Research on the Screening of Multiple Contingency and Its Failure Probability Assessment Technology in Natural Disasters

It has become a common consensus that the blackout defense framework has been extended to the early warning of natural disasters. The generation of multiple contingencies and their probability assessment in natural disasters are the basis of risk assessment and preventive control of power system. Firstly, the generation method of multiple contingencies which takes into account the disaster simultaneity and spatial correlation is discussed. And the failure probability assessment method based on the coupling relationship between the transmission lines is proposed. Secondly, according to the characteristics of narrow transmission channels which is concerned by dispatcher, a failure probability correction method for narrow transmission channels is proposed by classifying related towers of transmission channels. Then, based on the designed severity prediction coefficient index, a method of screening multiple contingencies is proposed. Finally, an example of a provincial power grid is given to illustrate the effectiveness of the proposed method .