Functions
2.19 Reverse-Power Protection Application with Flexible Protection Function
[7sj80-anschl-rueckleist-schutz-20061205, 1, en_US]
Figure 2-104
Implementation of the Reverse Power Protection
2.19.2
General
The names of messages can be edited in DIGSI and adjusted accordingly for this example. The names of the
parameters are fixed.
Determination of the Reverse Power
The reverse power protection evaluates the active power from the symmetrical components of the funda-
mental harmonics of the voltages and currents. The evaluation of the positive sequence systems causes
reverse power determination to be independent of the asymmetries in currents and voltages and reflects the
real load of the driving end. The calculated active power value corresponds to the total active power. The
connection in the example illustrates positive measurement of power in the direction extending from the
busbar to the transformer of the device.
Functional Logic
The following logic diagram depicts the functional logic of the reverse power protection.
256
Wiring diagram for a 7SJ80 as reverse power protection
SIPROTEC 4, 7SJ80, Manual
E50417-G1140-C343-A8, Edition 12.2017