ABB REL670 2.2 IEC, Applications Manual

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U2> : Level of high negative sequence voltage detection given in % of UBase . This
setting should be based on fault calculations to find the negative sequence voltage
in case of a fault at the most remote point where the direct trip scheme shall be
active. The negative sequence voltages shall be calculated for different types of
faults (single phase to earth, phase to phase to earth and phase to phase short
circuits) at different switching states in the network.
tU2 : Time delay for trip in case of high negative sequence voltage detection. The
trip function can be used as stand alone short circuit protection with a long time
delay. The choice of time delay is depending on the application of the protection as
well as network topology.
16.8.8 Zero sequence overvoltage protection LCZSPTOV
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16.8.8.1 Identification
GUID-0D2A007F-167A-4534-A41B-22C107FEAC46 v1
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Zero sequence overvoltage protection LCZSPTOV - 59N
16.8.8.2 Application
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Zero sequence symmetrical components are present in all abnormal conditions
involving earth. They have a considerably high value during earth faults.
Zero sequence overvoltage protection (LCZSPTOV) is a definite time stage
comparator function. The Zero sequence input voltage from the SMAI block is
connected as input to the function through a group connection U3P in PCM600.
This voltage is compared against the preset value and a start signal will be set high
if the input zero sequence voltage is more than the preset value
3U0> . Trip signal
will be set high after a time delay setting of t3U0 . BLOCK input will block the
complete function. BLKTR will block the trip output . Zero sequence voltage will
be available as service value output as 3U0.
16.8.8.3 Setting guidelines
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GlobalBaseSel : Selects the global base value group used by the function to define
IBase , UBase and SBase as applicable.
The IED is fed from a normal voltage transformer group where the residual voltage
is created from the phase to earth voltages within the protection software or the
residual voltage is fed from a broken delta-connected VT-group. The setting of
analogue inputs always gives 3U0. Therefore set:
Section 16
1MRK 506 369-UEN B
Scheme communication
736 Line distance protection REL670 2.2 IEC
Application manual