
System condition
Permissive channel
received
Loss of guard
Permissive
trip allowed
Alarm
generated
Unblock
No
Yes
Yes, during a 150 ms
window
Yes, delayed on pickup by
150 ms
Signalling Anomaly
Yes
No
No
Yes, delayed on pickup by
150 ms
The window of time during which the unblocking logic is enabled starts 10ms after the guard signal is lost, and
continues for 150ms. The 10ms delay gives time for the signalling equipment to change frequency, as in normal
operation. For the duration of any alarm condition, Zone 1 extension logic is invoked if the Z1 Ext Scheme setting is
set to operate for channel failure.
4.4
CURRENT REVERSAL GUARD LOGIC
For double circuit lines, the fault current direction can change in one circuit when circuit breakers open
sequentially to clear the fault on the parallel circuit. The change in current direction causes the overreaching
distance elements to see the fault in the opposite direction to the direction in which the fault was initially detected
(settings of these elements exceed 150% of the line impedance at each terminal). The race between operation and
resetting of the overreaching distance elements at each line terminal can cause permissive overreach, and
blocking schemes to trip the healthy line. A system configuration that could result in current reversals is shown in
the figure below. For a fault on line L1 close to circuit breaker B, as circuit breaker B trips it causes the direction of
current flow in line L2 to reverse. Current reversal guard logic is incorporated in this product to prevent POR and
Blocking schemes from tripping incorrectly during current reversal conditions.
E03503
Strong
source
Fault
Weak
source
Fault
Note how after circuit breaker B on line L1 opens
the direction of current flow in line L2 is reversed.
A
C
L2
D
B
L1
t2(C)
t2(D)
A
C
L2
D
B
L1
Figure 73: Example of fault current reversal of direction
The current reversal guard incorporated in the permissive overreach scheme logic is initiated when the reverse
looking Zone 4 elements operate on a healthy line.
Once the reverse looking Zone 4 elements have operated, the permissive trip logic and signal send logic are
inhibited at substation D. The reset of the current reversal guard timer is initiated when the reverse looking Zone 4
resets. A time delay tReversal Guard is required in case the overreaching trip element at end D operates before
the signal send from the protection at end C has reset. Otherwise this would cause the product at D to overreach.
Permissive tripping for the products at D and C substations is enabled again once the faulted line is isolated and
the current reversal guard time has expired.
The current reversal guard incorporated in the blocking scheme logic is initiated when a blocking element picks-up
to inhibit the channel-aided trip. When the current reverses and the reverse looking Zone 4 elements reset, the
blocking signal is maintained by the timer tReversal Guard. Therefore, the protections in the healthy line are
prevented from overreaching due to the sequential opening of the circuit breakers in the faulted line. After the
faulted line is isolated, the reverse-looking Zone 4 elements at substation C and the forward looking elements at
substation D reset.
Chapter 8 - Carrier Aided Schemes
P446SV
176
P446SV-TM-EN-1
Содержание MiCOM P40 Agile
Страница 2: ......
Страница 24: ...Contents P446SV xxii P446SV TM EN 1 ...
Страница 33: ...CHAPTER 1 INTRODUCTION ...
Страница 34: ...Chapter 1 Introduction P446SV 2 P446SV TM EN 1 ...
Страница 46: ...Chapter 1 Introduction P446SV 14 P446SV TM EN 1 ...
Страница 47: ...CHAPTER 2 SAFETY INFORMATION ...
Страница 48: ...Chapter 2 Safety Information P446SV 16 P446SV TM EN 1 ...
Страница 60: ...Chapter 2 Safety Information P446SV 28 P446SV TM EN 1 ...
Страница 61: ...CHAPTER 3 HARDWARE DESIGN ...
Страница 62: ...Chapter 3 Hardware Design P446SV 30 P446SV TM EN 1 ...
Страница 88: ...Chapter 3 Hardware Design P446SV 56 P446SV TM EN 1 ...
Страница 89: ...CHAPTER 4 SOFTWARE DESIGN ...
Страница 90: ...Chapter 4 Software Design P446SV 58 P446SV TM EN 1 ...
Страница 101: ...CHAPTER 5 CONFIGURATION ...
Страница 102: ...Chapter 5 Configuration P446SV 70 P446SV TM EN 1 ...
Страница 124: ...Chapter 5 Configuration P446SV 92 P446SV TM EN 1 ...
Страница 125: ...CHAPTER 6 SAMPLED VALUE OPERATION ...
Страница 126: ...Chapter 6 Sampled Value Operation P446SV 94 P446SV TM EN 1 ...
Страница 136: ...Chapter 6 Sampled Value Operation P446SV 104 P446SV TM EN 1 ...
Страница 137: ...CHAPTER 7 DISTANCE PROTECTION ...
Страница 138: ...Chapter 7 Distance Protection P446SV 106 P446SV TM EN 1 ...
Страница 196: ...Chapter 7 Distance Protection P446SV 164 P446SV TM EN 1 ...
Страница 197: ...CHAPTER 8 CARRIER AIDED SCHEMES ...
Страница 198: ...Chapter 8 Carrier Aided Schemes P446SV 166 P446SV TM EN 1 ...
Страница 240: ...Chapter 8 Carrier Aided Schemes P446SV 208 P446SV TM EN 1 ...
Страница 241: ...CHAPTER 9 NON AIDED SCHEMES ...
