Abstract: When a generator breaks down in the power grid, the fault generator can not provide power for the power grid, which may lead to cascading overload of other generators and affect the normal operation of the entire power grid. In this paper, the class Kuramoto model is applied to propose a stratege of power recovery by removing load nodes according to the degree of vulnerability, when a generator breaks down in the power grid. The study also compares the effects of removing the nodes with large degree of vulnerability and removing the nodes with small degree of vulnerability on the network performance. It is shown that when a node with small degree of vulnerability is removed, the critical coupling strength K_c of the remaining subsystems is smaller, the maximum absolute value of node frequency offset |Δw|_max is smaller and the minimum load disturbance intensity ΔP_min of the remaining system is larger than those, when a node with large degree of vulnerability is removed. Therefore, when a generator breaks down in the power grid, in order to make the power grid restore to steady-state, using this method can effectively eliminate the fault.

Key words: class Kuramoto model, degree of vulnerability, network performance, critical coupling strength, minimum load disturbance intensity