Functions
6-59
7SA6 Manual
C53000-G1176-C156-2
Figure 6-32
Directional characteristic with quadrature or memorized voltages
Pick-up and
Assignment to the
Polygons
Using the fault detection modes
I
, U/
I
or U/
I
/
ϕ
according to Subsection 6.2.2 the im-
pedances, that were calculated from the valid loops, are assigned, after the pick-up,
to the zone characteristics set for the distance protection. To avoid unstable signals at
the boundaries of a polygon, the characteristics have a hysteresis of approximately
5 % i.e. as soon as it has been determined that the fault impedance lies within a pol-
ygon, the boundaries are increased by 5 % in all directions. The loop information is
also converted to faulted phase indication
Using the impedance pick-up the loop impedances calculated according to Subsection
6.2.3 are also assigned to the zone characteristics set for the distance protection, but
without a query of an explicite fault detection scheme. The pick-up range of the Dis-
tance Protection is determined from the thresholds of the largest-set polygon taking
into consideration the respective direction. Here the loop information is also converted
into faulted phase indication.
“Pick-up” signals are also generated for each zone and converted into phase informa-
tion, e.g.
Dis.Pickup L1 Z1
for zone Z1 and phase L1. This means that each phase
and each zone is provided with separate pick-up information. The information is then
processed in the zone logic (see Subsection 6.2.5) and by additional functions (e.g.
signal transmission logic, Subsection 6.6.1).
The loop information is also converted to phase indications. Further conditions for the
“pick-up” of a zone are that the direction must be in accordance with the configured
direction for the zone and that the zone is not blocked by the power swing blocking
(see Subsection 6.3.1). Furthermore the Distance Protection system must not be
switched off totally or blocked. Figure 6-33 shows the conditions mentioned.
F
2
F
1
E
1
E
2
Z
S1
Z
S2
Z
L
7SA6
“forward”
“reverse”
R
jX
I
2
I
1
F
1
Z
L
+ Z
S2
“forward”
“reverse”
R
jX
F
2
Z
S1
Z
L
+ Z
S2
6-32a
6-32c
6-32b
Z
S1
Summary of Contents for siprotec 7SA6
Page 2: ...Siemens Aktiengesellschaft Book No C53000 G1176 C156 2 ...
Page 18: ...xviii 7SA6 Manual C53000 G1176 C156 2 ...
Page 32: ...Introduction 1 14 7SA6 Manual C53000 G1176 C156 2 ...
Page 82: ...Hardware and Connections 2 50 7SA6 Manual C53000 G1176 C156 2 ...
Page 119: ...SIPROTEC 4 Devices 4 25 7SA6 Manual C53000 G1176 C156 2 Figure 4 20 CFC Logic example ...
Page 190: ...Configuration 5 62 7SA6 Manual C53000 G1176 C156 2 ...
Page 652: ...Installation and Commissioning 8 78 7SA6 Manual C53000 G1176 C156 2 ...
Page 724: ...Technical Data 10 56 7SA6 Manual C53000 G1176 C156 ...
Page 800: ...Appendix A 76 7SA6 Manual C53000 G1176 C156 2 ...
Page 866: ...Appendix B 66 7SA6 Manual C53000 G1176 C156 2 ...