ABB REC670 Applications Manual page 202

Section 8
Current protection
196
= × +
V 3I (Z 3R )
0 A 0 T ,0 N
EQUATION2024-ANSI V1 EN-US
= × +
V 3I (Z 3R
OB 0 T ,0 N
EQUATION2025-ANSI V1 EN-US
The residual power, measured by the sensitive ground fault protections in A and B will
be:
= ×
S 3V 3I
0A 0A 0
EQUATION2026-ANSI V1 EN-US
= ×
S 3V 3I
0B 0B 0
EQUATION2027-ANSI V1 EN-US
The residual power is a complex quantity. The protection will have a maximum
sensitivity in the characteristic angle RCA. The apparent residual power component in
the characteristic angle, measured by the protection, can be written:
= × ×
S 3V 3I cos
0 A ,prot 0 A 0
EQUATION2028-ANSI V1 EN-US
= × ×
S 3V 3I cos
0 B,prot 0 B 0
EQUATION2029-ANSI V1 EN-US
The angles φ and φ are the phase angles between the residual current and the
A B
residual voltage in the station compensated with the characteristic angle RCA.
The protection will use the power components in the characteristic angle direction for
measurement, and as base for the inverse time delay.
The inverse time delay is defined as:
× × ×
TDSN (3I 3V cos (reference))
=
t 0 0
inv f
×
3I 3V cos (measured)
0 0
EQUATION2069 V1 EN-US
The function can be set Enabled/Disabled with the setting of Operation.
+
Z )
lineAB,0
j
A
j
B
f
1MRK 511 401-UUS A
(Equation 52)
(Equation 53)
(Equation 54)
(Equation 55)
(Equation 56)
(Equation 57)
(Equation 58)
Bay control REC670 2.2 ANSI
Application manual