P746/EN AP/G31
Application Notes
(AP) 6-
8
MiCOM
P746
AP
2.2.1.1.1 Sub-station features
Only 8 values have to be known:
1.
Number of independent bars
2.
Maximum number of infeeds
3.
Minimum load current in a feeder
4.
Maximum load current in a feeder
5.
Maximum load current in a bus
6.
Biggest CT primary winding
7.
Minimum short-circuit value (phase to phase) in a bus
8.
Voltage used (Yes or No)
2.2.1.1.2 “Idiff_Ibias” Setting calculation spreadsheet
Enter in the Idiff_Ibias spreadsheet the 8 values here above listed and you’ll be able to
choose the 7 values hereafter listed.
It is important to know that if the minimum internal fault detection is set below the maximum
load an additional criterion such as voltage must be used.
2.2.1.1.3 Differential Busbar Protection
1.
ID>1 as high as possible with a minimum of 2% of the biggest CT primary winding and
less than 80% of the minimum load
2.
Slope k1 (ID>1), usual recommendation is 10%
3.
ID>2 as low as possible*, whilst ensuring the single CT failure will not cause tripping
under maximum load conditions with no VT.
4.
Slope k2 (ID>2), usuaL recommendation is generally 50 / 65%
5.
IDCZ>2 as low as possible*
6.
Slope kCZ (IDCZ>2), usual recommendation is generally 30%
Explanations of the values:
1. ID>1 shall be higher than 2% of the biggest CT to not detect noise coming from it and
less than 80% of the minimum load of a feeder to detect the minimum load imbalance in
case of a problem in that particular feeder.
2. Slope k1 recommendation is 10% to meet 10Pxx current transformers
3. ID>2
shall
be:
•
below twice the maximum load for the phase comparison algorithm to pickup the
load and if possible below 50% of the minimum fault to be sub-cycle (80%
otherwise)
•
and if no voltage criteria is used above 100% (and when possible 120% to allow
20% margin) of the biggest load to not maloperate in case of CT short-circuited or
open circuit
Note: voltage criteria can be used for single busbar only in one box mode.
•
and less than 80% of the minimum fault current to operate sub-cycle for the
minimum fault (and 50% when possible to be sure to always operate in 13ms)
Summary of Contents for MiCOM P746
Page 4: ......
Page 5: ...Pxxx EN SS G11 SAFETY SECTION...
Page 6: ......
Page 8: ...Pxxx EN SS G11 Page 2 8 Safety Section BLANK PAGE...
Page 16: ...P746 EN IT G31 Introduction MiCOM P746...
Page 18: ...P746 EN IT G31 Introduction IT 1 2 MiCOM P746 IT BLANK PAGE...
Page 26: ...P746 EN TD G31 Technical Data MiCOM P746...
Page 38: ...P746 EN GS G31 Getting Started MiCOM P746...
Page 78: ...P746 EN ST G31 Getting Started MiCOM P746...
Page 80: ...P746 EN ST G31 Settings ST 4 2 MiCOM P746 ST BLANK PAGE...
Page 112: ...P746 EN ST G31 Settings ST 4 34 MiCOM P746 ST BLANK PAGE...
Page 114: ...P746 EN OP G31 Operation MiCOM P746...
Page 136: ...P746 EN OP G31 Operation OP 5 22 MiCOM P746 OP BLANK PAGE...
Page 138: ...P746 EN AP G31 Application Notes MiCOM P746...
Page 142: ...P746 EN AP G31 Application Notes AP 6 4 MiCOM P746 AP BLANK PAGE...
Page 194: ...P746 EN AP G31 Application Notes AP 6 56 MiCOM P746 AP BLANK PAGE...
Page 196: ...P746 EN PL G31 Programmable Logic MiCOM P746...
Page 238: ...P746 EN MR A11 Measurements and Recording MiCOM P746...
Page 240: ...P746 EN MR A11 Measurements and Recording MR 8 2 MiCOM P746 MR BLANK PAGE...
Page 258: ...P746 EN FD G31 Firmware Design MiCOM P746...
Page 280: ......
Page 348: ...P746 EN MT A11 Maintenance MiCOM P746...
Page 350: ...P746 EN MT A11 Maintenance MT 11 2 MiCOM P746 MT BLANK PAGE...
Page 364: ...P746 EN MT A11 Maintenance MT 11 16 MiCOM P746 MT BLANK PAGE...
Page 366: ...P746 EN TS G31 Troubleshooting MiCOM P746...
Page 368: ...P746 EN TS G31 Troubleshooting TS 12 2 MiCOM P746 TS BLANK PAGE...
Page 382: ...P746 EN SC G31 SCADA Communications MiCOM P746...
Page 424: ...P746 EN SC G31 SCADA Communications SC 13 42 MiCOM P746 SC BLANK PAGE...
Page 426: ...P746 EN SG F21 Symbols and Glossary MiCOM P746...
Page 438: ......
Page 440: ...P746 EN IN G31 Installation IN 15 2 MiCOM P746 IN BLANK PAGE...
Page 468: ......
Page 470: ...P746 EN HI G31 Remote HMI HI 16 2 MiCOM P746 HI BLANK PAGE...
Page 500: ...P746 EN HI G31 Remote HMI HI 16 32 MiCOM P746 HI BLANK PAGE...
Page 502: ......
Page 504: ...P746 EN CS A11G31 Cyber Security CS 17 2 MiCOM P746 CS BLANK PAGE...
Page 524: ...P746 EN VH G31 Firmware and Service Manual Version History MiCOM P746...
Page 529: ......