Design - ABB Relion Technical Manual

Section 10
Frequency protection
10.3.6.3
BLOCK
freqNotValid
Rate-of-Change
of Frequency
Frequency
ANSI08000009 V1 EN
Figure 155: Schematic design of Rate-of-change frequency protection SAPFRC (81)
10.3.7
330

Design

Comparator
If
[PUFreqGrad<0
PICKUP
AND
df/dt < PUFreqGrad]
OR
[PUFreqGrad>0
AND
df/dt > PUFreqGrad]
Then
PICKUP
Comparator
f > RestoreFreq
Technical data
Table 197: SAPFRC (81) technical data
Function
Operate value, pickup function
Operate value, restore enable
frequency
Timers
Operate time, pickup function
BLOCK
OR
Definite Time Delay
tTrip
tRestore
Range or value
(-10.00-10.00) Hz/s
(45.00 - 65.00) Hz
(0.000 - 60.000) s
At 50 Hz: 100 ms typically
At 60 Hz: 80 ms typically
1MRK 502 048-UUS A
BLKDMAGN
Pickup
&
Trip
Output
Logic
100 ms
RESTORE
ANSI08000009_en_1.vsd
Accuracy
± 10.0 mHz/s
± 2.0 mHz
<130 ms
-
Technical manual
PICKUP
TRIP