This article holds an initial look into grid frequency on 13th February 2024. It may be expanded upon in the future.
The “significant power system event” event was noted in 4 Loy Yang A units simultaneously trip, on Tuesday 13th February 2024, and subsequently in Mainland System Frequency drops through the floor with “Significant Power System Event” on Tue 13th Feb 2024
The following chart of grid frequency recorded on the 13th of February 2024 captures the event, before and after.
Grid frequency dropped to 49.689 Hz. According to our logger this occurred between 13:09:56 and 13:09:57 (NEM time, UTC+10)
Relative to the normal frequency operating band, the excursion below 49.85 Hz lasted about
18 minutes 8 minutes (corrected).
Zooming into the start of the event we see the dip in frequency just before 13:08:48. There was a corresponding correction (was this 1Sec FCAS?) that pushed the frequency above 50 Hz before it slipped again down and outside the lower normal operating band, to the low point of 49.689 Hz at 13:09:56.