Functions When Using Signals From Iec 61850-9-2Le Communication - ABB RET670 Applications Manual

1MRK504116-UUS C
4.3.2.2
4.3.2.3
Application manual
Consequence on accuracy for power measurement functions when
using signals from IEC 61850-9-2LE communication
The Power measurement functions (CVMMXN, CMMXU, VMMXU and VNMMXU)
contains correction factors to account for the non-linearity in the input circuits, mainly
in the input transformers, when using direct analogue connection to the IED.
The IED will use the same correction factors also when feeding the IED with analog
signals over IEC 61850-9-2LE. Since the signals via IEC 61850-9-2LE are not subject
to the same non-linearity errors this will cause an inaccuracy in the measured values.
For voltage signals the correction factors are less than 0.05% of the measured value
and no angle compensation why the impact on reported value can be ignored.
For current signals the correction factors will cause a not insignificant impact on the
reported values at low currents. The correction factors are +2.4% and -3.6 degrees at
signal levels below 5% of set base current, +0.6% and -1.12 degrees at signal level
30% of set base current and 0% and -0.44 degrees at signal levels above 100% of set
base current. Between the calibration points 5%, 30% and 100% of set base current,
linear interpolation is used. Since the output from the Power measurement function is
used as an input for the Energy measuring function (ETPMMTR) the above described
impact will also be valid for the output values for ETPMMTR.
Loss of communication
If IEC 61850-9-2LE communication is lost, protection functions in table 240are blocked:
Table 240: Blocked protection functions if IEC 61850-9-2LE communication is interrupted.
Function description IEC 61850 identification
Broken conductor check BRCPTOC
Capacitor bank CBPGAPC
protection
Breaker failure CCRBRF
protection
Pole discordance CCRPLD
protection
Breaker failure CCSRBRF
protection, single phase
version
Current circuit CCSRDIF
supervison
Compensated over- and COUVGAPC
undervoltage protection
General currrent and CVGAPC
voltage protection
Table continues on next page
Station communication
Function description IEC 61850 identification
Phase preference logic PPLPHIZ
PoleSlip/Out-of-step PSPPPAM
protection
Restricted earth fault REFPDIF
protection, low
impedance
Two step residual ROV2PTOV
overvoltage protection
Rate-of-change SAPFRC
frequency protection
Overfrequency SAPTOF
protection
Underfrequency SAPTUF
protection
Sudden change in SCCVPTOC
current variation
Section 4
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