Hitachi Relion 670 Series Applications Manual page 213

1MRK506375-UEN Rev. N
SelPhaseLine
Configuration parameters for selecting the measuring phase of the voltage for line, which can be a
single-phase (phase-neutral) or a positive sequence voltage.
PhaseShift
To compensate the phase shift between the measured bus voltage and line voltage when:
• different phase-neutral voltages are selected (for example UL1 for bus and UL2 for line);
• one available voltage is positive sequence and the other one is phase-neutral (for example Pos.
Seq. for bus and UL2 for line).
The set value is added to the measured line phase angle. The bus voltage is reference voltage.
Synchronizing settings
OperationSynch
The setting Off disables the Synchronizing function. With the setting On, the function is in the service
mode and the output signal depends on the input conditions.
UHighBusSynch and UHighLineSynch
The voltage level settings shall be chosen in relation to the bus/line network voltage. The threshold
voltages UHighBusSynch and UHighLineSynch have to be set lower than the value where the
network is expected to be synchronized. A typical value is 80% of the rated voltage.
UDiffSynch
Setting of the voltage difference between the line voltage and the bus voltage. The difference is set
depending on the network configuration and expected voltages in the two networks running
asynchronously. A normal setting is 0.10-0.15 p.u.
FreqDiffMin
The setting FreqDiffMin is the minimum frequency difference where the systems are defined to be
asynchronous. For frequency differences lower than this value, the systems are considered to be in
parallel. A typical value for FreqDiffMin is 10 mHz. Generally, the value should be low if both
synchronizing and synchrocheck functions are provided, and it is better to let the synchronizing
function close, as it will close at exactly the right instance if the networks run with a frequency
difference.
FreqDiffMax
The setting FreqDiffMax is the maximum slip frequency at which synchronizing is accepted. 1/
FreqDiffMax shows the time for the vector to move 360 degrees, one turn on the synchronoscope,
and is called Beat time. A typical value for FreqDiffMax is 200-250 mHz, which gives beat times on
4-5 seconds. Higher values should be avoided as the two networks normally are regulated to nominal
frequency independent of each other, so the frequency difference shall be small.
FreqRateChange
The maximum allowed rate of change for the frequency.
CloseAngleMax
Railway application RER670
Application manual
To avoid overlapping of the synchronizing function and the synchrocheck function the
setting FreqDiffMin must be set to a higher value than used setting FreqDiffM, respective
FreqDiffA used for synchrocheck.
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Section 12
Control
207