The practical strategy to prevent cascading trips based on the related branches with hidden danger

Concerning the actual status of protection in the power grid, a new strategy is proposed in this paper to prevent the chain tripping accident. Logical judgment is reasonably arranged in this strategy, some logic judgments are set before reclosing, in order to make full use of the reclosing time, and put the rest of the logical judgment between the start of the back-up protection and reclosing. On the condition that the traditional relay protection can react accurately and quickly, block the distance backup protection which may misoperate to prevent the cascading trips caused by power flow transferring.