Fault Locator Lmbrflo; Identification; Application; Setting Guidelines - ABB Relion REC670 Applications Manual

1MRK 511 358-UEN A
16.8

Fault locator LMBRFLO

16.8.1

Identification

Function description
Fault locator
16.8.2

Application

The main objective of line protection and monitoring IEDs is fast, selective and reliable
operation for faults on a protected line section. Besides this, information on distance to fault
is very 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 L1 - L2.
• for 2 phase faults: the loop between the faulted phases.
• for 2 phase-to-earth faults: the loop between the faulted phases.
• for phase-to-earth faults: the phase-to-earth 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.
unit of length either, in
which is calculated 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
Application manual
IEC 61850
identification
LMBRFLO
kilometer or miles for the distance to fault. The distance to the fault,
IEC 60617 ANSI/IEEE C37.2
identification device number
- -
LineLengthUnit setting is used to select the
Section 16
Monitoring
IP14592-1 v2
M14892-1 v3
M13752-3 v6
IP14835-1 v1
M13769-3 v6
397