Faulty Phase Identification With Load Encroachment For Mho Fmpspdis - ABB REL650 Applications Manual

1MRK 506 334-UUS A
3.1.5
3.1.6
Application manual
Faulty phase identification with load encroachment for mho
FMPSPDIS
The function is based of different principles to identify the fault type. The signals from the
different fault identification algorithms are combined in selection logic.
The advanced parameters for faulty phase identification are chosen to the default setting
values.
1. Set IMaxLoad to 90 % of IBase 1000 A
The maximum load current for identification of three phase fault is calculated as:
×
1 2 180 .
³
IMaxLoad
×
3 138
GUID-0BF144D9-D5AC-490D-9CF5-2C67C4352ADA V1 EN
2. Set RLd to 70 Ω
The minimum apparent resistance during non-faulted conditions is calculated as:
2
V
min
£ × =
RLd 0 8 .
P
ext ,max
GUID-AA7CA356-FAA7-4504-8BA0-C8ADDFC40C68-ANSI V1 EN
3. Set LdAngle to 30º
It is normally considered that the apparent impedance during non-faulted condition
has a phase angle in the range ± 30º.
Calculating settings for scheme communication logic with delta
based blocking scheme signal transmit ZCPSCH (85)
The communication logic is used to assure fast fault clearance for all faults along the line,
that is also for faults outside the zone 1 reach of the distance protection. The logic for the
communication schemes requires a communication link between the distance protection
on the two line ends. The communication link alternatives are:
• Power line carrier (PLC)
• Microwave link (radio)
• Optic fibre link
The following alternatives for communication scheme are possible:
=
0 90 . kA
( ) 2
×
0 9 138 .
= W
85 7 .
180
Section 3
REL650 setting examples
(Equation 19)
(Equation 20)
57