• Startup element is sensitive enough to detect the
abnormal status of the protected system
• Startup element does not influence the operation speed of
main protection
• Startup element would detect the evolving faults, high
impedance faults and three phase fault on weak side
• It is possible to block the each sub function of startup
element
• Startup signal has a settable pulse time
4. Impedance protection
Distance protection zone, quadrilateral characteristic
ZMQPDIS, ZMQAPDIS
The line distance protection is an up to five (depending on
product variant) zone full scheme protection function with three
fault loops for phase-to-phase faults and three fault loops for
phase-to-earth faults 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.
Distance measuring zone, quadrilateral characteristic
(ZMQPDIS) together with Phase selection with load
encroachment (FDPSPDIS) has functionality for load
encroachment, which increases the possibility to detect high
resistive faults on heavily loaded lines, as shown in figure
.
en05000034.vsd
R
X
Forward
operation
Reverse
operation
IEC05000034 V1 EN
Figure 7.
Typical quadrilateral distance protection zone with Phase
selection with load encroachment function FDPSPDIS
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-phase 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 independently 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.
Distance measuring zone, quadrilateral characteristic for
series compensated lines ZMCPDIS, ZMCAPDIS
The line distance protection is an up to five (depending on
product variant) 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 resistive and reactive reach give flexibility
for use on overhead lines and cables of different types and
lengths.
Quadrilateral characteristic is available.
Distance measuring zone, quadrilateral characteristic for series
compensated lines (ZMCPDIS) function has functionality for
load encroachment which increases the possibility to detect
high resistive faults on heavily loaded lines.
en05000034.vsd
R
X
Forward
operation
Reverse
operation
IEC05000034 V1 EN
Figure 8.
Typical quadrilateral distance protection zone with load
encroachment function 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
phase auto-reclosing.
Built-in adaptive load compensation algorithm for the
quadrilateral function prevents overreaching of zone1 at load
1MRK 506 372-BEN -
Line distance protection REL670 2.2
Product version: 2.2
26
ABB
