GE Multilin G650, Руководство пользователя

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GEK-113285A G650 Generator Protection & Control System 5-87
5 SETTINGS 5.5 CONTROL ELEMENTS
5
The Closing process using anticipative algorithm is described on the following figure:
Figure 5–18: ANTICIPATIVE ALGORITHM
Where:
V
ref
Referenced phasor (the one with lower frequency)
V
s
Actual voltage phasor (the one with lower frequency)
V’
s
Calculated voltage phasor, depending on the set breaker closing time (anticipative algorithm)
ϕ
360º *TCB *
Δ
f = Calculated angle for phasor V’
s
TCB
Breaker Closing time defined by setting
Δ
f
Frequency slip (mHz) between phasors
ϕ
1
Angle difference set as maximum angle difference (
Δϕ
set ,
Max Angle Difference)
ϕ
2
= Angle difference between V
ref
and V
s.
The algorithm starts operating when
ϕ
2
equals two times the angle
set as maximum angle difference.
Closing permission is given when
V’
s
is over
V
ref
, which means that line and busbar voltages are in phase.
If the frequency slip is high, it is possible that as soon as the window defined by two times the maximum angle difference
(
ϕ
2
) is entered, the relay will produce a closing permission output, if it is guaranteed that the projected phasor will be within
the limit marked by the setting, as shown in the following figure.
Figure 5–19: HIGH SLIP CLOSING PERMISSION SIGNAL
V
Ref
V
M
1
M
2
V’
s
M
V
Ref
V
M
1
M
2
V’
s
M
M
1