ABB RES670 Applications Manual page 120

Section 7
Impedance protection
114
=
tP 1 30 ms
min
EQUATION1348 V1 EN-US
d
= ° × ×
360 f tP
-
In min si
EQUATION1349 V1 EN-US
=
RLdInFw
max1
×
2 tan
EQUATION1350 V1 EN-US
RLdInFw
=
kLdRFw
RLdOutFw
EQUATION1351 V1 EN-US
Also check if this minimum setting satisfies the required speed for detection of
consecutive oscillations. This requirement will be satisfied if the proposed setting
of tP2 time remains higher than 10 ms, see equation 28.
d d
-
= =
tP 2 In Out
max
× °
f 360
sc
EQUATION1352 V1 EN-US
The final proposed settings are as follows:
RLdOutFw = 123.5Ω
kLdRFw = 0.61
tP1 = 30 ms
tP2 = 10 ms
Consider RLdInFw = 75.0Ω.
Do not forget to adjust the setting of load encroachment resistance
RLdFw in Phase selection with load encroachment (FDPSPDIS or
FRPSPDIS) to the value equal to or less than the calculated value
RLdInFw. It is at the same time necessary to adjust the load angle
in FDPSPDIS or FRPSPDIS to follow the condition presented in
equation 29.
d
+ = ° ×
1 360 2.5 0.030 64.5
min Out
Z
155.75
S
=
d
æ ö æ
91.5
×
-
in min 2 tan
ç ÷ ç
è 2 ø è 2
75.8
= =
max1 0.61
123.5
° - °
91.5 64.5
=
10.7
× °
7 360
1MRK 511 407-UEN C
× + ° =
91.5
= W
75.8
ö
÷
ø
ms
Phasor measurement unit RES670 2.2 IEC
Application manual
(Equation 24)
°
(Equation 25)
(Equation 26)
(Equation 27)
(Equation 28)