Operate
Angle1(2) = 0
°
Power1(2)
P
Q
en06000556.vsd
IEC06000556 V1 EN
Figure 122: 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.
The possibility to have low pass filtering of the measured power can be made as shown in
the formula:
S TD S TD S
Old Calculated
= ⋅ + −
( )
⋅1
EQUATION1893-ANSI V1 EN
(Equation 163)
Where
S is a new measured value to be used for the protection function
S
old
is the measured value given from the function in previous execution cycle
S
Calculated
is the new calculated value in the present execution cycle
TD
is settable parameter
The value of TD=0.98 or even TD=0.99 is recommended in generator low forward power
applications as the trip delay is normally quite long. This filtering will improve accuracy
of the power function.
1MRK 506 334-UUS A Section 7
Current protection
251
Application manual
To Next Page
Loading...
