ABB RES670 Applications Manual page 170

Section 8
Current protection
164
Minimum recommended setting is 0.2% of S
the IED are used.
= × ×
S 3 UBase IBase
N
EQUATION1708 V1 EN-US
The setting Angle1(2) gives the characteristic angle giving maximum sensitivity of
the power protection function. The setting is given in degrees. For active power the
set angle should be 0° or 180°. 0° should be used for generator low forward active
power protection.
Operate
Angle1(2) = 0
Power1(2)
IEC06000556 V1 EN-US
Figure 67: For low forward power the set angle should be 0° in the
underpower function
TripDelay1(2) is set in seconds to give the time delay for trip of the stage after pick
up.
Hysteresis1(2) is given in p.u. of generator rated power according to equation 66.
= × ×
S 3 UBase IBase
N
EQUATION1708 V1 EN-US
The drop out power will be Power1(2) + Hysteresis1(2).
The possibility to have low pass filtering of the measured power can be made as
shown in the formula:
when metering class CT inputs into
N
Q
°
en06000556.vsd
Phasor measurement unit RES670 2.2 IEC
1MRK 511 407-UEN C
(Equation 65)
P
(Equation 66)
Application manual