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Instruction manual
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AQ G3x7 Generator protection IED
96 (211
)
Figure 3-57: Structure of directional underpower protection.
The inputs are
•
The RMS value of the fundamental Fourier component of the three phase currents
(IL1, IL2, IL3),
•
the RMS value of the fundamental Fourier component of the three phase voltages
(UL1, UL2, UL3),
•
Parameters
•
Status signals.
The function can be enabled or disabled (BLK input signal). The status signal of the VTS
(voltage transformer supervision) function can also disable the directional operation.
The outputs are
•
The binary output status signals.
Software modules of the function block are as follows:
P-Q Calculation
Based on the RMS values of the fundamental Fourier component of the three phase
currents and of the three phase voltages, this module calculates the three-phase active and
reactive power values.