The algorithm of power system security detection comprehensive decision based on Dempster-Shafer theory improved combination rule

To evaluate whether the construction of power secondary system classified protection reaches the standard, we take Dempster-Shafer theory to combine the security detection results. In the process of studying rule of combination, it is found that the original rule isn't very effective in handling the evidence with high degree of conflict. There have been several improvement methods but their effects aren't very ideal. Therefore, this paper proposes the concept of average of conflict's volatility between evidence. We design a novel combination rule of Dempster-Shafer theory based on it and establish a modified algorithm of comprehensive decision. This algorithm can solve the problem of the high degree conflict between evidence and reduce the affection of uncertainty factors more effectively than others so that it can obtain a better compliance decision result and protect the running of power primary and secondary system.