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This reclosing mode is simply expressed as "SPAR & TPAR" in the following descriptions.
Multi-phase autoreclose:
This autoreclose mode can be applied to double-circuit lines. In this mode, only the faulted
phases are tripped and reclosed when the terminals of double-circuit lines are
interconnected during the dead time through at least two or three different phases.
This mode realizes high-speed reclosing for multi-phase faults without synchronism and
voltage check and minimizes the possibility of outages in the case of double faults on
double-circuit lines.
If the interlinking condition is not satisfied, all the phases are tripped and reclosing is not
started.
This reclosing mode is simply expressed as "MPAR2" for two-phase interconnection and
"MPAR3" for three-phase interconnection in the following descriptions.
For the detailed performance of the multi-phase autoreclose, see Appendix M.
In B-mode and GPS-mode, the multi-phase autoreclose can be applied if the RYIDSV
function is not applied.
Single-shot autoreclose can be applied to one-breaker reclosing and two-breaker reclosing in the
one-and-a-half breaker busbar system.
Multi-shot autoreclose
In the multi-shot autoreclose, any of two- to four-shot reclosing can be selected. In any case, the
first shot is selected from four types of autoreclose mode as described in the above single-shot
autoreclose. All successive shots (up to three times), which are applied if the first shot fails, are
three-phase tripping and reclosing.
Multi-shot autoreclose cannot be applied to two-breaker reclosing in the one-and-a-half breaker
busbar system.
The autoreclose can also be activated from an external line protection. At this time, all
autoreclose modes described above are effective.
If a fault occurs under the following conditions, three-phase final tripping is performed and
autoreclose is blocked:
• Reclosing block signal is received from an external unit locally or remotely.
• Throughout the reclaim time.
For evolving faults that occur during the dead time between single-phase tripping and reclosing,
"SPAR & TPAR" functions are as follows.
For evolving faults that occur within the period of time set from the first fault, the reclosing
mode enters the three-phase autoreclose mode. At this time, the total dead time becomes the dead
time for three-phase autoreclose added to the dead time for single-phase autoreclose which has
expired up to the point at which the evolving fault occurs.
For evolving faults that occurred after the set time, three-phase final tripping is performed, and
reclosing is not performed.
If an evolving fault occurs when "SPAR" is selected, three-phase final tripping is performed, and
reclosing is not performed.
If an evolving fault occurs when "MPAR2" or "MPAR3" is selected, the dead time is recounted
provided the network conditions defined for linked circuits are satisfied.
114
6 F 2 S 0 8 5 0
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