Captured Power System Transient: 3.2

• Would you like to think over what might have happened?
• where it might have happened (e.g. at upstream or downstream of the feeder)?
• how serious or critical it might have been, how the seriousness can be decided?
• why it might have happened, if there may be any prevention measure?

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The last #VoltageTransient event group is about #Notching. Over the 6-7 months observation period:

• #Notches frequently but not regularly occurred;
• #Notches were mainly on 2.phase, but sometimes spread to other phases;
• #Notches occasionally followed by oscillatory transients or #VoltageNotchingRinging (IEEE 1159-2019).

#Notches occurred in two different days are selected to be presented as parts of #Notching event group.

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The second and last capture set of #Notch events are associated with 4th of February 2009.

There are 5 captures of #Notches at 2 different times of the day, one in the morning and 4 in the noon. #Notch in the morning occurred only at 2.Phase. #Notches in the noon started with occurring at 2.Phase as #VoltageNotchingRinging (IEEE 1159-2019) and then spread to other Phases.

Capture-1:

• Captured on 4th of February 2009 at 09:52:33.869
• Resolution Frequency of Recording: 25617 Hz
• Recording started 30 ms prior from event moment

Capture-2:

• Captured on 4th of February 2009 at 12:22:00.086
• Resolution Frequency of Recording: 25579 Hz
• Recording started 30 ms prior from event moment

Capture-3:

• Captured on 4th of February 2009 at 12:22:01.516
• Resolution Frequency of Recording: 25579 Hz
• Recording started 30 ms prior from event moment

Capture-4:

• Captured on 4th of February 2009 at 12:22:03.216
• Resolution Frequency of Recording: 25576 Hz
• Recording started 30 ms prior from event moment

Capture-5:

• Captured on 4th of February 2009 at 12:22:04.176
• Resolution Frequency of Recording: 25574 Hz
• Recording started 30 ms prior from event moment