GE RPV311, Technical Manual

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Chapter 9
– TW Fault Locator
RPV311
144 RPV311-TM-EN-7
The RPV from one terminal does not need to communicate with the other terminal’s
RPV in order to create the TW COMTRADE file.
A communication link is only needed between the control centers and the RPVs (or
local data concentrators) the user wants to implement remote access to the
equipment.
The communication setup that the user would deploy to download the TW record
and perform the fault location is exactly the same as the one used to download the
fault records.
The fault distance is calculated based on the time that each wavefront arrived at the
line terminal. According to the following equation.
𝑑 =
𝑙 + 𝐾𝑐(𝑡
𝑎
− 𝑡
𝑏
)
2
Where:
d: fault distance from terminal A;
l: length of the line;
k: constant of the line attenuation of the speed of the wave;
c: speed of light
t
a:
time which the traveling wave gets to terminal A
t
b :
time which the traveling wave gets to terminal B
The means to get the COMTRADE files from the RPV311 to the computer where the
fault location will be performed are described in Chapter 5: Operation, COMTRADE
files download.
The TW record is a COMTRADE file with 100ms prior to the trigger plus 1 cycle after
the trigger, that means approximately 117 ms @ 60 Hz and 120 ms @ 50 Hz. The
RPV311 takes 2 minutes to create a record and during that time the device stays in a
“BUSY” status and will not record a new TW record until the BUSY status is finished.
2 TW Fault Location Information
2.1 Maximum Number of Lines Monitored by the TW Fault
Locator
If the voltage is sourced from a bus VT you only need one RA333 to capture TWs from
all the lines connected to that bus, however simultaneous or consecutive faults (less
than 2 minutes apart) on lines connected to that bus will not be captured.. Moreover,
it is possible to connect up to 4 modules RA333 to one processing unit RPV311.