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Section 12
Control
12.2.1
Identification
Function Description
Autorecloser for 1 phase, 2 phase and/or 3
phase
12.2.2
Application
In certain countries it is standard practice to provide delayed restoration after busbar
protection operation for internal fault, reason being that many busbar faults are of the
transient natures that is, animals, birds, storm, flying objects, etc. In such applications,
typically one pre-selected feeder is automatically closed with certain time delay in order to try
to re-energize the faulty bus. Typically, the longest overhead line is selected in order to limit
the fault current in case of permanent busbar fault. If the first feeder is successfully closed, all
other feeder which have been connected to the same busbar, are automatically put back into
service.
Sensitive differential protection level available in REB670 can be used during such operation, if
increased sensitivity from busbar protection is required. Such busbar restoration logic can be
implemented by using optionally available auto reclosers and built-in logical gates. Two auto
reclosers are available.
Automatic reclosing is a well-established method for the restoration of service in a power
system after a transient line fault. The majority of line faults are flashovers, which are transient
by nature. When the power line is switched off by the operation of line protection and line
breakers, the arc de-ionizes and recovers its ability to withstand voltage at a somewhat
variable rate. Thus, a certain dead time with a de-energized line is necessary. Line service can
then be resumed by automatic reclosing of the line breakers. The dead time selected should be
long enough to ensure a high probability of arc de-ionization and successful reclosing.
For individual line breakers, auto reclosing equipment, the required circuit breaker dead time
is used to determine the "dead time" setting value. When simultaneous tripping and reclosing
at the two line ends occurs, line dead time is approximately equal to the auto recloser "dead
time". If the auto reclosing dead time and line "dead time" differ then, the line will be energized
until the breakers at both ends have opened.
264
IEC 61850
IEC 60617
identification
identification
SMBRREC
5(0 -->1)
IEC15000204 V1 EN-US
1MRK 505 370-UEN D
M14890-1 v7
ANSI/IEEE C37.2
device number
79
M12391-3 v8
Busbar protection REB670
Application manual
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