ABB Relion RES670, Applications Manual

Page: 120 / 382

min
1 30 tP ms
=
EQUATION1348 V1 EN-US
(Equation 24)
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 25)
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 26)
max1
75.8
0.61
123.5
= = =
RLdInFw
kLdRFw
RLdOutFw
EQUATION1351 V1 EN-US
(Equation 27)
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 .
max
91.5 64.5
2 10.7
360 7 360
In Out
sc
tP ms
f
d d
- ° - °
= = =
× ° × °
EQUATION1352 V1 EN-US
(Equation 28)
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 .
Section 7
1MRK 511 407-UEN C
Impedance protection
114 Phasor measurement unit RES670 2.2 IEC
Application manual