Instruction manual
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AQ G3x7 Generator protection IED
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The inputs are
•
the RMS value of the fundamental Fourier component of the negative sequence
component of the phase currents,
•
parameters,
•
status signals.
The outputs are
•
the binary output status signals.
The software modules applied in the negative sequence overcurrent protection function are:
Fourier calculations
These modules calculate the basic Fourier current components of the phase currents
Negative sequence
This module calculates the basic Fourier current components of the negative sequence
current, based on the Fourier components of the phase currents.
Characteristics
This module calculates the required time delay based on the Fourier components of the
negative sequence current.
Decision logic
The decision logic module combines the status signals to generate the trip command of
the function.
The following description explains the details of the individual components.