CYG PRS-7367 - Operation Principle

Protection Functions
PRS-7367 129
NO.
Signal
Description
1
ChkOK
Synchronizing OK or dead charge check OK output
2
DLDBOK
Dead line and dead bus condition is met
3
DLLBOK
Dead line and live bus condition is met
4
LLDBOK
Live line and dead bus condition is met
5
DdChkOK
Dead charge check is OK
6
VolDiffOK
To indicate that voltage difference condition for synchronism
check of AR is met, voltage difference between reference
voltage and synchronism voltage is smaller than
25SYN_Vol_Diff.
7
FrDiffOK
To indicate that frequency difference condition for
synchronism check of AR is met, frequency difference
between reference voltage and synchronism voltage is
smaller than 25SYN_Fr_Diff.
8
AngDiffOK
To indicate that phase angle difference condition for
synchronism check of AR is met, phase angle difference
between reference voltage and synchronism voltage is
smaller than 25SYN_Ang_Diff.
9
SynChkOK
Synchronism is OK
10
UsynVTSAlm
Synchronism circuit failure alarm signal
11
UsynPhsAlm
Synchronism phase error alarm signal
3.23.2 Operation Principle
The synchronism check function is mainly to measure the electrical quantities between both sides
of the circuit breaker and compares them with the corresponding settings. The output is only given
if all measured quantities are simultaneously within their set limits.
3.23.2.1 Synchronization Voltage Selection
3.23.2.2 Dead Charge Check Logic
The bus/line dead criterion is:
U<25SYN_Vol_Dd
Where: