Leonhard Gandhi’s Post

Was Frieburg, DE also affected?

Hi Leonhard Thank you very much for sharing your analysis/data. I'm curious how you calculated K, or if you found it published somewhere. I couldn’t find it, but I reached the same value as you by using approximated data from the total European TSO K value (coming from ENTSO-E) and applying the percentage for Spain. FYI ~50 Mhz (1st loss of generation), and ~100 MHz (2nd loss of generation) would align with a statement made by a representative of the Spanish photovoltaic industry regarding generation power loss. Just in case it might be interesting, this is my analysis from a couple of days ago, that contains references and data https://www.linkedin.com/pulse/technical-yet-accessible-guide-spains-blackout-week-1-santamarta-eaadf

Great additional analysis and insights thank you! Two questions: 1.) Do you have a good view on what this ~0.6 HZ from 1 could be? We've seen the 0.2 HZ before in Europe so that's not new. 2.) How did you calculate the estimate of 650 MW for the initial gen loss for 3? If this is accurate and it was definitely a single plant, that would imply that the first gen loss was a CCGT, and not PV as many have been claiming.

Hi Leonhard Probst , thanks for the nice summary. Why the phase angle difference is once 0° and once roughly 30° at 12:33:16 ?

Do I understand you correctly: the 650MW loss is a calculated value, Not one taken from - potentially erroneous- REE data?

Thanks for the analysis. For me most interesting data presented is the plot of relative phase angle vs time on page 3. It is an interestingly smooth curve. Is this based on the difference between two PMU phase measurements (if so at what sample rate) or has it been derived by other means?

Leonhard Probst thanks for sharing. Two questions from my side: -Looks like Spain doesn't recover at all from the frequency drop in the first loss at 12:32:57?? -Looks like Portugal RoCoF is higher after the loss of the FR-ES interconection meaning higher loss of generation before Spain??

Excellent new input. Thanks! Clearly damping of oscillation during 2nd event have been more efficient. i.e. PSSs at the rotating generators "know" and react better to 0.21Hz. The 1st event is different, and contains something new, perhaps very local or the Iberia system composition at that moment. We will definitely understand more when we see some records of the active power flows and voltage profile.

The map below shows a time-frequency analysis of the grid frequency in Freiburg (D), based on the 100 ms sampled data, kindly made available in the post. A 10-minute slice of a filtered signal was analyzed, centered on the main event. The colors on the map represent the absolute intensity of the frequency oscillations. The blue contours overlaid on the map highlight the local dominance. A rising trace appears during the 3 minutes preceding the blackout, which could suggest the onset of a frequency drift somewhere (but it could also be an artifact of the DIY tool used for this analysis). In any case, it could be interesting to repeat the same analysis on a frequency signal captured in the Iberian Peninsula. Any suggestions on how to get this data?