Страница 242: ...Chapter 9 Non Aided Schemes P446SV 210 P446SV TM EN 1 ...
Страница 256: ...Chapter 9 Non Aided Schemes P446SV 224 P446SV TM EN 1 ...
Страница 257: ...CHAPTER 10 POWER SWING FUNCTIONS ...
Страница 258: ...Chapter 10 Power Swing Functions P446SV 226 P446SV TM EN 1 ...
Страница 281: ...CHAPTER 11 AUTORECLOSE ...
Страница 282: ...Chapter 11 Autoreclose P446SV 250 P446SV TM EN 1 ...
Страница 376: ...Chapter 11 Autoreclose P446SV 344 P446SV TM EN 1 ...
Страница 377: ...CHAPTER 12 CB FAIL PROTECTION ...
Страница 378: ...Chapter 12 CB Fail Protection P446SV 346 P446SV TM EN 1 ...
Страница 389: ...CHAPTER 13 CURRENT PROTECTION FUNCTIONS ...
Страница 390: ...Chapter 13 Current Protection Functions P446SV 358 P446SV TM EN 1 ...
Страница 416: ...Chapter 13 Current Protection Functions P446SV 384 P446SV TM EN 1 ...
Страница 417: ...CHAPTER 14 VOLTAGE PROTECTION FUNCTIONS ...
Страница 418: ...Chapter 14 Voltage Protection Functions P446SV 386 P446SV TM EN 1 ...
Страница 431: ...CHAPTER 15 FREQUENCY PROTECTION FUNCTIONS ...
Страница 432: ...Chapter 15 Frequency Protection Functions P446SV 400 P446SV TM EN 1 ...
Страница 438: ...Chapter 15 Frequency Protection Functions P446SV 406 P446SV TM EN 1 ...
Страница 439: ...CHAPTER 16 MONITORING AND CONTROL ...
Страница 440: ...Chapter 16 Monitoring and Control P446SV 408 P446SV TM EN 1 ...
Страница 476: ...Chapter 16 Monitoring and Control P446SV 444 P446SV TM EN 1 ...
Страница 477: ...CHAPTER 17 SUPERVISION ...
Страница 478: ...Chapter 17 Supervision P446SV 446 P446SV TM EN 1 ...
Страница 490: ...Chapter 17 Supervision P446SV 458 P446SV TM EN 1 ...
Страница 491: ...CHAPTER 18 DIGITAL I O AND PSL CONFIGURATION ...
Страница 492: ...Chapter 18 Digital I O and PSL Configuration P446SV 460 P446SV TM EN 1 ...
Страница 504: ...Chapter 18 Digital I O and PSL Configuration P446SV 472 P446SV TM EN 1 ...
Страница 505: ...CHAPTER 19 FIBRE TELEPROTECTION ...
Страница 506: ...Chapter 19 Fibre Teleprotection P446SV 474 P446SV TM EN 1 ...
Страница 522: ...Chapter 19 Fibre Teleprotection P446SV 490 P446SV TM EN 1 ...
Страница 523: ...CHAPTER 20 ELECTRICAL TELEPROTECTION ...
Страница 524: ...Chapter 20 Electrical Teleprotection P446SV 492 P446SV TM EN 1 ...
Страница 534: ...Chapter 20 Electrical Teleprotection P446SV 502 P446SV TM EN 1 ...
Страница 535: ...CHAPTER 21 COMMUNICATIONS ...
Страница 536: ...Chapter 21 Communications P446SV 504 P446SV TM EN 1 ...
Страница 606: ...Chapter 21 Communications P446SV 574 P446SV TM EN 1 ...
Страница 607: ...CHAPTER 22 CYBER SECURITY ...
Страница 608: ...Chapter 22 Cyber Security P446SV 576 P446SV TM EN 1 ...
Страница 625: ...CHAPTER 23 INSTALLATION ...
Страница 626: ...Chapter 23 Installation P446SV 594 P446SV TM EN 1 ...
Страница 637: ...CHAPTER 24 COMMISSIONING INSTRUCTIONS ...
Страница 638: ...Chapter 24 Commissioning Instructions P446SV 606 P446SV TM EN 1 ...
Страница 695: ...CHAPTER 25 MAINTENANCE AND TROUBLESHOOTING ...
Страница 696: ...Chapter 25 Maintenance and Troubleshooting P446SV 664 P446SV TM EN 1 ...
Страница 712: ...Chapter 25 Maintenance and Troubleshooting P446SV 680 P446SV TM EN 1 ...
Страница 713: ...CHAPTER 26 TECHNICAL SPECIFICATIONS ...
Страница 714: ...Chapter 26 Technical Specifications P446SV 682 P446SV TM EN 1 ...
Страница 741: ...APPENDIX A ORDERING OPTIONS ...
Страница 742: ...Appendix A Ordering Options P446SV P446SV TM EN 1 ...
Страница 744: ...Appendix A Ordering Options P446SV A2 P446SV TM EN 1 ...
Страница 745: ...APPENDIX B SETTINGS AND SIGNALS ...
Страница 746: ...Appendix B Settings and Signals P446SV P446SV TM EN 1 ...
Страница 954: ...Appendix B Settings and Signals P446SV B208 P446SV TM EN 1 ...
Страница 955: ...APPENDIX C WIRING DIAGRAMS ...
Страница 956: ...Appendix C Wiring Diagrams P446SV P446SV TM EN 1 ...
Страница 960: ......
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