ABB Relion 670 Series Applications Manual page 447

1MRK 511 358-UUS A
important for those involved in operation and maintenance. Reliable information on the fault
location greatly decreases the downtime of the protected lines and increases the total availability
of a power system.
The fault locator is started with the input CALCDIST to which trip signals indicating in-line faults
are connected, typically distance protection zone 1 and accelerating zone or the line differential
protection. The disturbance report must also be started for the same faults since the function
uses pre- and post-fault information from the trip value recorder function (TVR).
Beside this information the function must be informed about faulted phases for correct loop
selection (phase selective outputs from differential protection, distance protection, directional OC
protection, and so on). The following loops are used for different types of faults:
• for 3 phase faults: loop A-B.
• for 2 phase faults: the loop between the faulted phases.
• for 2 phase-to-ground faults: the loop between the faulted phases.
• for phase-to-ground faults: the phase-to-ground loop.
LMBRFLO function indicates the distance to fault as a percentage of the line length, in kilometers
or miles as selected on the local HMI.
either, in
with a high accuracy, is stored together with the recorded disturbances. This information can be
read on the local HMI, uploaded to PCM600 and is available on the station bus according to IEC
61850–8–1.
The distance to fault can be recalculated on the local HMI by using the measuring algorithm for
different fault loops or for changed system parameters.
16.8.3 Setting guidelines
The parameters for the Fault locator function are set via the local HMI or PCM600.
The Fault locator algorithm uses phase voltages, phase currents and residual current in observed
bay (protected line) and residual current from a parallel bay (line, which is mutual coupled to
protected line).
The Fault locator has close connection to the Disturbance report function. All external analog
inputs (channel 1-30), connected to the Disturbance report function, are available to the Fault
locator and the function uses information calculated by the Trip value recorder. After allocation of
analog inputs to the Disturbance report function, the user has to point out which analog inputs to
be used by the Fault locator. According to the default settings the first four analog inputs are
currents and next three are voltages in the observed bay (no parallel line expected since chosen
input is set to zero). Use the Parameter Setting tool within PCM600 for changing analog
configuration.
The measured phase voltages can be fine tuned with the parameters
to further increase the accuracy of the fault locator.
The list of parameters explains the meaning of the abbreviations. Figure
system parameters graphically. Note, that all impedance values relate to their primary values and
to the total length of the protected line.
Application manual
kilometer or miles for the distance to fault. The distance to the fault, which is calculated
LineLengthUnit setting is used to select the unit of length
Section 16
Monitoring
VAGain , VBGain and VCGain
206 also presents these
IP14835-1 v1
M13769-3 v6
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