ABB RELION REX640 Technical Manual page 974

Protection functions
Compensation of over-reaching with
Figure 548: Operation principle of top reactance line tilting
The tilt angle must be carefully set. If the tilt angle has been set to a value
where polygon boundaries do not form a close loop for an element, an internal
mechanism modifies the tilt angle for that element so that the polygon boundary
is always closed. If the set tilt angle is suitable for another element, the tilt angle
of that element is not internally modified. Tilt angle conflicts are monitored by
TLT_ANG_CONFLICT value. This integer value is a ten-bit value indicating tilt angle
modifications per zone and fault type.
Table 921: TLT_ANG_CONFLICT description
TLT_ANG_CONFLICT bit field
(MSB) xx xx xx xx YZ (LSB)
(MSB) xx xx xx YZ zz (LSB)
(MSB) xx xx YZ xx xx (LSB)
(MSB) xx YZ xx xx xx (LSB)
(MSB) YZ xx xx xx xx (LSB)
For example, TLT_ANG_CONFLICT value "36" = "00 00 10 01 00" indicates that the
tilt angles of the zone 2 earth-fault impedance element and zone 3 short circuit or
974
under-reaching zone
Tilt angle zone x < 0 deg.
X
Zone Z1
Compensation of under-reaching with
over-reaching zone
Tilt angle zone x > 0 deg.
X
Zone Z2
R
Description
Y active = Zone 1 earth-fault impedance ele-
ment tilt angle modified
Z active = Zone 1 short circuit impedance ele-
ment tilt angle modified
Y active = Zone 2 earth-fault impedance ele-
ment tilt angle modified
Z active = Zone 2 short circuit impedance ele-
ment tilt angle modified
Y active = Zone 3 earth-fault impedance ele-
ment tilt angle modified
Z active = Zone 3 short circuit impedance ele-
ment tilt angle modified
Y active = Zone 4 earth-fault impedance ele-
ment tilt angle modified
Z active = Zone 4 short circuit impedance ele-
ment tilt angle modified
Y active = Zone 5 earth-fault impedance ele-
ment tilt angle modified
Z active = Zone 5 short circuit impedance ele-
ment tilt angle modified
1MRS759142 F
R
REX640
Technical Manual