ABB Relion 670 series - Phase-To-Ground Fault in Reverse Direction

PHS Zm
X0 1.44 X0³ ×
EQUATION1310 V1 EN (Equation 273)
where:
X1
Zm
is the reactive reach for the zone to be covered by FRPSPDIS (21), and the constant
1.44 is a safety margin
X0
Zm
is the zero-sequence reactive reach for the zone to be covered by FRPSPDIS (21)
The reactive reach in reverse direction is automatically set to the same reach as for forward
direction. No additional setting is required.
Fault resistance reach
The resistive reach must cover RFPG for the overreaching zone to be covered, mostly
zone 2. Consider the longest overreaching zone if correct fault selection is important in the
application. Equation
274 and 275 gives the minimum recommended resistive reach.
A) 60 degrees
1.1 ZmRFFwPG RFPG³ ×
ANSIEQUATION2223 V1 EN (Equation 274)
B) 90 degrees
( )
1
2 1 0
3
Zm Zm ZmRFFwPG R PG R PG RFPG> × × + +
ANSIEQUATION2224 V1 EN (Equation 275)
The security margin has to be increased in the case where φloop<60° to avoid that
FRPSPDIS (21) characteristic cuts off some part of the zone measurement characteristic.
RFFwPP and RFFRvPP must be set in a way that the loop characteristic angle can be 60
degrees (or alternatively the same or lower compared to the measuring zone that must be
covered). If the characteristic angle for IEDs in the 500 series of 90 degrees is desired,
RFFwPP and RFFRvPP must be set to minimum setting values.
8.10.3.2 Phase-to-ground fault in reverse direction
Reactive reach
The reactive reach in reverse direction is the same as for forward so no additional setting
is required.
Section 8 1MRK 506 369-UUS -
Impedance protection
342 Line distance protection REL670 2.2 ANSI
Application manual