Load-shedding in distribution systems during wide area disturbances

The 2003 blackouts in North America and Europe showed the importance of load-shedding during wide area disturbances. The analysis of the events that ended with system collapse resulted in multiple recommendations from the international commissions. Some of them highlight the importance and need for improvements of underfrequency load-shedding and at the same time require the implementation of undervoltage load-shedding.