A Complex Network Theory and Conditional Probability Based Risk Assessment Method for Disastrous Accidents

Applying complex network theory and risk theory and synthetically considering operation conditions of power grid and its topological structure, a method based on conditional probability risk indicators of Bayesian network to assess disastrous accident occurred in power grid is proposed. The concept of electrical betweenness is led in the proposed method to resolve the deficiency in traditional risk assessment that in the severity of fault only operational conditions of power grid are considered and topological structure of power grid is not considered. Applying conditional probability the defect in traditional risk assessment that the fault probabilities of elements are independent one another can be remedied. A risk index system of disastrous accidents is established to characterize operational risk under current status of power grid and depict the developing trend from cascading failure to disastrous accident. Simulation results show that the proposed method can effectively identify the risks existing in power grid, thus reference information that is available for power grid security assessment can be offered.