ABB RELION REX640, Техническое руководство, Страница: 1835 / 1960

Voltage swell set 3
Voltage swell set 2
Voltage swell set 1
Voltage
xUref
Time (ms)
0
0
VVa Dur Max VVa swell time 3 VVa swell time 1 VVa swell time 2
1.40
Instantaneous
swell
Temporary
swell
Momentary
swell Maximum duration
swell
1.00
Figure 971: Voltage swell operational regions
For interruption, as shown in
Figure 972
, there is only one magnitude limit but
four duration limits for interruption classification. Now the event and counter type
depends only on variation duration time.
Voltage Int set
Voltage
xUref
Time (ms)
0
0
VVa Dur Max VVa Int time 3 VVa Int time 1 VVa Int time 2
1.00
Momentary
interruption
Sustained
interruption
Temporary
interruption
Maximum duration
interruption
Figure 972: Interruption operating regions
Generally, no event detection is done if both the magnitude and duration
requirements are not fulfilled. For example, the dip event does not indicate if the
TRMS voltage magnitude remains between
Voltage dip set 3 and Voltage dip set 2
for a period shorter than
VVa dip time 3 before rising back above Voltage dip set 3.
The event indication ends and possible detection is done when the TRMS voltage
returns above (for dip and interruption) or below (for swell) the activation-starting
limit. For example, after an instantaneous dip, the event indication when the voltage
magnitude exceeds
Voltage dip set 1 is not detected (and recorded) immediately
but only if no longer dip indication for the same dip variation takes place and
maximum duration time for dip variation does not exceed before the signal
magnitude rises above
Voltage dip set 3. There is a small hysteresis for all these
limits to avoid the oscillation of the output activation. No drop-off approach is
applied here due to the hysteresis.
Consequently, only one event detection and recording of the same variation type
can take place for one voltage variation, so the longest indicated variation of each
variation type is detected. Furthermore, it is possible that another instantaneous
dip event replaces the one already indicated if the magnitude again undershoots
Voltage dip set 1 for the set time after the first detection and the signal magnitude
1MRS759142 F Power quality measurement functions
REX640
Technical Manual
1835