Abstract: Abstract:The “4·10” large area blackout accident of Shenzhen Power Grid at 2012 is the blackout accident in Guangdong province with largest load loss in recent years. The occurrence of the large area blackout accident and the treating process of dispatch department were introduced, and the main reasons of the large area blackout accident were summarized, which are combined failures of the equipments in the same substation within a short time and irrational bus connection in the hub substation. Considering dispatching, operation, power grid planning and power grid management, the measures and suggestions were proposed to avoid similar accident.

Key words: Keywords:large area blackout, hub substation, power grid partition, switching operation, power grid planning