ZMax
Estimated maximum impedance value. An impedance that is higher than
ZMax
has
the quality attribute as “Out of Range”.
ZMin
Estimated minimum impedance value. An impedance that is lower than
ZMin
has
the quality attribute as “Out of Range”.
7.2
Power swing detection ZMRPSB
IP14499-1 v3
7.2.1
Identification
M14853-1 v3
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Power swing detection
ZMRPSB
Zpsb
SYMBOL-EE V1 EN-US
68
7.2.2
Application
IP14969-1 v1
7.2.2.1
General
M13874-3 v3
Various changes in power system may cause oscillations of rotating units. The most
typical reasons for these oscillations are big changes in load or changes in power
system configuration caused by different faults and their clearance. As the rotating
masses strive to find a stable operate condition, they oscillate with damped
oscillations until they reach the final stability.
The extent of the oscillations depends on the extent of the disturbances and on the
natural stability of the system.
The oscillation rate depends also on the inertia of the system and on the total
system impedance between different generating units. These oscillations cause
changes in phase and amplitude of the voltage difference between the oscillating
generating units in the power system, which reflects further on in oscillating power
flow between two parts of the system - the power swings from one part to another -
and vice versa.
Distance IEDs located in interconnected networks see these power swings as the
swinging of the measured impedance in relay points. The measured impedance
varies with time along a locus in an impedance plane, see figure
. This locus can
enter the operating characteristic of a distance protection and cause, if no
preventive measures have been considered, its unwanted operation.
Section 7
1MRK 505 393-UEN B
Impedance protection
134
Line differential protection RED650 2.2 IEC
Application manual
Summary of Contents for RED650
Page 1: ...RELION 650 SERIES Line differential protection RED650 Version 2 2 Application manual ...
Page 2: ......
Page 22: ...16 ...
Page 32: ...26 ...
Page 82: ...76 ...
Page 112: ...106 ...
Page 152: ...146 ...
Page 208: ...202 ...
Page 214: ...208 ...
Page 282: ...276 ...
Page 356: ...350 ...
Page 404: ...398 ...
Page 408: ...402 ...
Page 442: ...436 ...
Page 452: ...446 ...
Page 453: ...447 ...