As near as I can make out, this is what we think occurred:
- A utility worker near Yuma, AZ was replacing a capacitor, and there was a malfunction of some sort
- In response to resulting conditions on the line, a major transmission link between the Colorado River power systems along the AZ/CA border and the San Diego area detected irregularities, and was shut down
- Some sort of secondary problem developed, which caused the gigantic San Onofre nuclear plant to experience a power cut (Yes, the power plant lost power! Huh!)
- Available power existed, but could not be delivered, from Arizona, to California, due to the transmission link being down.
- San Onofre operators decided that the safe thing to do was to initiate a system shutdown. This deprived, oh, 5 million people of electricity.
- Some sort of higher-level desparation cut-off stopped the cascading shutdown before it hit L.A. Or 20 million more people would have been affected.
- The lines were checked, the system was reset, San Onofre went through its (multi-hour?) re-boot
- 18 hours later, "the system" was back online.
I spend a lot of my time studying and thinking about failures. From what I can tell, there is a lot to study and learn about here.
Any good pointers to send me? Drop me a line, and let me know!