GE Multilin
T35 Transformer Protection System
5-91
5 SETTINGS
5.4 SYSTEM SETUP
5
c) WINDINGS 1 TO 6
PATH: SETTINGS
SYSTEM SETUP
TRANSFORMER
WINDING 1(6)
The settings specific to each winding are shown above.
Transformer differential protection uses the following calculated quantities (per phase): fundamental, second harmonic, and
fifth harmonic differential current phasors, and restraint current phasors. This information is extracted from the current
transformers (CTs) connected to the relay by correcting the magnitude and phase relationships of the currents for each
winding, so as to obtain zero (or near zero) differential currents under normal operating conditions. Traditionally, these cor-
rections were accomplished by interposing CTs and tapped relay windings with some combination of CT connections.
The T35 simplifies these configuration issues. All CTs at the transformer are connected wye (polarity markings pointing
away from the transformer). User-entered settings in the relay characterizing the transformer being protected and allow the
relay to automatically perform all necessary magnitude, phase angle, and zero-sequence compensation.
This section describes the algorithms in the relay that perform this compensation and produce the required calculated
quantities for transformer differential protection, by means of the following example of a delta-wye (
Δ
-Y) connected power
transformer with the following data:
The abbreviated nomenclature for applicable relay settings is as follows:
Rotation
=
SETTINGS
SYSTEM SETUP
POWER SYSTEM
PHASE ROTATION
w
total
=
SETTINGS
SYSTEM SETUP
TRANSFORMER
GENERAL
NUMBER OF WINDINGS
Compensation
=
SETTINGS
SYSTEM SETUP
TRANSFORMER
GENERAL
PHASE COMPENSATION
Source [
w
]
=
SETTINGS
SYSTEM SETUP
TRANSFORMER
WINDING w
WINDING w SOURCE
WINDING 1
WINDING 1 SOURCE:
SRC 1
Range: SRC 1, SRC 2, SRC 3, SRC 4, SRC 5, SRC 6
(or the user-defined name)
MESSAGE
WINDING 1 RATED MVA:
100.000 MVA
Range: 0.001 to 2000.000 MVA in steps of 0.001
MESSAGE
WINDING 1 NOM
φ
-
φ
VOLTAGE: 220.000
kV
Range: 0.001 to 2000.000 kV in steps of 0.001
MESSAGE
WINDING 1
CONNECTION: Wye
Range: Wye, Delta, Zig-zag
MESSAGE
WINDING 1 GROUNDING:
Not within zone
Range: Not within zone, Within zone
MESSAGE
WINDING ~ ANGLE WRT
WINDING 1:
0.0°
Range: –359.9 to 0.0° in steps of 0.1, (‘~’ > 1)
(shown when viewed Winding is not Winding 1)
MESSAGE
WINDING 1 RESISTANCE
3
φ
: 10.0000
ohms
Range: 0.0001 to 100.0000 ohms in steps of 0.0001
Table 5–6: EXAMPLE DELTA-WYE CONNECTED POWER TRANSFORMER DATA
DATA
WINDING 1
Δ
(DELTA) CONNECTION
WINDING 2
Y (WYE) CONNECTION
Voltage Phasor Diagram
Phase Shift
0°
30° lag (i.e. phases of wye winding lag
corresponding phases of delta winding by 30°)
Grounding
In-zone grounding bank
Ungrounded
Rated MVA
100/133/166 MVA
100/133/166 MVA
Nominal
φ
-
φ
Voltage
220 kV
69 kV
CT Connection
Wye
Wye
CT Ratio
500/5
1500/5
Auxiliary Cooling
Two stages of forced air
Two stages of forced air
Summary of Contents for T35 UR Series
Page 10: ...x T35 Transformer Protection System GE Multilin TABLE OF CONTENTS ...
Page 48: ...2 18 T35 Transformer Protection System GE Multilin 2 2 SPECIFICATIONS 2 PRODUCT DESCRIPTION 2 ...
Page 314: ...5 192 T35 Transformer Protection System GE Multilin 5 10 TESTING 5 SETTINGS 5 ...
Page 338: ...6 24 T35 Transformer Protection System GE Multilin 6 5 PRODUCT INFORMATION 6 ACTUAL VALUES 6 ...
Page 350: ...7 12 T35 Transformer Protection System GE Multilin 7 2 TARGETS 7 COMMANDS AND TARGETS 7 ...
Page 366: ...8 16 T35 Transformer Protection System GE Multilin 8 2 CYBERSENTRY 8 SECURITY 8 ...
Page 406: ...A 14 T35 Transformer Protection System GE Multilin A 1 PARAMETER LISTS APPENDIX A A ...
Page 540: ...D 10 T35 Transformer Protection System GE Multilin D 1 IEC 60870 5 104 PROTOCOL APPENDIX D D ...
Page 552: ...E 12 T35 Transformer Protection System GE Multilin E 2 DNP POINT LISTS APPENDIX E E ...
Page 560: ...F 8 T35 Transformer Protection System GE Multilin F 3 WARRANTY APPENDIX F F ...