PID-3390-OUTPUTSIGNALS v7
Table 417: SMAIHPAC Output signals
Name Type Description
AI3P GROUP SIGNAL Analog input 3-phase group
AI1 GROUP SIGNAL Analog input 1
AI2 GROUP SIGNAL Analog input 2
AI3 GROUP SIGNAL Analog input 3
AI4 GROUP SIGNAL Analog input 4
12.1.5 Settings
GUID-5EA398AD-66E2-4240-8918-4332995CED11 v1
PID-3390-SETTINGS v7
Table 418: SMAIHPAC Non group settings (basic)
Name Values (Range) Unit Step Default Description
ConnectionType Ph - Ph
Ph - N
- - Ph - N Analogue input connection type
SetFrequency 2.0 - 500.0 Hz 0.1 50.0 Desired frequency to be extracted by the
filter
FreqBandWidth 0.0 - 60.0 Hz 0.1 0.0 Extra added frequency band around the
set frequency
FilterLength 0.1 s
0.2 s
0.5 s
1.0 s
2.0 s
4.0 s
- - 1.0 s Approximate length of the filtering
window in seconds
OverLap 0 - 95 % 5 20 Filtering window overlap between two
calculations in percent
12.1.6 Operation principle
GUID-262C1783-3A0A-46B6-99FC-1202AE8E7519 v2
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
SetFrequency
are calculated. The
following values are internally available for each of the calculated phasors:
• Magnitude
• Phase angle
• Exact frequency of the extracted signal
Note that the special filtering algorithm is used to extract these phasors. This algorithm is
different from the standard one-cycle Digital Fourier Filter typically used by the numerical IEDs.
This filter provides extremely good accuracy of measurement and excellent noise rejection, but at
the same time it has much slower response time. It is capable to extract phasor (i.e. magnitude,
phase angle and actual frequency) of any signal (e.g. 37,2Hz) present in the waveforms of the
connected CTs and/or VTs. The magnitude and the phase angle of this phasor are calculated with
Section 12 1MRK 502 066-UUS B
System protection and control
722
Technical manual
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