Alstom MiCOM P54 Series - 5.6.6.15 System checks for circuit breaker closing (P544;P546)

P54x/EN OP/La4 Operation
(OP) 5-198 MiCOM P543, P544, P545 & P546
OP
5.6.6.15 System checks for circuit breaker closing (P544/P546)
The system checks for circuit breaker closing logic is shown in AR Figure 45, Figure 46,
Figure 47, Figure 48, Figure 51 and Figure 52 (logic diagram supplement).
For thre
e phase auto-reclosing and control closing of the circuit breakers, system voltage
checks are separately selectable for :-
 CB1 reclosing as leader;
 CB1 reclosing as follower;
 CB1 control close;
 CB2 reclosing as leader;
 CB2 reclosing as follower;
 CB2 control close.
In the AUTORECLOSE settings, if the Num CBs is set to CB1 Only or CB2 Only, then the
operation of the circuit breaker will be the same as described for the corresponding leader
circuit breaker (for example CB1 operation will be the same as described by CB1L in the
diagrams and descriptions.
The system check options for each circuit breaker are enabled or disabled in the CBx SC all
setting (x = 1L, 2L, 1F, 2F) in the AUTORECLOSE column of the menu. If set to Disabled,
then no system checks are required on any shot, and the relevant settings are invisible.
Otherwise, the system check options that can be enabled for each breaker (as leader or
follower) are :-
System check option Setting
System checks not required for first shot of
auto-reclose
CBx SC Shot1
Fast synchronism check (note 2)
CBx SC ClsNoDly
Check synchronism stage 1 (note 1)
CBx SC CS1
Check synchronism stage 2 (note 1)
CBx SC CS2
Dead line / Live Bus
CBx SC DLLB
Live Line / Dead bus
CBx SC LLDB
Dead line / Dead bus
CBx SC DLDB
Note 1: Two separate (independent) system synchronism check stages are
available for each circuit breaker. Each stage has different slip
frequency and phase angle settings as described in section 5.7.
Not
e 2: A fast synchronism check auto-reclose option is available for the
three phase auto-reclose as leader circuit breaker, by menu setting
CBx SC ClsNoDly. When the setting is enabled, then if the line and
bus come into synchronism (i.e. line energised from remote end) at
any time after the three phase dead time has started, a AutoClose
CB signal is issued immediately without waiting for the dead time to
elapse. This option is sometimes required for the second line end to
reclose on a line with delayed auto-reclosing (typical cycle: first line
end reclose after dead time with live bus & dead line, then second line
end reclose immediately with live bus & live line in synchronism).