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 ΔZ / Δt in primary Ω / s of the
expected power swings. When better information is not available from system studies, the
following equation may be used:
EQUATION1537 V1 EN (Equation 421)
Where:
v
z
is a minimum expected speed of swing impedance in Ω /
s
Z
Lmin
is a minimum expected primary load impedance in Ω
f
smin
is a minimum expected oscillation (swing) frequency in
Hz
Calculate the maximum permissible resistive reach for each power swing zone separately
according to the following equations.
1MRK 506 369-UUS - Section 8
Impedance protection
Line distance protection REL670 2.2 ANSI 449
Application manual
To Next Page
Loading...
