Identification of key transmission lines in power grid using modified K-core decomposition

Power grid today has been more interconnected than it used to be, resulting in frequent occurrence of cascading failure in the power system. According to historical data, many major cascading failures are caused by the outage of certain transmission lines. The transmission lines with potential to cause large scale cascading failure are called key transmission lines (KTL). To find out the KTL, this paper first proposes a correlation network which characterized the interaction between different lines in the system. Then, based on this new network, we identify the KTL in power system using the modified K-core decomposition, which has been amended to better suit the power system´s inherit features. Finally, case studies utilizing cascading failure simulation on New England System and IEEE-118 system are conducted to substantiate the effectiveness and efficiency of the proposed approach.