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9-16
L30 Line Current Differential System
GE Multilin
9.2 OPERATING CONDITION CHARACTERISTICS
9 THEORY OF OPERATION
9
9.2OPERATING CONDITION CHARACTERISTICS
9.2.1 DESCRIPTION
Characteristics of differential elements can be shown in the complex plane. The operating characteristics of the L30 are
fundamentally dependant on the relative ratios of the local and remote current phasor magnitudes and the angles of
/
as shown in the
Restraint Characteristics
figure.
The main factors affecting the trip-restraint decisions are:
1.
Difference in angles (+ real represents pure internal fault when currents are essentially in phase, – real represents
external fault when currents are 180° apart).
2.
The magnitude of remote current.
3.
The magnitude of the local current.
4.
Dynamically estimated errors in calculations.
5.
Settings.
The following figure also shows the relay's capability to handle week-infeed conditions by increasing the restraint ellipse
when the remote current is relatively small (1.5 pu). Therefore, uncertainty is greater when compared with higher remote
currents (3 pu). The characteristic shown is also dependant on settings. The second graph shows how the relay's trip-
restraint calculation is made with respect to the variation in angle difference between local and remote currents. The char-
acteristic for 3 terminal mode is similar where both remote currents are combined together.
I
loc
I
rem
Содержание L30
Страница 10: ...x L30 Line Current Differential System GE Multilin TABLE OF CONTENTS ...
Страница 30: ...1 20 L30 Line Current Differential System GE Multilin 1 5 USING THE RELAY 1 GETTING STARTED 1 ...
Страница 58: ...2 28 L30 Line Current Differential System GE Multilin 2 4 SPECIFICATIONS 2 PRODUCT DESCRIPTION 2 ...
Страница 126: ...4 30 L30 Line Current Differential System GE Multilin 4 3 FACEPLATE INTERFACE 4 HUMAN INTERFACES 4 ...
Страница 370: ...5 244 L30 Line Current Differential System GE Multilin 5 10 TESTING 5 SETTINGS 5 ...
Страница 396: ...6 26 L30 Line Current Differential System GE Multilin 6 5 PRODUCT INFORMATION 6 ACTUAL VALUES 6 ...
Страница 450: ...10 10 L30 Line Current Differential System GE Multilin 10 4 INSTANTANEOUS ELEMENTS 10 APPLICATION OF SETTINGS 10 ...
Страница 464: ...A 10 L30 Line Current Differential System GE Multilin A 1 PARAMETER LISTS APPENDIX A A ...
Страница 600: ...C 30 L30 Line Current Differential System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Страница 610: ...D 10 L30 Line Current Differential System GE Multilin D 1 IEC 60870 5 104 APPENDIX D D ...
Страница 622: ...E 12 L30 Line Current Differential System GE Multilin E 2 DNP POINT LISTS APPENDIX E E ...
Страница 634: ...F 12 L30 Line Current Differential System GE Multilin F 3 WARRANTY APPENDIX F F ...
Страница 644: ...x L30 Line Current Differential System GE Multilin INDEX ...