This talk is partially based on the IEEE Proc.  paper, Nov 2005
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Typical sequence of events during  a blackout
•A piece of equipment  disconnects in one control area (CA);
•This causes  violations of limits on other pieces of equipment (in the affected and/or other CAs);
•Protection disconnects the affected equipment
•This further creates  power imbalances/overflows/frequency deviations/insufficient voltage support (in the CA where the initial event occurred and/or throughout the interconnection);
•These are seen in slow  inter-area oscillations and, ultimately  loss of synchronism
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