GE LPS-D, Инструкция по эксплуатации

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GE Power Management LPS-D Line Protection System 1-
15
1 PRODUCT DESCRIPTION 1.4 AUXILIARY PROTECTION FUNCTIONS
1
Timer TL403 is provided for those cases where simultaneous high-speed reclosing is employed at both ends of
the line, and where the I1 function must be set to pick up below the maximum load current that can occur at
that time. TL403 then allows time for the voltage to return to normal and take Line Pickup out of service before
it can trip on load current. If simultaneous high-speed reclosing is not used, timer TL403 can be permanently
bypassed.
b) SINGLE PHASE TRIPPING
Logic is also included in the LPS-D with single phase tripping models to provide high-speed tripping when a
single phase reclose onto a permanent fault occurs. When a phase of the circuit breaker is open, the associ-
ated timer (TL404, TL405, and TL406) picks up to provide one input to an AND gate (AND404, AND405, or
AND406). This AND gate allows the associated Zone 2 ground distance function to trip without time delay, and
without receiving a permissive channel signal from the remote terminal. The single phase line pickup logic will
be blocked 90 ms after the breaker pole has been closed by the dropout of the timer.
1.4.3 REMOTE-OPEN DETECTOR
The Remote-Open Detector (ROD) function issues a trip signal when the remote breaker opens during an
unbalanced internal fault. This function detects that the remote breaker has opened by recognizing charging
current on one or more phases following opening of the remote breaker. As shown in the functional logic dia-
gram below, the ROD output trips via OR2, AND1, OR2, AND2, OR3, and AND4. The Remote-Open Detector
will not operate when a balanced three-phase fault is present.
Figure 1–5: REMOTE-OPEN DETECTOR LOGIC
The Remote-Open detector can speed up tripping at the end of the line that otherwise would be the slowest to
respond in a sequential-tripping condition. In a Step Distance scheme, ROD tripping is beneficial for any unbal-
anced internal fault not detected by Zone 1. In a Blocking scheme, ROD tripping is beneficial where system
conditions are such that the fault current redistribution following breaker opening at one end is normally
required before the other end(s) operates. The ROD function should not be considered as a replacement or
substitute for a pilot scheme.
Figure 1–5: REMOTE-OPEN DETECTOR LOGIC above is a functional logic diagram of the ROD function. The
sequence of events that results in an ROD output is as follows:
1. No charging current is detected prior to the fault – logic 0 output from AND2.
2. A fault is detected – logic 1 output from OR3.
3. The remote breaker opens – logic 1 output from AND3.
A
0
I A L E A D S
V A B Y 9 0 °
I B L E A D S
V B B Y 9 0 °
I C L E A D S
V C B Y 9 0 °
F A U L T
D E T E C T O R
A N Y Z O N E 2
P H A S E - D I S T A N C E
F U N C T I O N
A N Y Z O N E 2
G R O U N D - D I S T A N C E
F U N C T I O N
1
1
2
2
4
3
3
A = 10 - 100
T L 2 0
T R I P
RemoteOpen.vsd