1MRK 511 358-UUS A
Section 11
11.1
Multipurpose filter SMAIHPAC
11.1.1
Identification
Function description
Multipurpose filter
11.1.2
Application
The multi-purpose filter, function block with name SMAI HPAC, is arranged as a three-phase filter.
It has very much the same user interface (e.g. function block outputs) as the standard pre-
processing function block SMAI. However the main difference is that it can be used to extract any
frequency component from the input signal. For all four analogue input signals into this filter (i.e.
three phases and the residual quantity) the input samples from the TRM module, which are coming
at rate of 20 samples per fundamental system cycle, are first stored. When enough samples are
available in the internal memory, the phasor values at set frequency defined by the setting
parameter
calculated phasors:
•
Magnitude
•
Phase angle
•
Exact frequency of the extracted signal
The SMAI HPAC filter is always used in conjunction with some other protection function (e.g. multi-
purpose protection function or overcurrent function or over-voltage function or over-power
function). In this way many different protection applications can be arranged. For example the
following protection, monitoring or measurement features can be realized:
•
Sub-synchronous resonance protection for turbo generators
•
Sub-synchronous protection for wind turbines/wind farms
•
Detection of sub-synchronous oscillation between HVDC links and synchronous generators
•
Super-synchronous protection
•
Detection of presence of the geo-magnetic induced currents
•
Overcurrent or overvoltage protection at specific frequency harmonic, sub-harmonic, inter-
harmonic etc.
•
Presence of special railway frequencies (e.g. 16.7Hz or 25Hz) in the three-phase power system
•
Sensitive reverse power protection
•
Stator or rotor earth fault protection for special injection frequencies (e.g. 25Hz)
•
etc.
The filter output can also be connected to the measurement function blocks such as CVMMXN
(Measurements), CMMXU (Phase current measurement), VMMXU (Phase-phase voltage
Application manual
System protection and control
IEC 61850
identification
SetFrequency are calculated. The following values are internally available for each of the
IEC 60617
identification
SMAIHPAC
-
System protection and control
GUID-6B541154-D56B-452F-B143-4C2A1B2D3A1F v1
GUID-8224B870-3DAA-44BF-B790-6600F2AD7C5D v1
ANSI/IEEE C37.2
device number
-
GUID-A1F20DD8-571E-42C3-84F3-C557EC352ED0 v1
Section 11
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