About the relationship of line overload cascading and loss of synchronism in electric power systems

This paper discusses the relationship of line overload cascading and loss of synchronism in interconnected power systems. The mechanisms of recent blackouts ending in loss of synchronism are reviewed and assessed. Further, theoretical considerations about the phenomenom of loss of synchronism ending in Out of Step (OOS) are discussed. Moreover, loss of synchronism scenarios are simulated in a multi-area power system simulation, where special emphasis is paid on accurate modeling of involved asset and system protection functions. Based on the assessment of these simulations, recommendations for the design of system protection schemes are given.