ABB Relion 670 Series Product Manual page 26

Line differential protection RED670 2.0
Product version: 2.0
Faulty phase identification with load encroachment FMPSPDIS
The ability to accurately and reliably classify different types of
fault so that single phase tripping and autoreclosing can be
used plays an important roll in today's power systems.
The phase selection function is design to accurately select the
proper fault loop(s) in the distance function dependent on the
fault type.
The heavy load transfer that is common in many transmission
networks may in some cases interfere with the distance
protection zone reach and cause unwanted operation.
Therefore the function has a built in algorithm for load
encroachment, which gives the possibility to enlarge the
resistive setting of the measuring zones without interfering with
the load.
The output signals from the phase selection function produce
important information about faulty phase(s), which can be used
for fault analysis as well.
Distance protection zone, quadrilateral characteristic,
separate settings ZMRPDIS, ZMRAPDIS
The line distance protection is up to five zone full scheme
protection with three fault loops for phase-to-phase faults and
three fault loops for phase-to-earth fault for each of the
independent zones. Individual settings for each zone in resistive
and reactive reach gives flexibility for use as back-up protection
for transformer connected to overhead lines and cables of
different types and lengths.
Mho alternative quadrilateral characteristic is available.
ZMRPDIS together with Phase selection, quadrilateral
characteristic with settable angle FRPSPDIS has functionality
for load encroachment, which increases the possibility to
detect high resistive faults on heavily loaded lines, as shown in
figure 11.
26
X
Reverse
operation
IEC05000034 V1 EN
Figure 15. Typical quadrilateral distance protection zone with Phase
selection, quadrilateral characteristic with settable angle
function FRPSPDIS activated
The independent measurement of impedance for each fault
loop together with a sensitive and reliable built-in phase
selection makes the function suitable in applications with single
pole tripping and autoreclosing.
Built-in adaptive load compensation algorithm prevents
overreaching of zone 1 at load exporting end at phase-to-earth
faults on heavily loaded power lines.
The distance protection zones can operate, independent of
each other, in directional (forward or reverse) or non-directional
mode. This makes them suitable, together with different
communication schemes, for the protection of power lines and
cables in complex network configurations, such as parallel
lines, multi-terminal lines and so on.
Phase selection, quadrilateral characteristic with settable
angle FRPSPDIS
The operation of transmission networks today is in many cases
close to the stability limit. Due to environmental considerations,
the rate of expansion and reinforcement of the power system is
reduced for example, difficulties to get permission to build new
power lines. The ability to accurately and reliably classify the
different types of fault, so that single pole tripping and
autoreclosing can be used plays an important role in this
matter. The phase selection function is designed to accurately
select the proper fault loop in the distance function dependent
on the fault type.
The heavy load transfer that is common in many transmission
networks may make fault resistance coverage difficult to
achieve. Therefore, the function has a built in algorithm for load
encroachment, which gives the possibility to enlarge the
resistive setting of both the phase selection and the measuring
zones without interfering with the load.
1MRK505310-BEN C
Forward
operation
R
en05000034.vsd
ABB