Function Block; Functionality - ABB RELION 630 Series Technical Manual

1MRS757256 F
7.4.2
7.4.3
PML630/Compact Load-Shedding Solution
Technical Manual

Function block

PSCSWI
I_A
I_B
I_C
POWER
CB_POSITION
CB_SERVICE
CB_LOCK_OUT
CB_IED_QVAL
IED_TST_MODE
MAX_POWER
GOVERNOR_MOD
AP_GOV_QVAL
ISLAND_PARAL
ENA_MULT
EXT_OC_SLST
INHIBIT_TRG
SLS_DISABLE
RESET_OC
RESET_DEMAND
GUID-A7713E52-6998-4D40-9741-34FE541B3CC7 V1 EN
Figure 130: Function block

Functionality

The input interface function PSCSWI processes the circuit breaker status and power
values of the power source. PSCSWI identifies the load bus bar number to which the
power source is connected and provides the available power, active power and the
governor mode of the power source for the power balance calculation.
PSCSWI calculates the compensated circuit breaker position depending on the power
source IED quality status, circuit breaker position, circuit breaker service position and
protection lockout status.
PSCSWI generates the fast load-shedding trigger due to circuit breaker position
change or protection lockout operating and slow load-shedding trigger due to the
phase overcurrent detection or maximum demand violation.
PSCSWI also generates the load-shedding blocking signal due to the bad data quality
or power source IED in the test mode or power source circuit breaker position in
intermediate or invalid, that blocks the load-shedding.
When external inhibition input is active or blocking signal is active, the fast load-
shedding trigger and slow load-shedding trigger are inhibited.
Selecting the appropriate setting changes the power configuration, sign convention
and unit of the active power. PSCSWI also has the provision to select the available
power either as communication value or setting. Similarly, the governor mode for the
generator can be selected from the communication value or setting.
Power management functions
SOURCE
CB_COMPS_POS
FLS_TRIGGER
SLOWLS_OPR
OC_STR
OC_OPR
MAX_DMD_ALM
ISLND_PARALL
FLS_BLOCK
BLK_BYPASS
B_SET_CHANGE
INVAL_CRV
Section 7
215