ABB Relion 670 Series Applications Manual page 194

Section 7
Current protection
=
S 3 VBase IBase
N
EQUATION2047 V1 EN-US
The setting
protection function. The setting is given in degrees. For active power the set angle should be 0° or
180°. 180° should be used for generator reverse power protection.
Operate
IEC06000557 V2 EN-US
Figure 88: For reverse power the set angle should be 180° in the overpower 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 88.
=
S 3 VBase IBase
N
EQUATION2047 V1 EN-US
The drop out power will be
The possibility to have low pass filtering of the measured power can be made as shown in the
formula:
188
× ×
Angle1(2) gives the characteristic angle giving maximum sensitivity of the power
Power 1(2)
× ×
Power1(2) - Hysteresis1(2) .
Q
o
Angle1(2 ) = 180
IEC06000557-2-en.vsd
1MRK 511 358-UUS A
(Equation 87)
P
(Equation 88)
Application manual