ABB Relion RES670, Technical Manual

Page: 157 / 934

7.1.6.4 Basic detection logic
M13877-24 v7
The operation of the Power swing detection ZMRPSB (68) is only released if the
magnitude of the current is above the setting of the min operating current,
IMinPUPG .
ZMRPSB (68) function can operate in two operating modes:
• The 1 out of 3 operating mode is based on detection of power swing in any of the
three phases. Figure 38 presents a composition of an internal detection signal
DET-A in this particular phase.
• The 2 out of 3 operating mode is based on detection of power swing in at least two
out of three phases. Figure 39 presents a composition of the detection signals
DET1of3 and DET2of3.
Signals ZOUT_n (outer boundary) and ZIN_n (inner boundary) in figure 38 are related
to the operation of the impedance measuring elements in each phase separately ( n
represents the corresponding A, B and C). They are internal signals, calculated by
ZMRPSB (68) function.
The tP1 timer in figure 38 serve as detection of initial power swings, which are usually
not as fast as the later swings are. The tP2 timer become activated for the detection of
the consecutive swings, if the measured impedance exit the operate area and returns
within the time delay, set on the
tW waiting timer. The upper part of figure 38 (internal
input signal ZOUT_A, ZIN_A, AND-gates and tP-timers) are duplicated for phase B
and C. All
tP1 and tP2 timers in the figure have the same settings.
ANSI05000113-2-en.vsd
AND
ZINA
AND
DET-A
OR
AND
AND
ZOUTA
-loop
ZOUTB
ZOUTC
OR
detected
OR
-loop
0-tP1
0
0-tP2
0
0
0-tW
ANSI05000113 V2 EN-US
Figure 38: Detection of power swing in phase A
1MRK 511 408-UUS A
Section 7
Impedance protection
Phasor measurement unit RES670 2.2 ANSI 151
Technical manual