Areva MiCOM P441, Техническое руководство

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Application Notes P44x/EN AP/E33
MiCOM P441/P442 & P444 Page 13/220
All phase fault protection elements are quadrilateral shaped, and are directionalied as
follows:
•
Zones 1, 2 and 3 - Directional forward zones, as used in conventional three zone
distance schemes. Note that Zone 1 can be extended to Zone 1X when required in
zone 1 extension schemes (see page 17 §2.5.2).
•
Zone P - Programmable. Selectable in MiCOM S1 (Distance scheme\Fault type) as
a directional forward or reverse zone.
•
Zone 4 - Directional reverse zone. Note that zone 3 and zone 4 can be set with
same Rloop value to provide a general start of the relay.
Remark: If any zone i presents a Rloop i bigger than R3=R4, the limit of the
start is always given by R3. See also the "Commissioning Test"
chapter.
2.3 Earth fault distance protection
The P441, P442 and P444 relays have 5 zones of earth (ground) fault protection, as shown
in the earth loop impedance plot Figure 2 below.
Type of fault can be selected in MiCOM S1 (only Phase/Phase or P/P & P/Ground)
R4G
=
P0471ENa
R3G RpG R2G R1G
ZONE 3
ZONE 1
ZONE P Reverse
ZONE 4
ZONE 1X
ZONE 2
ZONE P (Programmable)
X ( /phase)
R ( /phase)
1+KZ
1
1+KZ
2
1+KZ
p
1+KZ
3/4
1+KZ
3/4
FIGURE 2 – PHASE/GROUND FAULT QUADRILATERAL CHARACTERISTICS ( /PHASE SCHEME)
Remarks: 1. In a
Ω
/phase scheme the R value must be divided by 1+K
Z
(for
phase/ground diagram)
2. The angle of the start element (Quad) is the angle of the
2Z
1
+Z
0
(Z
1
: positive sequence Z, Z
0
: zero sequence Z)
3. See calculation of K
Z
in section 2.6.5.