Fast prediction of cascading overload on transmission section based on DC sensitivity and compensation method

If the overload branch is tripped, the power flow will transfer to other branches in corresponding transmission section. Therefore, fast prediction of cascading overload is of great significance for transmission section security protection. This paper proposes an algorithm combined with DC sensitivity and compensation method after the traditional study of branch outage. Based on DC power flow model, branch active power transferring sensitivity is introduced to describe the impact of overload branch outage on other branches. The compensation method is applied with an equation of active power into nodes simulating the branch outage. Then the original sensitivity matrix can be effectively used regardless the change of network and complicated power calculation is avoided. RCTL (relative cluster of the transmission line) including the transmission section in which the overload branch lies and alert branches will be analyzed to predict whether there is cascading overload. And results will provide the basis for whether to take urgent control measures to eliminate the overload. The rapidity and validity of the algorithm is verified by calculation results of CEPRI 36 test system.