5-150
T35 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
SYSTEM SETUP
CHAPTER 5: SETTINGS
5
The settings specific to each winding are shown in the table.
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 corrections 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:
Table 5-18: Example of delta-wye connected power transformer 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
P
rated
[w] =
SETTINGS
SYSTEM SETUP
TRANSFORMER
WINDING w
WINDING w RATED MVA
V
nominal
[w] =
SETTINGS
SYSTEM SETUP
TRANSFORMER
WINDING w
WINDING w NOM F-F VOLTAGE
Connection [w] =
SETTINGS
SYSTEM SETUP
TRANSFORMER
WINDING w
WINDING w CONNECTION
WINDING 1
CONNECTION: Wye
Range: Wye, Delta, Zig-zag
WINDING 1 GROUNDING:
Not within zone
Range: Not within zone, Within zone
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)
WINDING 1 RESISTANCE
3
φ
: 10.0000 ohms
Range: 0.0001 to 100.0000 ohms in steps of 0.0001
The T35 is provided with this optional feature, specified as an option at the time of ordering. Using the order
code for your device, see the order codes in chapter 2 for details.
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
Содержание T35
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Страница 10: ...x T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL TABLE OF CONTENTS ...
Страница 14: ...1 4 T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL FOR FURTHER ASSISTANCE CHAPTER 1 INTRODUCTION 1 ...
Страница 202: ...4 88 T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL FLEXLOGIC DESIGN USING ENGINEER CHAPTER 4 INTERFACES 4 ...
Страница 472: ...5 270 T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL TESTING CHAPTER 5 SETTINGS 5 ...
Страница 500: ...6 28 T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL PRODUCT INFORMATION CHAPTER 6 ACTUAL VALUES 6 ...
Страница 514: ...7 14 T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL TARGETS MENU CHAPTER 7 COMMANDS AND TARGETS 7 ...
Страница 580: ...A 16 T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL FLEXANALOG ITEMS APPENDIX A FLEXANALOG OPERANDS A ...
Страница 588: ...C 6 T35 TRANSFORMER PROTECTION SYSTEM INSTRUCTION MANUAL COMMAND LINE INTERFACE APPENDIX C COMMAND LINE INTERFACE C ...
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