Siemens 7SJ85 - Undervoltage-Controlled Reactive-Power Protection; Overview of Functions; Structure of the Function

Undervoltage-Controlled Reactive-Power Protection
Overview of Functions
The Undervoltage-controlled reactive-power protection function (ANSI 27/Q):
•
Detects critical power-system situations, mainly in case of regenerative generation
•
Prevents a voltage collapse in power system by disconnecting the power-generation facility from the
main power systems
•
Ensures reconnection under stable power-system conditions
Structure of the Function
The Undervoltage-controlled reactive-power protection function can be used in protection function groups
containing 3-phase voltage and current measurement. Depending on the device, it is preconfigured by the
manufacturer with 1 Protection stage and 1 Reclosure stage. A maximum of 2 Protection stages and 1
Reclosure stage can operate simultaneously within the function.
[dwqvprot-110713-01.tif, 1, en_US]
Figure 6-244 Structure/Embedding of the Function
6.40
6.40.1
6.40.2
Protection and Automation Functions
6.40 Undervoltage-Controlled Reactive-Power Protection
SIPROTEC 5, Overcurrent Protection, Manual 827
C53000-G5040-C017-8, Edition 07.2017