ABB RED650, Applications Manual

Page: 147 / 454

min
1 30 tP ms
=
EQUATION1348 V1 EN-US
(Equation 87)
min min
360 1 360 2.5 0.030 64.5 91.5
In si Out
f tP
d d
-
= °× × + = °× × + ° = °
EQUATION1349 V1 EN-US
(Equation 88)
max1
min
155.75
75.8
91.5
2 tan 2 tan
2 2
d
-
= = = W
æ ö æ ö
×
×
ç ÷ ç ÷
è ø
è ø
S
in
Z
RLdInFw
EQUATION1350 V1 EN-US
(Equation 89)
max1
75.8
0.61
123.5
= = =
RLdInFw
kLdRFw
RLdOutFw
EQUATION1351 V1 EN-US
(Equation 90)
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 91 .
max
91.5 64.5
2 10.7
360 7 360
In Out
sc
tP ms
f
d d
- ° - °
= = =
× ° × °
EQUATION1352 V1 EN-US
(Equation 91)
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
92 .
1MRK 505 393-UEN B
Section 7
Impedance protection
Line differential protection RED650 2.2 IEC 141
Application manual