Resistive Reach In Forward Direction - ABB RES670 Technical Manual

1MRK 511 408-UUS A
7.1.6.1
Phasor measurement unit RES670 2.2 ANSI
Technical manual
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EQUATION1557 V1 EN-US
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EQUATION1558 V1 EN-US
The R and X are R and X boundaries.
set set

Resistive reach in forward direction

To avoid load encroachment, the resistive reach is limited in forward direction by
setting the parameter RLdOutFw which is the outer resistive load boundary value while
the inner resistive boundary is calculated according to equation 5.
RLdInFw = kLdRFw·RLdOutFw
EQUATION1185 V2 EN-US
where:
kLdRFw is a settable multiplication factor less than 1
The slope of the load encroachment inner and outer boundary is defined by setting the
parameter LdAngle.
The load encroachment in the fourth quadrant uses the same settings as in the first
quadrant (same LdAngle and RLdOutFw and calculated value RLdInFw).
The quadrilateral characteristic in the first quadrant is tilted to get a better adaptation to
the distance measuring zones. The angle is the same as the line angle and derived from
the setting of the reactive reach inner boundary X1InFw and the line resistance for the
inner boundary R1LIn. The fault resistance coverage for the inner boundary is set by
the parameter R1FInFw.
From the setting parameter RLdOutFw and the calculated value RLdInFw a distance
between the inner and outer boundary, DFw, is calculated. This value is valid for R
direction in first and fourth quadrant and for X direction in first and second quadrant.
Section 7
Impedance protection
(Equation 3)
(Equation 4)
(Equation 5)
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