the phase voltage VAN as
a reference;
VAN  VAN0
volt
VBN  VAN120
volt
VCN  VAN  120 volt
Line Voltage AB can be
accomplished as follow:
V AB  V AN  V NB
 V AN  V BN
 VAN 0  VAN 120
 VAN  VAN  0.5  j0.866 
 1.5VAN  j0.866 VAN
 1.732 VAN   30

3 VAN   30
volt
Line Voltage BC can be
accomplished as follows:
V BC  V BN  V CN
 VAN120  VAN  120
 VAN  0.5  j0.866  VAN  0.5  j0.866
 VAN  j1.732
 3 VAN90 volt
Line Voltage CA can be
accomplished as follows:
V CA  V CN  V AN
 VAN   120  VAN
 VAN  0.5  j0.866  1
 VAN  1.5  j0.866 
 1.732 VAN   150

3 VAN   150
volt
VAN  VAN0
volt
VBN  VAN120 volt
PHASE
VOLTAGE
VCN  VAN  120 volt
LINE
VOLTAGE
VAC  3 VAN  30 volt
VAB  3 VAN90 volt
VBC  3 VAN  150 volt
PHASOR DIAGRAM VL, VP NEGATIVE
SEQUENCE
VBC
VBN
30º
120º
120º
30º
30º
VAN
120º
VAB
VCA
VCN
NEGATIVE SEQUENCE
CHARACTERISTICS:
a) Line Voltage, VL is √3 phase
voltage,Vp :
 VL  3 Vp
b) Line Voltage, VL LAGGING phase
voltage,Vp by 30º;
c) Line Current, IL is equal to phase
current, Ip :
 I L  Ip
(2) DELTA-CONNECTION
OR
Phase Current in Delta Connection
Line Current in Delta Connection
BALANCE SYSTEM IN DELTACONNECTION
In general,
Line Voltage VL  PhaseVolta ge, Vp
 V AB, V BC , V CA
LineCurren t, I L  I A , I B , I C
PhaseCurre nt , I p  I AB, I BC , I CA
RELATIONSHIP BETWEEN PHASE CURRENT
AND LINE CURRENT
a) POSITIVE SEQUENCE, ABC
b) NEGATIVE SEQUENCE, ACB
Line Current/Voltage in Delta Connection
(a) POSITIVE SEQUENCE
By considered phase current IAB as a
reference;
I AB  I AB0
A
I BC  I AB  120 A
I CA  I AB120
A
Line Current A can be accomplished
as follow:
I A  I AB  I CA
 I AB  I AB120
 I AB 1   0.5  j0.866 
 I AB 1.5  j0.866 
 1.732 I AB  30

3 I AB  30
A
Line Current B can be accomplished as
follow:
I B  I BC  I AB
 I AB  120  I AB
 I AB  0.5  j0.866  1
 I AB  1.5  j0.866 
 1.732 I AB  150

3 I AB  150
A
Line Current C can be accomplished
as follow:
I C  I CA  I BC
 I AB120  I AB  120
 I AB  0.5  j0.866    0.5  j0.866 
 I AB  j1.732 
 1.732 I AB90
 3 I AB90 A
I AB  I AB0
A
I BC  I AB  120 A
I CA  I AB120 A
LINE
CURRENT
PHASE
CURRENT
I A  3 I AB  30 A
I B  3 I AB  150 A
I C  3 I AB90 A
PHASOR DIAGRAM IL, Ip POSITIVE
SEQUENCE
IC
ICA
30º
120º
120º
30º
IB
IBC
30º
120º
IAB
IA
POSITIVE SEQUENCE
CHARACTERISTICS:
a) Line current, IL is √3 phase
current,Ip :
 I L  3 Ip
b) Line current, IL LAGGING phase
current,Ip by 30º;
c) Line Voltage, VL is equal to phase
voltage, Vp :
 VL  Vp
(b) NEGATIVE SEQUENCE
By considered phase current IAB as a
reference;
I AB  I AB0
volt
I BC  VAB120 volt
I CA  VAB  120
volt
Line Current A can be accomplished
as follow:
I A  I AB  I CA
 I AB  I AB  120
 I AB 1   0.5  j0.866 
 I AB 1.5  j0.866 
 1.732 I AB30

3 I AB30
A
Line current B can be accomplished
as follow:
I B  I BC  I AB
 I AB120  I AB
 I AB  0.5  j0.866  1
 I AB  1.5  j0.866 
 1.732 I AB150

3 I AB150
A
Line Current C can be accomplished
as follow:
I C  I CA  I BC
 I AB  120  I AB120
 I AB  0.5  j0.866    0.5  j0.866 
 I AB  j1.732 
 1.732 I AB  90
 3 I AB  90
A
I AB  I AB0
A
I BC  I AB  120 A
I CA  I AB120 A
LINE
CURRENT
PHASE
CURRENT
I A  3 I AB30 A
I B  3 I AB150 A
I C  3 I AB  90A
PHASOR DIAGRAM IL, Ip NEGATIVE
SEQUENCE
IB
IBC
IA
120º
30º
30º
120º
30º
ICA
IC
120º
IAB
NEGATIVE SEQUENCE
CHARACTERISTICS:
a) Line current, IL is √3 phase
current,Ip :
 I L  3 Ip
b) Line current, IL LEADING phase
current,Ip by 30º;
c) Line Voltage, VL is equal to phase
Voltage, Vp :
 VL  Vp
CONNECTION TYPES
Source
Load
Connection
Star
Star
Y-Y
Star
Delta
Y-
Delta
Delta
- 
Delta
Star
-Y