ABB RELION 670 Series Applications Manual page 362

Section 7
Impedance protection
Connect the CACC functional input to start output signal of the local overreaching power
swing distance protection zone, which serves as a local criteria at receiving of carrier signal
during the power swing cycle.
The CR signal should be configured to the functional input which provides the logic with
information on received carrier signal sent by the remote end power swing distance protection
zone.
The CS functional output signal should be configured to either output relay or to
corresponding input of the "Binary signal transfer to remote end" function.
The BLKZMPS output signal should be configured to BLOCK input of the power swing distance
protection zones.
The TRIP signal should be connected correspondingly towards the tripping functionality of the
complete distance protection within the IED.
Setting calculations
Time delay of power swing carrier send distance protection zones
Time delay for the underreaching or overreaching carrier send power swing zone should be set
shorter (with sufficient margin) than the time delay of normal distance protection zone 2 to
obtain selective time grading also in cases of faults during power swings. The necessary time
difference depends mostly on the speed of the communication channel used, speed of the
circuit breaker used, etc. Time difference between 100 ms and 150 ms is generally sufficient.
Reactive reach setting of power swing distance protection zones
Set the reactive reach for the power swing zones according to the system selectivity planning.
The reach of the underreaching zone should not exceed 85% of the protected line length. The
reach of the overreaching zone should be at least 120% of the protected line length.
Resistive reach setting of carrier send power swing distance protection zone
Determine the minimum possible speed of impedance Δ
power swings. When better information is not available from system studies, the following
equation may be used:
= ×
v 2
z
EQUATION1537 V1 EN-US
Where:
v
z
Z
Lmin
f
smin
Calculate the maximum permissible resistive reach for each power swing zone separately
according to the following equations.
RFPP
EQUATION1538 V1 EN-US
356
×
Z f
L min s min
is a minimum expected speed of swing impedance in Ω /
is a minimum expected primary load impedance in Ω
is a minimum expected oscillation (swing) frequency in
= × ×
v tnPP 0.8
n z
Z / Δ t in primary Ω / s of the expected
s
Hz
1MRK 504 152-UEN B
SEMOD131360-29 v1
SEMOD131360-32 v2
SEMOD131360-37 v2
SEMOD131360-40 v2
(Equation 401)
(Equation 402)
Application manual