If the fault is permanent, the line protection will trip again when reclosing is
attempted in order to clear the fault.
It is common to use one automatic reclosing function per line circuit breaker (CB).
When one CB per line end is used, then there is one auto- recloser per line end. If
auto reclosers are included in duplicated line protection, which means two auto
reclosers per CB, one should take measures to avoid uncoordinated reclosing
commands.
The auto recloser can be selected to perform multiple shots. The auto reclosing
dead time can be set to give either High-Speed Automatic Reclosing (HSAR) or
Delayed Automatic Reclosing (DAR). HSAR usually means a dead time of less
than 1 second.
The mode of automatic reclosing varies. Single-shot and multi-shot are in use. The
first shot can have a short delay, HSAR, or a longer delay, DAR. The second and
following reclosing shots have a rather long delay. When multiple shots are used
the dead time must harmonize with the breaker duty-cycle capacity.
Automatic reclosing is usually started by the line protection and in particular by
instantaneous tripping of such protection. The auto recloser can be inhibited
(blocked) when certain protection functions detecting permanent faults (e.g.
thermal overload protection). Back-up protection zones indicating faults outside the
own line are typically connected to inhibit the auto recloser.
Automatic reclosing should not be attempted when closing a CB and energizing a
line onto a fault (SOTF), except when multiple-shots are used where shots 2 etc.
will be started at SOTF. Auto reclosing is often combined with a release condition
from synchrocheck and dead line or dead busbar check.
Protection systems are usually sub-divided and provided with two redundant
protection IEDs. In such systems it is common to provide auto reclosing in only
one of the sub-systems as the requirement is for fault clearance and a failure to
reclose because of the auto recloser being out of service is not considered a major
disturbance. If two auto reclosers are provided on the same breaker, the application
must be carefully checked and normally one must be the master and be connected
to inhibit the other auto recloser if it has started. This inhibit can, for example, be
done from an auto recloser by using operation in progress signal.
A permanent fault will cause the line protection to trip again when it recloses in an
attempt to energize the line.
The auto reclosing function allows a number of parameters to be adjusted.
Examples:
•
number of auto reclosing shots
•
auto reclosing dead times for each shot
1MRK 506 375-UEN A
Section 12
Control
Railway application RER670 2.2 IEC
225
Application manual
Содержание RELION RER670
Страница 1: ...RELION 670 SERIES Railway application RER670 Version 2 2 IEC Application manual ...
Страница 2: ......
Страница 22: ...16 ...
Страница 48: ...42 ...
Страница 70: ...64 ...
Страница 80: ...74 ...
Страница 100: ...94 ...
Страница 210: ...204 ...
Страница 364: ...358 ...
Страница 384: ...378 ...
Страница 468: ...462 ...
Страница 494: ...488 ...
Страница 504: ...498 ...
Страница 505: ...499 ...