Phase Preference Logic Pplphiz; Identification; Application - ABB RELION 670 Series Applications Manual

1MRK 504 152-UEN B
Operation : With the setting Operation OOSPPAM function can be set On/Off .
•
• OperationZ1 : Operation zone 1 On , Off . If OperationZ1 = Off , all pole-slips with centre of
the electromechanical oscillation within zone 1 are ignored. Default setting =
likely to be used is the option to extend zone 1 so that zone 1 even covers zone 2. This
feature is activated by the input to extend the zone 1 (EXTZ1).
OperationZ2 : Operation zone 2 On , Off . If OperationZ1 = Off , all pole-slips with centre of
•
the electromechanical oscillation within zone 2 are ignored. Default setting =
tBreaker : Circuit breaker opening time. Use the default value tBreaker = 0.000 s if
•
unknown. If the value is known, then a value higher than 0.000 is specified, for example
tBreaker = 0.040 s : the out-of-step function gives a trip command approximately 0.040
seconds before the currents reach their minimum value. This in order to decrease the
stress imposed to the circuit breaker.
GlobalBaseSel : This setting identifies the Global Base Values Group where UBase and
•
IBase are defined. In particular: UBase is the voltage at the point where the Out-of-step
protection is connected. If the protection is connected to the generator output terminals,
then
the resistances and reactances are measured and displayed referred to voltage
Observe that
UBase.IBase is the protected generator nominal (rated) current, if the Out-of-step
protection belongs to a generator protection scheme.
InvertCTCurr : If the currents fed to the Out-of-step protection are measured on the
•
protected generator neutral side (LV-side) then inversion is not necessary (
Off ), provided that the CT's star point earthing complies with ABB recommendations, as it
is shown in Table 33. If the currents fed to the Out-of-step protection are measured on the
protected generator terminals side, then invertion is necessary (
provided that the CT's star point earthing complies with ABB recommendations, as it is
shown in Table 33.
7.18

Phase preference logic PPLPHIZ

7.18.1

Identification

Function description
Phase preference logic
7.18.2

Application

Phase preference logic function PPLPHIZ is an auxiliary function to Distance protection zone,
quadrilateral characteristic ZMQPDIS and Phase selection with load encroachment,
quadrilateral characteristic function FDPSPDIS. The purpose is to create the logic in resonance
or high resistive earthed systems (normally sub-transmission) to achieve the correct phase
selective tripping during two simultaneous single-phase earth-faults in different phases on
different line sections.
Due to the resonance/high resistive earthing principle, the earth faults in the system gives
very low fault currents, typically below 25 A. At the same time, the occurring system voltages
on the healthy phases will increase to line voltage level as the neutral displacement is equal to
the phase voltage level at a fully developed earth fault. This increase of the healthy phase
voltage, together with slow tripping, gives a considerable increase of the risk of a second fault
in a healthy phase and the second fault can occur at any location. When it occurs on another
feeder, the fault is commonly called cross-country fault.
Application manual
UBase is the nominal (rated) phase to phase voltage of the protected generator. All
ReverseX , ForwardX , ReverseR , and ForwardR must be given referred to
IEC 61850 IEC 60617
identification identification
PPLPHIZ -
Section 7
Impedance protection
On . More
On .
Ubase .
InvertCTCurr =
InvertCTCurr = On ),
SEMOD151920-1 v2
SEMOD151937-2 v2
ANSI/IEEE C37.2
device number
-
SEMOD167856-4 v5
375