Grid-adaptive equivalencing of power system for generator tripping

This paper presents a practical yet accurate equivalencing method of power system for an online transient stability assessment. The proposed vector composition method effectively aggregates the multiple generators and transmission lines of the power system, and develops a grid-adaptive equivalent for which well-established analysis technique can be applied to assess the power system stability. It thus allows for activating preventive or corrective measures on time to stabilize the system in emergency. The parameters of the equivalent can be refined using the synchronized measurement data, and the transient stability margin can be updated. The efficacy and accuracy are validated for a multi-machine infinite bus system, and the utility planning model of Korea electric power system where an equal area criterion and the generator tripping are employed for assessing the stability and stabilizing action as specified in the special protection schemes for the Korea electric power system.